Gear Oil... what works best with LSD? - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > JK Jeep Wrangler Forum > JK Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 11-18-2014, 04:14 PM
Thread Starter
  #1
Jeeper
 
numbah1's Avatar
 
Join Date: Aug 2013
Posts: 666
Gear Oil... what works best with LSD?

Okay so I just regeared from 3.21 to 4.88's. I also put in Detroit Truetracs (front/rear) on my 2012 JKU (automatic). With about 250 miles on the ODO since the regear I need to start getting new oil in there.

I've searched the forum and there isn't a dedicated thread regarding the break-in of new gears and what oil should go in. I've heard of full synthetic and the same argument for dino. Problem is that I can't seem to get an answer as to what gear oil is recommended for best results with a limited slip differential.

Can anyone tell me? I have been running RP since I bought my rig last June (in my differentials) but with these new Yukon gears I just don't know what I should be buying. Looking to make a decision soon--- help this "somewhat new" Jeeper make the right choice!

numbah1 is offline   Quote
Old 11-18-2014, 04:31 PM   #2
Jeeper
 
DryCreek's Avatar
 
Join Date: Sep 2014
Posts: 877
Quote:
Originally Posted by numbah1 View Post
Okay so I just regeared from 3.21 to 4.88's. I also put in Detroit Truetracs (front/rear) on my 2012 JKU (automatic). With about 250 miles on the ODO since the regear I need to start getting new oil in there.

I've searched the forum and there isn't a dedicated thread regarding the break-in of new gears and what oil should go in. I've heard of full synthetic and the same argument for dino. Problem is that I can't seem to get an answer as to what gear oil is recommended for best results with a limited slip differential.

Can anyone tell me? I have been running RP since I bought my rig last June (in my differentials) but with these new Yukon gears I just don't know what I should be buying. Looking to make a decision soon--- help this "somewhat new" Jeeper make the right choice!
Have you checked the Yukon website?

JK Differential Oils

Also,from their website:
New Gear Break-In
All new gear sets require a break-in period to prevent overheating damage. Any overloading
or overheating will break down the gear oil, which will cause the ring and pinion to fail.
This can be determined by inspection and will void the gears’ warranty.

Please follow these guidelines to insure proper break-in.
- Avoid heavy acceleration during the break-in process.
- Drive the vehicle lightly for the first 15 to 20 miles and stop. Let the differential cool
before proceeding.
- Avoid heavy acceleration for the first 100 miles.
- Drive the vehicle at least 500 miles before towing to retain the gears’ warranty.
- When towing for the first time, drive for a very short distances (less than 15 miles) with
the full load and stop. Let the differential cool for about 20 minutes before proceeding.
Repeat this procedure two more times (45 miles total) to fully break in the gears.
- Change the oil after the first 500 miles. This will remove any metal particles and phosphoric
coating shed by the gear set during the gears’ break-in period.
These towing instructions may seem unnecessary to most people, but we have seen
many differentials damaged from being loaded before the gear set was fully broken-in.
Overloaded or overheated gear oil will break down and destroy the ring and pinion!

Yukon General Installation Instructions (674 KB)

__________________
2011 Jeep Wrangler Sahara-JK, 6 spd., 1995 Jeep Wrangler S, 2.5, 4 cyl., 2010 Chrysler 300 Touring/Signature Edition, 2003 2500 SLT, QC, LB, ETH, DEE, 2006 Winnebago Sightseer 29R (F53/V10/5spd TQShift) 2002 Nissan Xterra 4WD/V6
Other: 2010 Kubota MX4700 with FEL, 1977 Kubota L185.
DryCreek is offline   Quote
Old 11-18-2014, 04:33 PM   #3
Jeeper
 
Potatohead's Avatar
 
Join Date: Nov 2014
Location: Vancouver
Posts: 1,093
It's not so much the fluid (use any brand you wish) but it's an additive that needs to be added to it. Some fluids will have this already, so you'll need to read the bottle. If it doesn't, you can buy it separately and then take out the appropriate amount of diff fluid to compensate.
Potatohead is offline   Quote
Sponsored Links
Advertisement
 
Old 11-18-2014, 04:47 PM   #4
BE AWARE OF THE DRAGON..

5-Year WF Supporting Member
WF Lifetime Member
 
Old Dogger's Avatar
 
Join Date: May 2012
Location: Hot as Hell Arizona, the home of the mighty Dragon. Beware of your surrounding, because of DANGER!
Posts: 31,004
The oil Brand is a choice.
Just make sure that the bottle so states, that it already has the additive in it.
Again, synthetic, or conventional, is also a choice.

I like synthetic 75W-140, in the rear diff!!!!!!!!!!
__________________
1974 CJ5, 2003 TJ, 2013 2 door Black Rubicon, auto, with 4.10 ratio.
Shaking at 40-70 MPH, Read this!!!

The Mighty Grizzly is not concerned,
with
the needs of the Hunter....


Click here and become a WF supporting Member
Old Dogger is online now   Quote
Old 11-18-2014, 05:04 PM   #5
Jeeper
 
Join Date: Jun 2013
Location: SE Michigan
Posts: 1,401
Make sure you use appropriate gear oil for the TrueTracs:

Quote:
Eaton Detroit Truetrac FAQ’s

What kind of oil should I use? Can I use synthetic? Do I need friction additive/modifier?

A quality petroleum/mineral based oil works best in the Truetrac units. We do not recommend synthetic oil. Friction additive/modifier is not required.
Source: Eaton Detroit Truetrac Differentials - West Coast Differentials

More strictly than "friction modifiers not required", I've even seen mentions that friction modifiers are to be AVOIDED for TrueTracs, because they limit the LSD functionality.
__________________
2013 Wrangler Sport (2DR) | Stick Shift | 4.10 Gears | TrueTrac LSD Front & Rear
33x12.5x15 Duratracs on 15x8 Black Rock D-Window Wheels
Prodigy Performance Stage 2 Turbo
AEV 2" Spacer Lift
Full Disclosure: Affiliated with Prodigy Performance as of 3/10/16 (explanation)
This is my personal account. My statements/opinions are my own; not Prodigy's
UselessPickles is offline   Quote
Old 11-18-2014, 05:12 PM
Thread Starter
  #6
Jeeper
 
numbah1's Avatar
 
Join Date: Aug 2013
Posts: 666
Thanks for the replies, everyone.

Yes I have checked Yukon's website and read exactly what was posted.

I guess I'm just really looking for specifics as to what everyone here is actually using in their rigs. I'm not doing any kind of towing so would you think 75-140 is still beneficial? I wheel about once a month and this is also my DD.

Performance and longevity is the main goal here so does anyone have names of products that they are using now?... something like, "I'm using Amsoil 75w-90 full synthetic because..." or "if I were you, I'd just use (insert brand) because it...".

Thanks again, guys. I look to you seasoned Jeepers for advice all the time and you guys never fail to produce.
numbah1 is offline   Quote
Old 11-19-2014, 04:29 AM
Thread Starter
  #7
Jeeper
 
numbah1's Avatar
 
Join Date: Aug 2013
Posts: 666
No one else?
numbah1 is offline   Quote
Old 11-19-2014, 07:07 AM   #8
Jeeper

WF Supporting Member
 
Barmanvarn's Avatar
 
Join Date: Sep 2011
Location: Sherwood, AR
Posts: 5,474
Quote:
Originally Posted by UselessPickles View Post
Make sure you use appropriate gear oil for the TrueTracs: More strictly than "friction modifiers not required", I've even seen mentions that friction modifiers are to be AVOIDED for TrueTracs, because they limit the LSD functionality.
Agreed.

I read that as well when I installed a TruTrac a few years ago. I don't use friction additive and have had zero problems.
__________________
-Brian
2012 Cherry Red JK
TF 2.5 Coils w/ Billstein 5100 Shocks
17x8 Black Rock D-Window Alloys
315/70/17 GY Duratracs
4:56 Gears - LSD in Rear w/ Ten Factory Chromoly Shafts
TF HD Diff Covers
Barmanvarn is offline   Quote
Old 11-19-2014, 01:18 PM   #9
Newb
 
Join Date: Nov 2014
Location: Thornton, CO
Posts: 12
Royal Purple is what I use. It's a little pricey, but I've always subscribed to the theory 'you get what you pay for'. Also, no additive is required with RP.
Hope this helps!
__________________
It's more than a 'Jeep Thing'!
COBob is offline   Quote
Old 11-19-2014, 08:59 PM
Thread Starter
  #10
Jeeper
 
numbah1's Avatar
 
Join Date: Aug 2013
Posts: 666
Yeah, I've been using Royal Purple for awhile now. Just didn't know if I should be using something else now that I have front & rear Truetrac's.

I've decided that I'm going to use synthetic oil though.
numbah1 is offline   Quote
Old 11-19-2014, 10:05 PM   #11
Jeeper
 
Smitty4x4's Avatar
 
Join Date: Jul 2012
Posts: 536
Just get one that doesn't have friction modifier. If the bottle says not required, does that mean it has it already added? I would find this out before using the oil or get one that has to have modifier added and just don't put any in. This way you know it doesn't have it. Friction modifier is for clutch type LSDs. As far as 90 vs 140, if you tow or load your Jeep with lots gear or anything else that weighs it down, I would go with 140 for the protection of the gears. If you are normally empty with just you or a couple of people then 90 will give you SLIGHTLY better economy if you can even measure it and depending on who you ask SLIGHTLY better performance. I currently use Mobile 1 75W-140 in mine.
Smitty4x4 is offline   Quote
Old 11-19-2014, 11:08 PM
Thread Starter
  #12
Jeeper
 
numbah1's Avatar
 
Join Date: Aug 2013
Posts: 666
I was looking at the Mobil 1 75w-90 that has the LS for limited slip on the label.

That's probably going to be the route I'm taking. Thanks for the reply!
numbah1 is offline   Quote
Old 11-20-2014, 12:03 AM   #13
Jeeper
 
Smitty4x4's Avatar
 
Join Date: Jul 2012
Posts: 536
Well hold on a minute. I do not have a limited slip. If Detroits are not supposed to use friction modifier, it may not be the right choice for you. Maybe a Trutrac guru will weigh in here. Since trutracs are gear driven and all other common limited slips use a friction based principle, this may be area where there may be only a few oil choices. I am considering an Eaton E-locker or Trutrac for my rear axle so I am also interested in this as well.
It looks like I'm going to have to do some research. I'll post back if I find before somebody who knows gives us an answer. The question is, does LS or no modifier needed mean that the oils already has it added or is it simply not needed when using that oil? If it is already added and Detroit say it isn't recommended, then we need to look further.
Smitty4x4 is offline   Quote
Old 11-20-2014, 12:44 AM   #14
Jeeper
 
Smitty4x4's Avatar
 
Join Date: Jul 2012
Posts: 536
From Eaton's website FAQ's:
"Detroit TrueTrac

What kind of oil should I use? Can I use synthetic? Do I need friction additive/modifier?
A quality petroleum/mineral based oil works best in the Truetrac units. We do not recommend synthetic oil. Friction additive/modifier is not required."
So it looks like plain old standard gear oil is actually best for this application.
Another interesting note is in the owners manual. They state that max tire size is 32" and any increase in size may void the warranty.
Smitty4x4 is offline   Quote
Old 11-20-2014, 09:33 AM
Thread Starter
  #15
Jeeper
 
numbah1's Avatar
 
Join Date: Aug 2013
Posts: 666
Well damn.
All of the guys in my local Jeep club say they all use synthetic. I made it clear what I'm running in my differentials and still the verdict was synthetic.
Starting to wonder about their level of expertise. Choosing the wrong oil is kind of a big deal when you're screwing around with expensive components. Guess if it's someone else's money who gives a shit, right?
numbah1 is offline   Quote
Old 11-20-2014, 10:47 AM   #16
Jeeper
 
Smitty4x4's Avatar
 
Join Date: Jul 2012
Posts: 536
Synthetic oil is better in most situations however the shock properties of conventional oil when used in differentials is more desirable for this application. Basically synthetic is to slippery and this differential benefits from the thicker cushioning properties of conventional oil. Since the differential still uses a friction principle as it engages, the conventional oil will allow the Truetrac to transfer more torque and do so more efficiently. I have seen the OEM tracloc have almost no noticeable torque transfer when using high end synthetic oil. When I cleaned out the diff in my TJ and put Dino oil in it, the Tracloc, while still not as good as a locker was functioning again. It seems that the Truetrac needs the same treatment. Since most of the club guys run lockers or open diffs, they may not have researched the LSDs thoroughly. Most of the info I found last night was from the Mustang and Camaro drag racing groups. It makes me wonder if more Jeep guys would be happier with LSD performance by swapping the oil.

FWIW I did find where the ELocker is now warrantied for use with 38" tires in the D44 application. The 32" limitation is on old warranty cards that havent been changed. I have not been able to confirm the same for the Truetrac.
Smitty4x4 is offline   Quote
Old 11-20-2014, 11:37 AM
Thread Starter
  #17
Jeeper
 
numbah1's Avatar
 
Join Date: Aug 2013
Posts: 666
Thanks for your research, Jeep brother.

I have been considering even jumping on 38's for my next set. What do you recommend in upgrading before I do this? I already have steel-braided extended brake lines and upgraded (Alloy USA) ball joints installed a few months ago. Lift wise I'm guess at least 4" but what about the axles? Should I just get RCV's and be done with it or do I also need to sleeve and gusset along with upgraded driveline's? If that is so then we're talking well over $2K.
numbah1 is offline   Quote
Old 11-20-2014, 12:22 PM   #18
Jeeper
 
Smitty4x4's Avatar
 
Join Date: Jul 2012
Posts: 536
I haven't done much research in the realm of 38" tires as I will never go larger than the 33"-34" range. I do know that I wouldn't run a Dana 30 with a tire that large even with the upgrades. 35's is about the most anybody that know would reccomend on a D30 and that is with the upgrades you mentioned. With 37"-40" by the time you spend what you need to get a D44 up to the task, I suspect that most would reccomend a D60 front and rear. Going larger than 35" usually becomes a deep pocket venture on a Jeep that is not a daily driver.
Smitty4x4 is offline   Quote
Old 11-20-2014, 03:19 PM
Thread Starter
  #19
Jeeper
 
numbah1's Avatar
 
Join Date: Aug 2013
Posts: 666
Noted.

I do have a buddy though that has been running 37's on his rig with his Dana 30 and the only thing he has done is sleeve and gusset. And he actually wheels his rig too without any problems. Maybe he's either very lucky or the the trails he's attacking is way mild.

I know I'm going to sleeve/gusset mine along with the front/rear truss and throw in RCV axle shafts, too. That'll pretty much sum up my armoring on the axles though.

numbah1 is offline   Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not 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






All times are GMT -5. The time now is 04:12 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.1
User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, Gladiator, Mopar and Grand Cherokee are copyrighted and trademarked to FCA US LLC.
Wranglerforum.com is not in any way associated with FCA US LLC.