YJ trans issues - JeepForum.com
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 > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > YJ trans issues

D.i.y. Ford 8.8 tj,xj,yjSavvy Aluminum BumpersSwag Off Road BIG-HIT TJ-YJ Rear Bumper

Unread 09-16-2010, 12:17 PM   #1
Registered User
1995 XJ Cherokee 
Join Date: Aug 2007
Location: Connecticut
Posts: 804
YJ trans issues

Hokay, im an XJ guy, but a friend of mine got a yj. Its a 90 2.5, 5spd(ax-5??) 231. The trans wont go into 1st gear unless you double clutch it, presuming its in not so good shape cause the PO left it in a swamp for a week, what would a be a good trans to bolt in? AX-15?? AW4?? he would preffer something bolt in but strong.

Are Ax5s really weak? ive heard they are.

bigbike is offline   Reply With Quote
Unread 09-16-2010, 12:33 PM   #2
Uncle Paul has spoken...
paultyler's Avatar
1992 YJ Wrangler 
Join Date: Feb 2005
Location: California
Posts: 2,537
Yes they are lightweight. They become an issue when you get larger tires. The issue arises not off road but on the highway. When geared down in 4low they rarely break because there is less stress on them in these situations.

The problems arise when you on underpowered on the highway and roll around with the pedal floored to get your speed up. That's when they usually develop problems. Often what goes is just the 5th gear as it is held on by a snap ring that can pop off....as I am experiencing right now.

As for replacements nothing will simply bolt in. If you get an AX15, which is probably the best option you will need to get a new bellhousing. Plus the shaft on an AX5 is 21 splines and an AX15 is 23 I think. Therefore some modification will be required. Also, your driveshafts may need to be shortened or lengthened. It turns into a modestly expensive job when you consider you can get a used AX5 for $250-$400 and rebuilt one for $750.

This is a dilemma I have faced for years. I have gone through 4 AX5s but each time I simply replaced it.
My Jeep - Video

My Jeep in the Snow

92 YJ, 35' MTR Kevlars, Klune/Dana 20, 4.88s, SYE, Rubicon D44s w/Rubicon lockers, front and rear Alloy USA chromoly shafts with 30 spline outers, JK electric swaybar, T&T tube fenders, custom cv driveshafts, RE 4.5 XD springs, M.O.R.E. 5/8'' boomerang shackles + 2' BL, 15lb Powertank, 4.0L TB & TB spacer, ARB Snorkel, K&N filter, rear bumper and tire rack, Rancho 9000s, AtoZ Rockers, Skid-Row Engine skid plate, Teraflex Bellyup, JCR Offroad 1 Ton TieRod, rock lights, RE hand throttle, M.O.R.E. roll cage, corners, 9000lb winch with synthetic cable in-cab winch controller (12voltguy.com), Dual Blue Top Optimas with 12voltguy dual battery controller, a/c (ackits.com)

Originally Posted by joshrad View Post
This Uncle Paul guy seems to know what he's talking about.
paultyler is offline   Reply With Quote
Unread 09-16-2010, 12:44 PM   #3
Registered User
1995 YJ Wrangler 
Join Date: Feb 2009
Location: Wilmington
Posts: 957
if you can find a dodge dakota with the 2.5l you can take out the entire power and drivetrain. the dakota 2.5l came backed with an AX15 with the necessary bellhousing for adaptation. othersie you can get an ax15 and buy the bellhousing online new (not too pricey forgot site also (or go to dealer)).
CreepyCrawler95 is offline   Reply With Quote
Unread 09-16-2010, 03:55 PM   #4
Registered User
1993 YJ Wrangler 
Join Date: Aug 2009
Location: Oregon Coast, Oregon
Posts: 1,471
are the 2.5 ax15s better geared than the jeep 4.0 ax15s? I never liked the idea of putting the ax15 on a 2.5 becuase the gears are even higher than the ax5
imstillatwork is offline   Reply With Quote
Unread 09-16-2010, 05:48 PM   #5
Registered User
1991 YJ Wrangler 
Join Date: Mar 2006
Posts: 9
I may be having a problem with my 1991 4.0. Not sure which transmission I have. Are they all the same for the 2.5 4-Cyl. and the 4.0 HO?
mikeys91 is offline   Reply With Quote
Unread 09-16-2010, 09:54 PM   #6
Registered User
1995 YJ Wrangler 
Join Date: Feb 2009
Location: Wilmington
Posts: 957
there is little difference in the gearing of the 2 trannies. since hes running a 4banger hes already got decent (stock) gears...unless youve geared lower. what size tire is your buddy running?
CreepyCrawler95 is offline   Reply With Quote
Unread 09-16-2010, 10:43 PM   #7
Registered User
1995 YJ Wrangler 
Join Date: Feb 2009
Location: Wilmington
Posts: 957
no the 2.5 is backed by the ax5 and the 4.0 is backed with the ax15 for all manual yj models.the BA-10 came behind the 258 I6 i believe only other tranny i know of behind the 4.0 is the nv3550 in tj models...idk about jks
CreepyCrawler95 is offline   Reply With Quote
Thread Tools

Suggested Threads

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.