Usamedic Posted September 23, 2012 Share Posted September 23, 2012 Got me a 1987 mj with the 4.0. Thinking of buying a stroker, or getting my engine built locally. Looks like I may have a complete spare truck as well. Anyway, should I go for a different auto tranny and newer tcase right from the get go? Thinking about the issues with 21 spline tcase input on the 87 tcase with the aw4 tranny, and the reliability in general of the stock trans. What transmission should I go with? Sorry but the search function just is not working tonight on the forum Link to comment Share on other sites More sharing options...
Geonovast Posted September 23, 2012 Share Posted September 23, 2012 The AW-4 should be able to handle a stroker just fine. You drivetrain concern should be with your rear axle. I've been on this forum for over 5 years, and I haven't seen a single post about someone snapping a 21 spline trans output shaft/ t-case input. Link to comment Share on other sites More sharing options...
Incommando Posted September 23, 2012 Share Posted September 23, 2012 The other issue is the Renix. It may be cheaper in the long run to buy a complete OBD 4.0/AW4/231 junk rig to get all of the wiring and all. I ran & 'wheeled my '88 with that same 21-spline tranny and didn't hurt it. Link to comment Share on other sites More sharing options...
mvusse Posted September 23, 2012 Share Posted September 23, 2012 I have an 87 MJ with the Renix 4.0, AW4 transmission with the 21 spline output and 35" tires on locked axles. Been told I wheel my truck harder than most, but have never had an issue with the transmission or transfer case. For that measure, never had an issue with the 4.0 either, and I like the simplicity of the Renix electronics. From my experience way more reliable than the Chrysler system used on the HO engines. Link to comment Share on other sites More sharing options...
Usamedic Posted September 25, 2012 Author Share Posted September 25, 2012 Thanks for the replies! I am sticking with the renix, and apparently the tranny issues I heard about were all regarding the manual trannys. Got a complete spare truck too! I just have to go get it. Gonna build it as is. Now I just have to sell this 2006 rubicon unlimited and I can start in on it Link to comment Share on other sites More sharing options...
Usamedic Posted February 4, 2013 Author Share Posted February 4, 2013 Geo, my rear is a Dana 44 so no concerns there. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now