3 speed auto, 5.29's and 37's - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > General Technical Discussions > Engines & Drivetrain > 3 speed auto, 5.29's and 37's

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineToxic Brakes - 3000 PSI Braided Stainless Steel Brake LineCess Recovery Gear Snatch Tow Strap OffRoad @ ROCKRIDGE4WD

Reply
Unread 10-09-2012, 08:17 AM   #1
D-13
Registered User
1997 TJ Wrangler 
 
Join Date: Dec 2010
Location: Las Cruces, NM
Posts: 54
3 speed auto, 5.29's and 37's

Did a search last night but nothing really came up. Most of rhe info was manual tranny. Who is running kevlor 37's with 5.29 or 5.38 wih a 3 speed auto? Trying to see what they think of it? Rpms and how it does on higher speeds. Also how safe is it to be in the higher rpms? i have 4.88 and just dosent seem like it has that get up and go. Im running currie hi p-9 and its either 4.88 or 5.29's. 5.13's would of been nice but no go with currie. Thanks for the input.


David

D-13 is offline   Reply With Quote
Unread 10-09-2012, 08:35 AM   #2
Imped
Web Wheeler
 
Imped's Avatar
2004 TJ Wrangler 
 
Join Date: Feb 2008
Location: Indianapolis
Posts: 19,221
With 4.88's now, you're at about 2900 RPM @ 65mph. With 5.29 gears, you'll be at about 3100. You can easily determine this using any one of the many gear/tire charts available online or simply using what you know:

5.29-4.88 = .41
.41/4.88 = .084 or 8.4%
2900 x 1.084 = 3144 RPM

I'd stick with 4.88's. If you want a slower crawl speed, address the t-case. If you want a peppier Jeep, you'll have to ditch that lethargic 32rh. Your best bet is swapping in an AW4....the OD will allow you to run lower diff gearing (like 5.29 or 5.38) while spinning nice RPM's on the highway, you'll gain a slower crawl speed, and that auto isn't a power-robbing slushbox.
__________________
OlllllllO
Float Test Build
IndyORV
Imped is offline   Reply With Quote
Unread 10-09-2012, 02:01 PM   #3
D-13
Registered User
1997 TJ Wrangler 
 
Join Date: Dec 2010
Location: Las Cruces, NM
Posts: 54
The was the plan, the aw4 I found fell threw. When I bought the front it had 5.29's in it. The rear had 4.88's, I figured I could swap to a aw4 now that my 32rh blew but I'm getting it rebuilt for a run in 2 weeks then sell it when I find a low mile aw4. If any one has on pm please. Hate the way the jeep runs withs the 4.88's. Thanks for the heads up my man!
D-13 is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.