New 35's put on with 4:88 gears - 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 05-27-2013, 07:26 PM   #1
Jeeper
 
NU2DAWAVE's Avatar
 
Join Date: May 2013
Posts: 53
New 35's put on with 4:88 gears

What is the recommended top speed MPH would be safe

NU2DAWAVE is offline   Quote Quick Reply
Old 05-27-2013, 07:27 PM   #2
ESP
Jeeper
 
ESP's Avatar
 
Join Date: Jun 2010
Location: NC
Posts: 11,480
Hi NU2DAWAVE, that's kinda a loaded question. Safe speed could be a number of speeds. What exactly are you trying to figure?

__________________
98 XJ 02 TJ 10 JK 13 JK

2013 JK - Lifted w/ 35s - Bilstein 5100s - Monster TB - Chopped Flares - Can't Keep It Clean
ESP is offline   Quote Quick Reply
Old 05-27-2013, 07:32 PM   #3
Jeeper
 
live_slow's Avatar
 
Join Date: Apr 2013
Posts: 666
Tires have a speed rating code on them:

Tire code - Wikipedia, the free encyclopedia

For example Goodyear Duratrac 33" is coded Q for 100 mph.

So I suppose in perfect conditions, with a tail wind, downhill, on a closed course, and an ambulance and fire team on standby, I could drive 100 MPH with my tires and they wouldn't explode.

Your tires will have a code in their specs.
__________________
IIIIII

Just another Billet Silver Metallic. It blends.
2013 | JK | 23R | 2"M | 33s on 15s |
live_slow is offline   Quote Quick Reply
Old 05-27-2013, 07:34 PM   #4
Jeeper
 
NU2DAWAVE's Avatar
 
Join Date: May 2013
Posts: 53
Driving on highway not to blow any seals and so on
NU2DAWAVE is offline   Quote Quick Reply
Old 05-27-2013, 07:38 PM   #5
Jeeper
 
NU2DAWAVE's Avatar
 
Join Date: May 2013
Posts: 53
Sorry I should of been more specific (live slow) I meant like blowing a trany or something mechanical
NU2DAWAVE is offline   Quote Quick Reply
Old 05-27-2013, 07:47 PM   #6
Jeeper
 
damndirtydog's Avatar
 
Join Date: Aug 2011
Location: Eden Utah
Posts: 1,655
A jeep that can go 100mph?! I'll believe it when I see it.
Jeeps have a fail safe mechanisim so a situation like that would never happen, it's called a non aerodynamic refrigerator box body style and a V6 engine.
The one time I hit 85 mph in mine I had to seek help for post traumatic stress syndrome, it was real scarey.
Probably would even worry about that silly stuff New2dawave.
damndirtydog is offline   Quote Quick Reply
Old 05-27-2013, 07:48 PM   #7
Jeeper
 
live_slow's Avatar
 
Join Date: Apr 2013
Posts: 666
I see now.

You can use a good gear calculator online, fill out all your components, tire size and ratio to see where you are at, RPM wise. Gear Ratio Calculator


Maybe check into an AEV procal or similar to set your computer for the new modifications.

The ballpark way to look at this is that since you went up in tire size and up to 4.88, you may find the vehicle is "running the same" as about 4.10/4.56 with a 32/33 inch tire. Probably similar to 4.56 and 33, not in terms of weight, but in terms of RPM at a certain gear and speed or even crawl ratio. Not exact, but close. You can figure the math on the calculator.

I think the gear/tire "sweet spot" for daily driving on 4.88 would be 37, but that's a little subjective really. There are folks running your combo out there who can offer their results.

Edit: here's a thread about it from the past http://www.wranglerforum.com/f33/4-5...on-239938.html
__________________
IIIIII

Just another Billet Silver Metallic. It blends.
2013 | JK | 23R | 2"M | 33s on 15s |
live_slow is offline   Quote Quick Reply
Old 05-27-2013, 07:54 PM   #8
Supporting Member

WF Supporting Member
 
Gunner's Avatar
 
Join Date: Jun 2012
Location: Seal Beach
Posts: 7,001
Stick or Auto and what year are you driving?
Gunner is offline   Quote Quick Reply
Old 05-27-2013, 08:11 PM   #9
Jeeper
 
tluke's Avatar
 
Join Date: Dec 2011
Location: Northwest PA
Posts: 42
I have a 2013 with 35's and the 6 speed manual. I went with 4.88's because the 4.56's were not available at the time. It's fine around town but on the highway at 70mph I am turning 3000rpm. 65 mph seems more comforable for long hauls. That drops the rpm closer to 2600 rpm. 1st gear is a bit low on the street so sometimes I start out in 2nd. Other than that no real regrets. I used the Procal and it worked like a charm.
tluke is offline   Quote Quick Reply
Old 05-27-2013, 11:19 PM   #10
Jeeper
 
NU2DAWAVE's Avatar
 
Join Date: May 2013
Posts: 53
Hey great info I have received, I was worried for nothing thanks you all for all the information by the way is an automatic
NU2DAWAVE is offline   Quote Quick Reply
Old 05-27-2013, 11:59 PM   #11
Jeeper
 
mckey73's Avatar
 
Join Date: Mar 2012
Location: La La Land
Posts: 9,751
113 mph in a '12 JKU with 3.73's and a manual @ 6,000 ft. I think it woulda done better with 4.10's, as I was having trouble in both 4th and 5th. That's alot of wind to push!
__________________
“Animals don't hate, and we're supposed to be better than them.”

-Elvis Presley
mckey73 is offline   Quote Quick Reply
Old 05-28-2013, 12:04 AM   #12
Jeeper
 
rics1997's Avatar
 
Join Date: Oct 2010
Location: Bristol, Tn
Posts: 4,764
I have had mine up to 85 several times with no issues and it ran smooth. I have 35 with 4.88. Only issue I have with that speed is the RPM's are getting up there. I could have easily went faster though. Run it regularly at 75mph going down the Interstate.
__________________
2010 Dark Charcoal Pearl Jeep Wrangler Sport S Automatic
4.88 Yukon w/Trac-Lok rear and Eaton ELocker Front - Synergy Gussets - B&M 70264 Trans Cooler
BDS 3" lift - BDS Fox 2.0 Racing Shocks
XHD front Bumper - Trektop NX - Goodyear MT/R w/Kevlar 35X12.5X15 on MB Chaos 5 Wheels - Thrush Turbo Muffler

Become a WranglerForum Supporting Member!
rics1997 is offline   Quote Quick Reply
Old 08-18-2013, 02:24 PM   #13
Jeeper
 
NU2DAWAVE's Avatar
 
Join Date: May 2013
Posts: 53
Ok now a late update the reason I asked or put up this post: we wife and I had trusted on our sales person and judgements on what to put on our Jeep with understanding of loss of MPG and so forth but when we got our JK back it broke down. The rear differential felt like something when loose and started to whine, on my way to a fishing trip two hours into the drive I had to turn back and take it back to the shop. After a week of waiting we got it back on a Thursday so I drove it to work on Friday same thing happened so here we go again back to the shop a week later my wife picks it up by the time I get home she tells me it's making a loud noise. So I get in and it sounded like a freight train right outer bearing went out also busted left outer seal of axle. Now they tow it back to the shop for another week, we have it now and everything is fine except that I have a seepage on top of the differential (front). I believe they made a hole for the air locker then decided to relocate the hole where it is now anyhow were happy to have our Jeep back and everything is fine except the leak lol so that is why I made this post thinking we were at fault
NU2DAWAVE is offline   Quote Quick Reply
Old 08-18-2013, 02:42 PM   #14
Jeeper
 
H8_MUD's Avatar
 
Join Date: Jun 2013
Location: NJ
Posts: 228
Quote:
Originally Posted by NU2DAWAVE View Post
Ok now a late update the reason I asked or put up this post: we wife and I had trusted on our sales person and judgements on what to put on our Jeep with understanding of loss of MPG and so forth but when we got our JK back it broke down. The rear differential felt like something when loose and started to whine, on my way to a fishing trip two hours into the drive I had to turn back and take it back to the shop. After a week of waiting we got it back on a Thursday so I drove it to work on Friday same thing happened so here we go again back to the shop a week later my wife picks it up by the time I get home she tells me it's making a loud noise. So I get in and it sounded like a freight train right outer bearing went out also busted left outer seal of axle. Now they tow it back to the shop for another week, we have it now and everything is fine except that I have a seepage on top of the differential (front). I believe they made a hole for the air locker then decided to relocate the hole where it is now anyhow were happy to have our Jeep back and everything is fine except the leak lol so that is why I made this post thinking we were at fault
You have to get the leakage fixed ASAP. Its time to go to a different shop or learn how to fix it yourself.
H8_MUD is offline   Quote Quick Reply
Old 08-18-2013, 02:52 PM   #15
Jeeper
 
Lowerumble's Avatar
 
Join Date: Jun 2012
Posts: 2,000
Quote:
Originally Posted by Gunner View Post
Stick or Auto and what year are you driving?
^This
Lowerumble is offline   Quote Quick Reply
Old 08-18-2013, 04:59 PM   #16
Jeeper
 
NU2DAWAVE's Avatar
 
Join Date: May 2013
Posts: 53
My Jk is a 2008 JKU four door automatic transmission, I always do the work of my vehicles but of course my wife talked me into them doing the work instead of me. I had a four day holiday coming and I was going to do the work, but like I said the wife said let them do the work and those four days you could go fishing. So that's why I didn't do the work. We bought
Airaid intake
3.5 Rubicon Express Super Flex lift
Front and back ABR Air Lockers with compressor
G2 4:88 gears
Tires and wheels
Superchip

Ok, the leak for now I applied JB Weld on it and seems to be working for now but I do want to spot weld the crack but afraid to make it worse how does any one fix a cracked pumpkin
NU2DAWAVE is offline   Quote Quick Reply
Old 08-18-2013, 06:07 PM   #17
Jeeper
 
H8_MUD's Avatar
 
Join Date: Jun 2013
Location: NJ
Posts: 228
Quote:
Originally Posted by NU2DAWAVE View Post
...I always do the work of my vehicles..
That's great! Many years ago I took my Harley to the dealer for something simple and they screwed up the entire job. From that day on I swore I would never take my bike back to a stealership, bought the service manual and learned to do everything myself. Jeep stealership are no different.
H8_MUD is offline   Quote Quick Reply
Old 08-18-2013, 06:17 PM   #18
Jeeper
 
sinbob's Avatar
 
Join Date: Nov 2012
Location: Fresno Ca
Posts: 728
Quote:
Originally Posted by tluke View Post
I have a 2013 with 35's and the 6 speed manual. I went with 4.88's because the 4.56's were not available at the time. It's fine around town but on the highway at 70mph I am turning 3000rpm. 65 mph seems more comforable for long hauls. That drops the rpm closer to 2600 rpm. 1st gear is a bit low on the street so sometimes I start out in 2nd. Other than that no real regrets. I used the Procal and it worked like a charm.
I have an 06 with the same setup and yes 65 runs around 2600 rpm and start out in 2nd gear 2.26 as 1st is to low at 4.46

I have taken mine up to 95 one time just to see how she would handle. It is not a BMW but she does ok
__________________
It's not about getting out of the Storm, but learning to dance in the rain.
When I die I am going to be buried with my Jeep, cause I haven't yet found a hole it can't get out of!!!!!
06 TJ Rubi 4.0 and alot of other crap
sinbob is offline   Quote Quick Reply
Old 08-18-2013, 06:28 PM   #19
Race Car Dave

WF Supporting Member
 
NFRs2000NYC's Avatar
 
Join Date: Nov 2011
Location: NYC
Posts: 6,942
Quote:
Originally Posted by damndirtydog View Post
A jeep that can go 100mph?! I'll believe it when I see it.
Jeeps have a fail safe mechanisim so a situation like that would never happen, it's called a non aerodynamic refrigerator box body style and a V6 engine.
The one time I hit 85 mph in mine I had to seek help for post traumatic stress syndrome, it was real scarey.
Probably would even worry about that silly stuff New2dawave.
I hit 97 on the i70 just outside Moab. Long, downhill, and empty. Didn't feel like the rig was about to flip, but I agree, probably not the best thing to do, especially if you are gonna need to stop.
NFRs2000NYC is offline   Quote Quick Reply
Old 08-18-2013, 07:09 PM   #20
Jeeper
 
flipmeover's Avatar
 
Join Date: Mar 2013
Location: Orlando, FL
Posts: 219
Quote:
Originally Posted by mckey73 View Post
113 mph in a '12 JKU with 3.73's and a manual @ 6,000 ft. I think it woulda done better with 4.10's, as I was having trouble in both 4th and 5th. That's alot of wind to push!
Holy crap! Did you go back in time? I'm pretty sure at that speed with Jeep aerodynamics, the flux capacitor is not required...

__________________
Normal people believe that if it ain't broke, don't fix it. Engineers believe that if it ain't broke, it doesn't have enough features yet.
- Scott Adams
flipmeover 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:
If you do not want to register, fill this field only and the name will be used as user name for your post.
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




» Featured Product

All times are GMT -5. The time now is 09:42 AM.



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