Anti-Spin Differential on a Mall Crawler? - Page 5 - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > JK Jeep Wrangler Forum > JK General Discussion Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 06-21-2013, 01:45 PM   #121
yeah,,,, im that good

5-Year WF Supporting Member
 
panthermark's Avatar
 
Join Date: Aug 2011
Location: Chicago-land
Posts: 9,866
Images: 13
Quote:
Originally Posted by BubbaEinstein View Post
First of all realize you are asking this question in a forum full of off road junkies! But, understand this: a LSD is a poor choice for a city only Jeep because by design it sacrifices vehicle directional control for traction.

Example: Sitting at a light in rain wanting to turn right, light turns green, you turn right and get on the gas but it's oily/slippery!

LSD - good chance both rear tires will spin and you will fishtail and in a Jeep that can happen quickly - might end up doing a 360
Open - one tire spins and you just keep going whichever direction you have the wheel pointed...not very quickly, but you never lose directional control of the vehicle.

Key point is an open differential will only allow one tire on an axle to become "disconnected" from the pavement..a LSD will allow both and actually encourages it.

The videos posted of the "garbage" computer controlled differential BRD are irrelevant...this is for a city vehicle, not climbing sand dunes or snow mountains or boulders which do not exist in the middle of a parking lot.

To sum it up, an open differential will ALWAYS be safer when driving because it will never take away directional control from the driver. In certain circumstances you may get stuck but the situations where the open differential + traction control + BRD gets stuck where an LSD doesn't are extremely rare (can't really think of one personally but I'll assume they exist) but do not justify the inherent instability of an LSD for city driving.


You are talking about JK's.....so your scenarios (for both open diff and LSD) will never happen unless you gun the engine and have pulled the fuse for your ESP. Have you ever tried to do a donut in a snowy parking lot in a Jeep with ESP/traction control not disengaged?

You are not going to spin a tire in one spot, nor are you going to fishtail on do a 360. You are just going to sit there with you ESP light flashing and you brake pads burning up.

__________________
2013 Sahara Unlimited
Billet - Auto - 3.73 - Connectivity - Painted Hardtop - LSD - Remote Start - Saddle Leather - Side Airbags

I may mall crawl...but I look good doing it.....
panthermark is offline   Quote Quick Reply
Old 06-21-2013, 01:45 PM   #122
Rock-Rubber

WF Supporting Member
 
GoldenSahara00's Avatar
 
Join Date: Aug 2010
Location: SCPA
Posts: 16,728
Quote:
Originally Posted by BubbaEinstein View Post
First of all realize you are asking this question in a forum full of off road junkies! But, understand this: a LSD is a poor choice for a city only Jeep because by design it sacrifices vehicle directional control for traction.

Example: Sitting at a light in rain wanting to turn right, light turns green, you turn right and get on the gas but it's oily/slippery!

LSD - good chance both rear tires will spin and you will fishtail and in a Jeep that can happen quickly - might end up doing a 360
Open - one tire spins and you just keep going whichever direction you have the wheel pointed...not very quickly, but you never lose directional control of the vehicle.

Key point is an open differential will only allow one tire on an axle to become "disconnected" from the pavement..a LSD will allow both and actually encourages it.

The videos posted of the "garbage" computer controlled differential BRD are irrelevant...this is for a city vehicle, not climbing sand dunes or snow mountains or boulders which do not exist in the middle of a parking lot.

To sum it up, an open differential will ALWAYS be safer when driving because it will never take away directional control from the driver. In certain circumstances you may get stuck but the situations where the open differential + traction control + BRD gets stuck where an LSD doesn't are extremely rare (can't really think of one personally but I'll assume they exist) but do not justify the inherent instability of an LSD for city driving.

The only reason you would fish tail or lose directional control would be if you don't know how to drive and have a lead foot around turns. 99% of the time with a proper level of throttle, an LSD will allow you to keep traction where in another circumstance you may have spun one tire. Imagine pulling out in a blind spot on icy roads. Light throttle with the LSD lets you pull out with better traction, while any amount of throttle leaves your tires spinning, leaving you broadside across the road waiting to get hit.

Sure, if you're an idiot and can't drive than an LSD is dangerous. Just operating a vehicle is dangerous. We all learn to drive, and learning proper technique with an LSD isn't hard.

How do you think guys with auto or spooled locked rear diffs drive around on the road? light throttle through the turns, and they keep control. Not to mention the LSD on these jeeps is not that strong and isn't going to do as much "encouraging" of the rear wheels to break loose.

__________________
Ryan - A good eye, a light foot, and a smart rig.
Bolt-ons are boring
AMERICAN JEEPER
My Build - http://www.wranglerforum.com/f118/pr...a00-74622.html
Rausch Creek Trip: 2014 Trip Coming Soon
GoldenSahara00 is offline   Quote Quick Reply
Old 06-21-2013, 01:55 PM   #123
Jeeper
 
Join Date: Nov 2010
Posts: 771
This is going to require some deeper investigation, because something else is as play then. No way no how have I been driving in the snow in 2wd and even 4wd without some assistance. As mentioned the traction control only came on once, intentionally and agreed it feels like utter sh!t. Engine slowed down, jerky abs came on, loud and noisy. None of this while driving normally (not even reduced speed) for the record snow conditions in both 2 and 4. If there hasn't been some active electronic control going on I'd be utterly shocked. You can kiss your LSD goodbye if that is the case.

Let me check.
positrak is offline   Quote Quick Reply
Old 06-21-2013, 02:14 PM   #124
Jeeper
 
DC Dennis's Avatar
 
Join Date: Jul 2012
Posts: 379
Quote:
Originally Posted by positrak View Post
Seems to be mass confusion going on here, BLD vs Traction Control. MTH you mean traction control? Not BLD.

BLD is the "cheap" electronic LSD funcitioning in miliseconds. Traction control you got to be pretty agressive to invoke it and yes there is delay before/after.
BLD is a FUNCTION of the Traction Control, it is additional programing.
DC Dennis is offline   Quote Quick Reply
Old 06-21-2013, 02:21 PM   #125
yeah,,,, im that good

5-Year WF Supporting Member
 
panthermark's Avatar
 
Join Date: Aug 2011
Location: Chicago-land
Posts: 9,866
Images: 13
Quote:
Originally Posted by positrak View Post
This is going to require some deeper investigation, because something else is as play then. No way no how have I been driving in the snow in 2wd and even 4wd without some assistance. As mentioned the traction control only came on once, intentionally and agreed it feels like utter sh!t. Engine slowed down, jerky abs came on, loud and noisy. None of this while driving normally (not even reduced speed) for the record snow conditions in both 2 and 4. If there hasn't been some active electronic control going on I'd be utterly shocked. You can kiss your LSD goodbye if that is the case.

Let me check.
You might be thinking of ESC.
From what I understand, Traction Control will apply your brakes. ESC will apply your brakes and reduce your engine power. Traction Control and ESC are linked together, so it is hard to tell when one stops and the other starts.

ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake System
(ABS), Traction Control System (TCS), Brake Assist
System (BAS), Hill Start Assist (HSA), Electronic Roll
Mitigation (ERM), Electronic Stability Control (ESC),
Trailer Sway Control (TSC), and Hill Descent Control
(HDC). All of these systems work together to enhance
vehicle stability and control in various driving conditions,
and are commonly referred to as ESC.


Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. The ESC
corrects for over/under steering of the vehicle by applying
the brake of the appropriate wheel to assist in
counteracting the over/under steer condition. Engine
power may also be reduced to help the vehicle maintain
the desired path.
ESC uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match
the intended path, ESC applies the brake of the appropriate
wheel to assist in counteracting the oversteer or
understeer condition.
Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.

Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The “ESC Activation/Malfunction Indicator Light” (located
in the instrument cluster), starts to flash as soon as
the tires lose traction and the ESC system becomes active.
The “ESC Activation/Malfunction Indicator Light” also
flashes when TCS is active. If the “ESC Activation/
Malfunction Indicator Light” begins to flash during acceleration,
ease up on the accelerator and apply as little
throttle as possible. Be sure to adapt your speed and

driving to the prevailing road conditions.
The ESC system has three available operating modes in
4H range. The system has one operating mode in 4L
range. Two-wheel drive vehicles and four-wheel drive
vehicles in 2H range have two operating modes.
4H Range (4WD Models)
On
This is the normal operating mode for ESC in 4H range.
Partial Off
This mode is entered by momentarily pressing the ESC
OFF switch.
ESC Off
This mode is entered by pressing and holding momentarily
pressing the ESC OFF switch for 5 seconds.
When in
Partial Off mode, the TCS portion of ESC has
been disabled and the “ESC Activation/Malfunction

Indicator Light” will be illuminated.
All other stability features of ESC function normally. This
mode is intended to be used if the vehicle is in deep
snow, sand, or gravel conditions and more wheel spin
than ESC would normally allow is required to gain
traction. To turn ESC on again, momentarily press the
ESC OFF switch. This will restore the normal “ESC On”
mode of operation.
NOTE:
To improve the vehicle’s traction when driving
with snow chains, or starting off in deep snow, sand, or
gravel, it may be desirable to switch to the “Partial Off”
mode by pressing the ESC OFF switch. Once the situation
requiring ESC to be switched to the “Partial Off” mode is
overcome, turn ESC back on by momentarily pressing the
ESC OFF switch. This may be done while the vehicle is in
motion.
When in ESC Off mode, ESC and TCS, except for the
“limited slip” feature described in the TCS section, are

turned off. To turn ESC on again, momentarily press the
ESC OFF switch. This will restore normal “ESC On”
mode of operation.
2H Range (4WD Models) Or 2WD Models
On
This is the normal operating mode for ESC in 2H range
and on 2WD vehicles.
Partial Off
When in “Partial Off” mode, the TCS portion of ESC has
been disabled and the “ESC Activation/Malfunction
Indicator Light” will be illuminated.
All other stability features of ESC function normally. This
mode is intended to be used if the vehicle is in deep
snow, sand, or gravel conditions and more wheel spin
than ESC would normally allow is required to gain
traction. To turn ESC on again, momentarily press the
ESC OFF switch. This will restore the normal “ESC On”
mode of operation.
NOTE:
To improve the vehicle’s traction when driving with
snow chains, or starting off in deep snow, sand, or gravel, it
may be desirable to switch to the “Partial Off” mode by
pressing the ESC OFF switch. Once the situation requiring
ESC to be switched to the “Partial Off” mode is overcome,
turn ESC back on by momentarily pressing the ESC OFF

switch. This may be done while the vehicle is in motion.

ESC Activation/Malfunction Indicator Light And
ESC OFF Indicator Light
The “ESC Activation/Malfunction Indicator
Light” in the instrument cluster will come on
when the ignition switch is turned to the ON
position. It should go out with the engine
running. If the “ESC Activation/Malfunction Indicator
Light” comes on continuously with the engine running, a
malfunction has been detected in the ESC system. If this
light remains on after several ignition cycles, and the
vehicle has been driven several miles (kilometers) at
speeds greater than 30 mph (48 km/h), see your authorized
dealer as soon as possible to have the problem
diagnosed and corrected.
The “ESC Activation/Malfunction Indicator Light” (located
in the instrument cluster) starts to flash as soon as
the tires lose traction and the ESC system becomes active.
The “ESC Activation/Malfunction Indicator Light” also
flashes when TCS is active. If the “ESC Activation/
Malfunction Indicator Light” begins to flash during acceleration,
ease up on the accelerator and apply as little
throttle as possible. Be sure to adapt your speed and
driving to the prevailing road conditions.
NOTE:
The “ESC Activation/Malfunction Indicator Light”
and the “ESC OFF Indicator Light” come on momentarily
each time the ignition switch is turned ON.

Each time the ignition is turned ON, the ESC system
will be ON even if it was turned off previously.

The ESC system will make buzzing or clicking sounds
when it is active. This is normal; the sounds will stop
when ESC becomes inactive following the maneuver

that caused the ESC activation.
__________________
2013 Sahara Unlimited
Billet - Auto - 3.73 - Connectivity - Painted Hardtop - LSD - Remote Start - Saddle Leather - Side Airbags

I may mall crawl...but I look good doing it.....
panthermark is offline   Quote Quick Reply
Old 06-21-2013, 02:26 PM   #126
yeah,,,, im that good

5-Year WF Supporting Member
 
panthermark's Avatar
 
Join Date: Aug 2011
Location: Chicago-land
Posts: 9,866
Images: 13
The biggest benefit of LSD is that it is straight up mechanical. So the goal is basically to get traction before the nanny systems start to kick in. And if the nanny systems do kick in, they are less invasive because you already have torque transfer in place.
__________________
2013 Sahara Unlimited
Billet - Auto - 3.73 - Connectivity - Painted Hardtop - LSD - Remote Start - Saddle Leather - Side Airbags

I may mall crawl...but I look good doing it.....
panthermark is offline   Quote Quick Reply
Old 06-21-2013, 02:43 PM   #127
Jeeper
 
DC Dennis's Avatar
 
Join Date: Jul 2012
Posts: 379
All of that is the exact same stuff, traction control applications with different programming applying to different situations. Stability control, Anti-lock brakes, and traction control/eLDS/BLD/etc. There will be retarded throttle and applied brakes in each. The only traction control programing that does not really throttle back or apply the breaks is on high performance extics with launch control, but even that retards the engine to limit wheel spin, but gives you a 0-60/0-100 time that no human is fast enough to pull off.
DC Dennis is offline   Quote Quick Reply
Old 06-21-2013, 02:50 PM   #128
Jeeper
 
Join Date: Mar 2012
Posts: 252
Quote:
Originally Posted by LoCo Jeep View Post
My "being new" has no relevance in this conversation.
This is the first thing you have said that I agree with!
I think it has much more to do with a comprehension issue.

Oh and by the way most minivans are front wheel drive.
This is like trying to teach a Flight attendant how to fly the plane.

Lastly you are correct BLD is just like anti-spin.
Jeeps are just like minivans.

And welcome to our planet.
guppy is offline   Quote Quick Reply
Old 06-21-2013, 02:51 PM   #129
Jeeper
 
Join Date: Jun 2013
Location: Cedar Park, Tx.
Posts: 66
Quote:
Originally Posted by panthermark View Post


You are talking about JK's.....so your scenarios (for both open diff and LSD) will never happen unless you gun the engine and have pulled the fuse for your ESP. Have you ever tried to do a donut in a snowy parking lot in a Jeep with ESP/traction control not disengaged?

You are not going to spin a tire in one spot, nor are you going to fishtail on do a 360. You are just going to sit there with you ESP light flashing and you brake pads burning up.
True (doubt the brake pads will burn up but I get the point)....I was going back to my experience with my 1 Ton dually which will 360 at will when it's wet (LSD + ton's of torque plus little weight on rear tires).

So for city driving it seems like either with or without LSD we are counting on the "computers" to keep the vehicle under control and moving forward. I've had 4x4's but never a Jeep or for that matter any 4x4 with all of this computer aided traction wizardry.

Am I right in assuming that "on the street" LSD would get you moving quicker than the computer will and will save wear and tear on the brakes but there is no situation where an open diff + computers will leave you stranded while a LSD + computers won't?


This almost makes me want to drive out to the ranch and dig a mudhole and do some experimentation...(except we would need some rain for mud and that ain't happening).
__________________
2013 JKUR pulled by a
1984 BlueBird Wanderlodge 35 FCRB
BubbaEinstein is offline   Quote Quick Reply
Old 06-21-2013, 03:00 PM   #130
yeah,,,, im that good

5-Year WF Supporting Member
 
panthermark's Avatar
 
Join Date: Aug 2011
Location: Chicago-land
Posts: 9,866
Images: 13
Quote:
Originally Posted by BubbaEinstein View Post
True (doubt the brake pads will burn up but I get the point)....I was going back to my experience with my 1 Ton dually which will 360 at will when it's wet (LSD + ton's of torque plus little weight on rear tires).

So for city driving it seems like either with or without LSD we are counting on the "computers" to keep the vehicle under control and moving forward. I've had 4x4's but never a Jeep or for that matter any 4x4 with all of this computer aided traction wizardry.

Am I right in assuming that "on the street" LSD would get you moving quicker than the computer will and will save wear and tear on the brakes but there is no situation where an open diff + computers will leave you stranded while a LSD + computers won't?


This almost makes me want to drive out to the ranch and dig a mudhole and do some experimentation...(except we would need some rain for mud and that ain't happening).
I'd say that is mostly correct. In a severe situation (like being stuck), the factory LSD will help a little (it is pretty tame, a TT is much better)...but you will probably get more help from BLD, 4WD, and maybe someone with a tow strap. If you are losing control of the vehicle, LSD or not, the computer will kick in and try to save your hide.

Actually, the biggest difference maker in all of this is tires.
__________________
2013 Sahara Unlimited
Billet - Auto - 3.73 - Connectivity - Painted Hardtop - LSD - Remote Start - Saddle Leather - Side Airbags

I may mall crawl...but I look good doing it.....
panthermark is offline   Quote Quick Reply
Old 06-21-2013, 03:13 PM   #131
Jeeper
 
n00g7's Avatar
 
Join Date: Apr 2013
Location: Northern VT // Western Wisconsin
Posts: 1,995
Quote:
Originally Posted by DC Dennis View Post
All of that is the exact same stuff, traction control applications with different programming applying to different situations. Stability control, Anti-lock brakes, and traction control/eLDS/BLD/etc. There will be retarded throttle and applied brakes in each. The only traction control programing that does not really throttle back or apply the breaks is on high performance extics with launch control, but even that retards the engine to limit wheel spin, but gives you a 0-60/0-100 time that no human is fast enough to pull off.
A good eLSD (like that on a sports car, BMW/Audi/Merc) will not retard throttle with the other nannies off (if given the option). Jeep does not have this.

The BLD system is not a substitute for a fast acting eLSD. It is tuned for off-road 1 wheel with 0 traction conditions at slow speeds.

A mechanical LSD will never retard the throttle, which is why we are recommending it. The DSC will perform that operation if needed in the case where both wheels are slipping due to too much gas with the LSD.

__________________
That moment when you look at a really nice JK and think to yourself, "Well I SUPPOSE I could see myself trading in my TJ for one of those, but for those ugly ass door handles."
n00g7 is offline   Quote Quick Reply
Old 06-21-2013, 04:18 PM   #132
Jeeper
 
DC Dennis's Avatar
 
Join Date: Jul 2012
Posts: 379
Quote:
Originally Posted by n00g7 View Post
A good eLSD (like that on a sports car, BMW/Audi/Merc) will not retard throttle with the other nannies off (if given the option). Jeep does not have this.

The BLD system is not a substitute for a fast acting eLSD. It is tuned for off-road 1 wheel with 0 traction conditions at slow speeds.

A mechanical LSD will never retard the throttle, which is why we are recommending it. The DSC will perform that operation if needed in the case where both wheels are slipping due to too much gas with the LSD.

I meant it as an "and/or"
DC Dennis is offline   Quote Quick Reply
Old 06-21-2013, 05:04 PM   #133
Jeeper
 
Join Date: Nov 2010
Posts: 771
There's info missing out there. From my experience:

1. Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. The ESC
corrects for over/under steering of the vehicle by applying
the brake of the appropriate wheel to assist in
counteracting the over/under steer condition. Engine
power may also be reduced to help the vehicle maintain
the desired path.

This is when the squiggly car icon lights up (flashes on and off) on the instrument cluster, the abs kicks in loud and the throttle choked. I had to push it really hard in deep snow to invoke it.

2.Traction Control System (TCS)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s) to provide
enhanced acceleration and stability. A feature of the TCS
system functions similar to a limited slip differential and
controls the wheel spin across a driven axle. If one wheel
on a driven axle is spinning faster than the other, the
system will apply the brake of the spinning wheel. This
will allow more engine torque to be applied to the wheel
that is not spinning. This feature remains active even if
TCS and ESC are in either the “Partial Off” or “Full Off”
modes.

This is what I expect I have been experiencing of the past two winters, open diff, 2wd and 4wd with zero concern.

Out of all that muck, my understanding is BLD means just that, brake lock differential and the application of it as high lighted in the above.

The way everyone is talking BLD is only in the aggressive 1st scenario above, i.e. abs kicks in the vehicle is jerky, its loud and the engine gets throttled.

Doesn't sound right, BLD is on all the time, and if it is correct it is applied per 2. above gently as needed. What this violent combination of abs and engine throttling is called I don't think is BLD in the sense they are using it. BLD is in use but much more aggressively hence the panic use which is the abs kicking in, on normal use, just simple brake pressure is applied as warranted.
positrak is offline   Quote Quick Reply
Old 06-21-2013, 05:19 PM   #134
Jeeper
 
Join Date: Nov 2010
Posts: 771
Put is this way. BLD is on all the time, if you're turning a corner in the rain at 20 mph and the wheel slips, gentle pressure is applied. If you're off roading and at a 40 degree angle with two wheels on the ground, it will be applied aggressively which is abs level along with throttle reduction.

Unless this is completely incorrect BLD usage turning that corner at 20 mph in the rain and one wheel slips would have the system cut the throttle and brake hard where the abs invokes.

This is what needs to be cleared up. From experience I would suggest it is on all the time and gently applying the brakes as needed in any slip scenario. In a real slip scenario, full action will take place where brakes are applied to the abs level and the engine throttled.
positrak is offline   Quote Quick Reply
Old 06-21-2013, 05:45 PM   #135
Jeeper
 
NYJETS's Avatar
 
Join Date: Jun 2013
Location: FLORI-DUH
Posts: 431
My head hurts
NYJETS is offline   Quote Quick Reply
Old 06-21-2013, 05:47 PM   #136
Jeeper
 
Join Date: May 2013
Posts: 166
Quote:
Originally Posted by nyjets View Post
my head hurts
+1 !
Postmon is offline   Quote Quick Reply
Old 06-21-2013, 05:48 PM   #137
Jeeper
 
NYJETS's Avatar
 
Join Date: Jun 2013
Location: FLORI-DUH
Posts: 431
At what mileage should the Diff fluids be changed? I have LSD so I guess I need a special fluid for that????
NYJETS is offline   Quote Quick Reply
Old 06-21-2013, 05:53 PM   #138
Jeeper
 
n00g7's Avatar
 
Join Date: Apr 2013
Location: Northern VT // Western Wisconsin
Posts: 1,995
Quote:
Originally Posted by positrak View Post
Put is this way. BLD is on all the time, if you're turning a corner in the rain at 20 mph and the wheel slips, gentle pressure is applied. If you're off roading and at a 40 degree angle with two wheels on the ground, it will be applied aggressively which is abs level along with throttle reduction.

Unless this is completely incorrect BLD usage turning that corner at 20 mph in the rain and one wheel slips would have the system cut the throttle and brake hard where the abs invokes.

This is what needs to be cleared up. From experience I would suggest it is on all the time and gently applying the brakes as needed in any slip scenario. In a real slip scenario, full action will take place where brakes are applied to the abs level and the engine throttled.
LSD transfers torque from one wheel to the other, BLD sucks up a portion of the delivered torque through the brakes such that both wheels rotate at the same speed.

In a typical scenario where 1 wheel can handle 50lbs (e.g., it's on ice) and the other needs 100lbs (on pavement) to begin moving you uphill, the BLD applies 50lbs of brake pressure to the 50lbs wheel -- thus total engine output would need to be 200 ft lbs.

In an LSD, say a 2:1, the wheel on ice gets 50 and the other gets 100 (maximum, for a 2:1). Engine output need only be 150ft-lbs for the same movement.

Someone go turn off DSC et al in their jeep except for BLD and pop the clutch with one wheel on the grass so we can see how long it takes to kick in. If it's longer than instantly, you have your answer to the above.
__________________
That moment when you look at a really nice JK and think to yourself, "Well I SUPPOSE I could see myself trading in my TJ for one of those, but for those ugly ass door handles."
n00g7 is offline   Quote Quick Reply
Old 06-21-2013, 06:01 PM   #139
Jeeper
 
Join Date: Nov 2010
Posts: 771
Good test. While the tester is at it, check the rpms for both, which is higher which is lower in order to get going.
positrak is offline   Quote Quick Reply
Old 06-21-2013, 06:07 PM   #140
yeah,,,, im that good

5-Year WF Supporting Member
 
panthermark's Avatar
 
Join Date: Aug 2011
Location: Chicago-land
Posts: 9,866
Images: 13
Quote:
Originally Posted by positrak View Post
There's info missing out there. From my experience:

1. Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. The ESC
corrects for over/under steering of the vehicle by applying
the brake of the appropriate wheel to assist in
counteracting the over/under steer condition. Engine
power may also be reduced to help the vehicle maintain
the desired path.

This is when the squiggly car icon lights up (flashes on and off) on the instrument cluster, the abs kicks in loud and the throttle choked. I had to push it really hard in deep snow to invoke it.

2.Traction Control System (TCS)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s) to provide
enhanced acceleration and stability. A feature of the TCS
system functions similar to a limited slip differential and
controls the wheel spin across a driven axle. If one wheel
on a driven axle is spinning faster than the other, the
system will apply the brake of the spinning wheel. This
will allow more engine torque to be applied to the wheel
that is not spinning. This feature remains active even if
TCS and ESC are in either the “Partial Off” or “Full Off”
modes.

This is what I expect I have been experiencing of the past two winters, open diff, 2wd and 4wd with zero concern.

Out of all that muck, my understanding is BLD means just that, brake lock differential and the application of it as high lighted in the above.

The way everyone is talking BLD is only in the aggressive 1st scenario above, i.e. abs kicks in the vehicle is jerky, its loud and the engine gets throttled.

Doesn't sound right, BLD is on all the time, and if it is correct it is applied per 2. above gently as needed. What this violent combination of abs and engine throttling is called I don't think is BLD in the sense they are using it. BLD is in use but much more aggressively hence the panic use which is the abs kicking in, on normal use, just simple brake pressure is applied as warranted.
Brake Lock Differential is the off-road programming of Traction Control.

BLD is part of Traction Control, which is linked to ECS.
ECS is the part that reduces power to the engine (ERM reduced engine power as well).

Whenever Traction Control or ECS are used, the ECS light will show.

From the OM:
The “ESC Activation/Malfunction Indicator Light” also
flashes when TCS is active. If the “ESC Activation/
Malfunction Indicator Light” begins to flash during acceleration,
ease up on the accelerator and apply as little
throttle as possible. Be sure to adapt your speed and
driving to the prevailing road conditions.



2013 Wrangler Unlimited | Accident Avoidance Features | Jeep
Electronic Stability Control+is specially tuned for performance handling so you can switch it off. In addition, All-Speed Traction Control works in tandem with Electronic Stability Control. It has a special set of calibrations specifically for driving in 4LO. To help crawl over obstacles and during heavy articulation activity, it applies the brakes more aggressively and for longer duration than traction control.

The bolded would be your BLD...the actual programming.

If you are talking about normal driving and a spinning wheel being braked, that is Traction Control (I think you are calling that BLD...the process of a wheel being braked)...and when that happens, your ESC light will flash.
__________________
2013 Sahara Unlimited
Billet - Auto - 3.73 - Connectivity - Painted Hardtop - LSD - Remote Start - Saddle Leather - Side Airbags

I may mall crawl...but I look good doing it.....
panthermark is offline   Quote Quick Reply
Old 06-21-2013, 06:14 PM   #141
Jeeper
 
Join Date: Nov 2010
Posts: 771
This is the murk or muck that needs to be clarified, and what I also want to know. Forget the marketing speak from Jeep. Is the application of the brakes being applied to a wheel that is losing traction, applicable at any speed and is that what is known as BLD.

Again all I can say is that with open diffs in both 4wd and 2wd in two monster winters, never once did I slide, slip lose traction in any usage of the vehicle whatsoever. And this coming from an old wrangler with LSD that couldn't move and inch in 2wd in glassed snow.
positrak is offline   Quote Quick Reply
Old 06-21-2013, 06:38 PM   #142
Jeeper
 
n00g7's Avatar
 
Join Date: Apr 2013
Location: Northern VT // Western Wisconsin
Posts: 1,995
Quote:
Originally Posted by positrak View Post
This is the murk or muck that needs to be clarified, and what I also want to know. Forget the marketing speak from Jeep. Is the application of the brakes being applied to a wheel that is losing traction, applicable at any speed and is that what is known as BLD.

Again all I can say is that with open diffs in both 4wd and 2wd in two monster winters, never once did I slide, slip lose traction in any usage of the vehicle whatsoever. And this coming from an old wrangler with LSD that couldn't move and inch in 2wd in glassed snow.

The fact that you're making this comparison between the TJ and JK means that you don't understand the different systems' functions and why that would be the case (ignoring the more important factors of weight and tires).

If you floored it on grass in your TJ w/ LSD you wouldn't move anywhere and both tires would spin.
If you floored it on grass in your JK (ignoring BLD) w/ LSD, you would start spinning both tires and throttle would be neutered and you'd be off on your way.
If you floored it on grass in your JK w/o LSD, you would spin a single tire, throttle would be neutered and you'd be off.
If you floored it on grass in your JK w/o LSD and w/ traction control off, you would spin the tire again, BLD would detect and start braking the spinning tire to deliver more power to the other wheel. As soon as that other wheel starts spinning, same thing again -- rinse and repeat, not nearly as graceful as a mechanical LSD because you're dealing with almost binary functionality on low traction surfaces, which is why BLD appears eclectic on soft surfaces and appears jerky on rocks because it's intent is to mimic lockers with full wheel braking on one side.
__________________
That moment when you look at a really nice JK and think to yourself, "Well I SUPPOSE I could see myself trading in my TJ for one of those, but for those ugly ass door handles."
n00g7 is offline   Quote Quick Reply
Old 06-21-2013, 06:41 PM   #143
yeah,,,, im that good

5-Year WF Supporting Member
 
panthermark's Avatar
 
Join Date: Aug 2011
Location: Chicago-land
Posts: 9,866
Images: 13
The owners manual is specific (even if consfusing) about this.

Normally, ESC and TCS are "on".

In 2WD, there are two modes avaiable.

ESC "on" (which includes TCS), and ESC "partial off" (which disables TCS and allows for wheel spin). You can't have wheel spin with BLD.

In 4L, there is only mode, ESC "off". In this mode, ESC is all the way off, the TCS is off except for the "limited slip" function (this would be BLD).

In 4H, there are three modes. ESC "on", ESC "partial off", and ESC "off". The work the same as above.

Being that all "city" driving will be done in 2WD. Your options are TCS "on" (normal) or TSC off (called ESC "partial off"....for wheel spin).

Again, whenver TCS is used, your ESC light will flash.

--------------
The problem with the Wrangler (for doing donuts) is that you either have BLD, Traction Control or ESC on. I don't think there is a mode that turns all of them off. However, I think that prior to 2011 (or 2012), it was easier to get the systems off (steering wheel dance). I'll have to check.
__________________
2013 Sahara Unlimited
Billet - Auto - 3.73 - Connectivity - Painted Hardtop - LSD - Remote Start - Saddle Leather - Side Airbags

I may mall crawl...but I look good doing it.....
panthermark is offline   Quote Quick Reply
Old 06-21-2013, 06:46 PM   #144
Jeeper
 
Join Date: Nov 2010
Posts: 771
YJ actually.

Didn't read beyond your mistake.

Look, friend, this isn't a competition on who is "right" or who is "wrong".

I'm giving you my real world experiences. What actually happens on the ground, despite what the "glossy" brochure says or the academic theses proffered.

Similar to the hysterics that a CAI on the jeep cannot do anything, without that person having ever removed the stock one and noted its purpose build sound muffling incarnation.
positrak is offline   Quote Quick Reply
Old 06-21-2013, 06:57 PM   #145
Jeeper
 
n00g7's Avatar
 
Join Date: Apr 2013
Location: Northern VT // Western Wisconsin
Posts: 1,995
Quote:
Originally Posted by positrak View Post
YJ actually.

Didn't read beyond your mistake.

Look, friend, this isn't a competition on who is "right" or who is "wrong".

I'm giving you my real world experiences. What actually happens on the ground, despite what the "glossy" brochure says or the academic theses proffered.

Similar to the hysterics that a CAI on the jeep cannot do anything, without that person having ever removed the stock one and noted its purpose build sound muffling incarnation.
I made a guess, figured you had a TJ. The list of results I listed is what would happen, take it or leave it.

There is a reason why RWD vehicles have an LSD: because it gets busy at the back to put the power down and Stability Control is there to save your ass if you overdo it.
__________________
That moment when you look at a really nice JK and think to yourself, "Well I SUPPOSE I could see myself trading in my TJ for one of those, but for those ugly ass door handles."
n00g7 is offline   Quote Quick Reply
Old 06-21-2013, 07:00 PM   #146
Jeeper
 
Join Date: Nov 2010
Posts: 771
Understood.

Big question to you is. Have you actually tried this all with your 2012+ Jeep Wrangler?
positrak is offline   Quote Quick Reply
Old 06-21-2013, 08:35 PM   #147
Jeeper
 
DC Dennis's Avatar
 
Join Date: Jul 2012
Posts: 379
Quote:
Originally Posted by positrak View Post
Good test. While the tester is at it, check the rpms for both, which is higher which is lower in order to get going.
RPM has to do with HP, NOT torque
DC Dennis is offline   Quote Quick Reply
Old 06-22-2013, 06:21 AM   #148
Jeeper
 
Fellows's Avatar
 
Join Date: Jun 2012
Posts: 419
Positrac- I don't know if you mentioned it already or not, but when you were driving in the snow, did the TCS light come on at all? If it was deep snow, it could just be the MTs had good traction the entire time, thus no TCS of any kind would be needed.

Also I think BLD had been used incorrectly this entire thread. From the discussion from the Jeep engineer referenced earlier , it mimics lockers not LSD. The owner's manual states TCS is the system that mimics LSD. TCS doesn't lock the brake, it just gradually applies it to get the wheels to spin at the same rate. If that's not working, it starts cutting the throttle. You're not guaranteed throttle reduction every time the TCS kicks in. In my mind its not much different then the clutch packs in the LSD in that slowing down the faster wheel so that both turn at the same time is key to getting traction back. The main advantage of the LSD is some of the friction from the clutch pack is being transferred to the slower wheel to speed it up while simultaneously slowing down the spinning wheel so that they meet at the same wheel speed sooner. Depending on well the TCS software is and how poor the LSD mechanicals are the effects could be negligible (sensors can detect wheel slip and other conditions much sooner than than centrifugal force can start working the LSD mechanics) . Maybe it's a 1/10th faster? 2 seconds? 1 nano second? Who knows? If it saved me a nano second of traction response and cost $300 and add one more thing to maintain, I might find that a debatable value. Since its hard to find someone who has had similar JK's ,one with, one without LSD, with the same conditions try each out and give real world feedback it's hard to say.
Fellows is offline   Quote Quick Reply
Old 07-25-2013, 07:03 PM   #149
Jeeper
 
Afrotango's Avatar
 
Join Date: May 2012
Location: Cape Town
Posts: 16
hello all. What is "tru-lok"? is it a diff lock?
__________________
2010 Mango Tango "Mountain"
2.5 Lift with Rancheros at the rear ,procomp up front.
BFG mud terrains.
Afrotango is offline   Quote Quick Reply
Old 07-25-2013, 08:05 PM   #150
yeah,,,, im that good

5-Year WF Supporting Member
 
panthermark's Avatar
 
Join Date: Aug 2011
Location: Chicago-land
Posts: 9,866
Images: 13
Quote:
Originally Posted by Afrotango View Post
hello all. What is "tru-lok"? is it a diff lock?
Tru Lok = Locking differentials in the Rubi
Trac Lok = Antispin/Limited Slip differential available on the Sport and Sahara
Rock Trac = 4:1 Rubicon transfer case
Tru Trac = Eaton/Detroit Limited Slip Differential
Command Trac = 2.72:1 Tranfer case in the Sport and Sahara

__________________
2013 Sahara Unlimited
Billet - Auto - 3.73 - Connectivity - Painted Hardtop - LSD - Remote Start - Saddle Leather - Side Airbags

I may mall crawl...but I look good doing it.....
panthermark is offline   Quote Quick Reply
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Download our Mobile App

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 06:25 PM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC