40" with 4:88 ? - JKowners.com : Jeep Wrangler JK Forum
 
LinkBack Thread Tools Display Modes
post #1 of 13 Old 07-08-2015, 04:30 PM Thread Starter
Wheeler
 
Join Date: Apr 2015
Age: 51
Posts: 32
Feedback: 0 reviews
40" with 4:88 ?

How do you all think this would be? Touch too low but livable?

on 37" now at about 2500 rpm at 67 mph figure real tire will be 38.5-39" drop 200 rpm?

2014 JKU
For a daily driver 25 min of freeway each way
trail duty on weekends with a rubicon transfer case
already have hydro assist and rock jock 60s.
dave22 is offline  
Sponsored Links
Advertisement
 
post #2 of 13 Old 07-08-2015, 04:53 PM
The Wheelin Man's Friend
 
RiverCityOffroad's Avatar
 
Join Date: Aug 2010
Location: Austin, TX
Posts: 8,649
Garage
Feedback: 60 reviews

It won't be horrible. Go for it!


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
RiverCityOffroad is offline  
post #3 of 13 Old 07-08-2015, 05:40 PM
JKowners Vendor
 
Join Date: Nov 2007
Location: Wellington Nv.
Posts: 1,144
Feedback: 2 reviews

5.38 and 40" works great if its a heavy 4 door.

Good calculator:
http://www.grimmjeeper.com/gears.html

Dealer for: MoTech, Atlas, Dynatrac, Rock Krawler, ORO, Currie, Poison Spyder, Bilstein, Fox, SWAY-A-WAY, Ridid, Adams and Tom Woods DS's. And much more!


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
CT Performance, Inc is offline  
Sponsored Links
Advertisement
 
post #4 of 13 Old 07-08-2015, 07:26 PM
Granite Guru
 
RkyMtnJK's Avatar
 
Join Date: Mar 2014
Location: Woodland Park, CO
Posts: 205
Feedback: 1 reviews

manual or auto?

I have 5.38s and 40s with an auto and a 3.8...wouldnt want to be any less geared at all! Mine is a 4 door with a matching spare and armor/skids/etc and the jeep lives between 7500' and 11000' of elevation at all times, all of which suck away the power pretty quick!.
RkyMtnJK is offline  
post #5 of 13 Old 07-08-2015, 07:48 PM Thread Starter
Wheeler
 
Join Date: Apr 2015
Age: 51
Posts: 32
Feedback: 0 reviews

It's the 3.6 auto pretty light got the BFH bumpers and a 45 lb rock winch, synthetic
Does have some heavy sliders though

Ok this Sat I'll throw them on and report back, suppose I'll have it regeared if I need to not the end of the world.
dave22 is offline  
post #6 of 13 Old 07-08-2015, 08:05 PM
Rock God
 
Join Date: Sep 2010
Posts: 857
Feedback: 0 reviews


MISHIMOTO IS JUNK
chknkatsu is offline  
post #7 of 13 Old 07-08-2015, 08:09 PM Thread Starter
Wheeler
 
Join Date: Apr 2015
Age: 51
Posts: 32
Feedback: 0 reviews

Oh sorry for bringing up a topic that has been discussed before
Obviously some here just get their vagina all sandy when that happens.
My apologies.
dave22 is offline  
post #8 of 13 Old 07-12-2015, 09:01 AM Thread Starter
Wheeler
 
Join Date: Apr 2015
Age: 51
Posts: 32
Feedback: 0 reviews

They went on yesterday gearing is good for a daily driver very nice on the highway have not had it off road yet. I will have to trim up some sheet metal on the rear of the front fender as it looks like it will eat the tire when it stuffs.

...that and my jack is now worthless will have to build an extension or figure something else out.
dave22 is offline  
post #9 of 13 Old 07-13-2015, 03:15 AM
Granite Guru
 
Join Date: Oct 2012
Age: 33
Posts: 138
Feedback: 0 reviews

I have a 2012 6 speed with 4.88s and 40x13.50r17s. I have zero issues on road and off. I can still start off in 2nd gear from a stop light with zero issues.
CraigP is offline  
post #10 of 13 Old 07-13-2015, 04:23 AM
Rock God
 
bgall's Avatar
 
Join Date: Feb 2012
Posts: 1,272
Feedback: 0 reviews

My 2012 3.6 auto does great with 40s and 4.88s (d60s) but when I hit hills it struggles to keep gear and usually has to downshift. I notice the lack of power when the roads are not flat. Offroad it has been no issue due to the 4:1 tcase in my rubi. I actually get 15.2-16.1 mpg in town. If I had it to do over, I would have gone 5.13s.

I have jeeps. I do shit to them.
bgall is offline  
post #11 of 13 Old 07-13-2015, 07:12 AM Thread Starter
Wheeler
 
Join Date: Apr 2015
Age: 51
Posts: 32
Feedback: 0 reviews

gotta agree with that went 4 wheeling yesterday and no issues when the rubi t case is involved but getting there I noticed tranny staying in 4th, the OD never engages even on gentle inclines going 70 mph. Thats pretty annoying.

5.13 are going in soon as I'm back from vacation.

Also stuffed the rear tire into my wheel well sheet metal, will have to add about 3" to the rear bump stop pad.
dave22 is offline  
post #12 of 13 Old 07-13-2015, 07:19 AM
Granite Guru
 
Bacon's Avatar
 
Join Date: May 2013
Location: Canada, Eh
Posts: 163
Feedback: 0 reviews

Do you have a tuner to recalibrate for the bigger tires? It should help the shift points.

08 JKUR

Just an asshole with a Jeep....

Rancho+AEV+Rubicon Express+Rock Krawler+Synergy+Warn,+Rough Country+Cobra+Banks+Magnaflow+Superchips+Bestop+Po ison Spyder+EVO+G2+Mopar+Yukon+WTO+Level 8+Coopers+garage wontons
Bacon is offline  
post #13 of 13 Old 07-14-2015, 06:19 AM Thread Starter
Wheeler
 
Join Date: Apr 2015
Age: 51
Posts: 32
Feedback: 0 reviews

Yep took care of that. Would still be more pleasant to drive with a re gear.

Or add 300 HP one or the other
dave22 is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JKowners.com : Jeep Wrangler JK 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:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



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 On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome