Shops for re-gearing in Raleigh/Durham area?
07-08-2015 | 02:37 PM
#11
Thread Starter
JK Newbie
Joined: Jun 2015
Posts: 28
Likes: 0
From: Hillsborough, NC
Thanks again to all who recommended East Coast Gear Supply. Talked to them today, explained what I'll be using the Jeep for (Hwy drives to Coast, then running on the beach, occasional trip to Uwharrie Ntl Forest, etc), and they recommended going to 5.13 Yukon gearing. So I'm dropping it off Monday for gear swap, C-Gussets, full Ball Joints, and an AEV ProCal to keep the computer from freaking out 
. Can't wait to get it back Tues/Weds and see how it goes. Everything I've seen tells me it's going to drive like a completely different vehicle - hard not to moving away from the 3.21s...I'll share my impressions once everything gets broken in.
. Can't wait to get it back Tues/Weds and see how it goes. Everything I've seen tells me it's going to drive like a completely different vehicle - hard not to moving away from the 3.21s...I'll share my impressions once everything gets broken in.
07-08-2015 | 05:11 PM
#13
JK Jedi Master
Joined: Jan 2008
Posts: 11,463
Likes: 162
From: Austin <--> Colorado Springs
With a 3.8 and a 6-spd, and assuming your 35's measure out to 34" :
5.13 = 2982 rpm @ 70 mph
4.88 = 2837 rpm @ 70 mph
5.13's are popular for 3.8 auto's with 35's. 4.88's or 4.56's seem to be more popular with the 3.8 6-spd folks.
My 35's measured 33.5", which isn't all that uncommon. Shorter tires means higher rpm's.
Anyway, just food for thought to see if we can get your head to explode...
Last edited by nthinuf; 07-08-2015 at 05:13 PM.
07-08-2015 | 05:30 PM
#14
Thread Starter
JK Newbie
Joined: Jun 2015
Posts: 28
Likes: 0
From: Hillsborough, NC
You might be better off using the JK specific charts. They break it down by 'JK' engine and 'JK' transmission. (search on something like "jeep jk rpm chart", if you pull up the right ones, you will see the breakdown for engine and transmission)
With a 3.8 and a 6-spd, and assuming your 35's measure out to 34" :
5.13 = 2982 rpm @ 70 mph
4.88 = 2837 rpm @ 70 mph
5.13's are popular for 3.8 auto's with 35's. 4.88's or 4.56's seem to be more popular with the 3.8 6-spd folks.
My 35's measured 33.5", which isn't all that uncommon. Shorter tires means higher rpm's.
Anyway, just food for thought to see if we can get your head to explode...
With a 3.8 and a 6-spd, and assuming your 35's measure out to 34" :
5.13 = 2982 rpm @ 70 mph
4.88 = 2837 rpm @ 70 mph
5.13's are popular for 3.8 auto's with 35's. 4.88's or 4.56's seem to be more popular with the 3.8 6-spd folks.
My 35's measured 33.5", which isn't all that uncommon. Shorter tires means higher rpm's.
Anyway, just food for thought to see if we can get your head to explode...
Thanks - chose to skip tables, etc, as my head was indeed going to explode
and consulted with the "experts" at ECGS - gave them my vehicle specs and desired usage, and they said 4.88s are an option, but would recommend the 5.13s as they would get me where i want to go at the same cost. Guess in anticipation of future larger tires, having 5.13s would accommodate 37s, and while running "35s", will only add ~150 RPM to the engine which isn't too bad or taxing. Not sure i'll ever go to 37s, just hoping for the best - as anything will be better than the 3.21s.....
08-05-2015 | 01:18 PM
#15
JK Jedi
Joined: May 2011
Posts: 4,343
Likes: 1
From: Wake Forest, NC
Can you provide feedback on your satisfaction with the service and pricing you received from ECGS? I just called 4WPs and they want around $1,200 - $1,300 to do an install and I already have the ring and pinions and master rebuild kits.