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chad085 01-30-2010 11:12 AM

trans swap please help!!!
started a transmission swap yesterday and hit a major roadblock!!! the plan was to swap my 3 speed auto for an ax-15 from another yj. Both jeeps are 1994, both 4.0 inline 6 cyl. Both jeeps run drive and shift great, and the idea was to swap transmissions completely in both jeeps. after a few hours of teardown we were horrified to discover that the crankshafts are different???? mine has a deeper, larger center section that the torque converter slid in to, which will not accept a stock pilot bushing. And the crank on the manual trans motor is shallower, which does not allow the torque converter to sit flush against the flexplate and be bolted down properly???? what gives???? why would there be 2 different cranks in jeep motors of the same year??? anyone else ever had this problem?? please help!!! 2 jeeps in pieces and nobody's happy!!!

4Jeepn 01-30-2010 11:14 AM

auto vs manual trans. Call advance adaptors or novak they may be able to help ya.

Ray - San Jose 01-30-2010 11:27 AM

It's been awhile since I pulled auto and manual transmissions, but if I recall correctly there's a pilot bushing (usually bronze) installed in the back of the crank shaft for the manual transmission that shaft to fit into. You can get it out on the cheap by packing it with grease and whittling down a broom handle to fit snugly in it. Driving the handle in increases the pressure of the grease and presses the bushing out. You'll want to install a new bushing into the engine that's receiving the manual trans.

chad085 01-30-2010 11:40 AM

ive got a whole new clutch kit for installing the manual trans into my jeep. the problem is, the hole in the crank where the pilot bushing resides is too big!! the crank appears to be totally different on the automatic motor than it is on the manual motor. i guess jeep didnt want to make things interchangeable. i will try calling AA. thanks

czjeeper 01-30-2010 11:56 AM

On mine, the bushing was in the flywheel, not the crank.

ks90yj 01-30-2010 12:16 PM

I did the same thing Advanced adapters has what you need kind of call them and tell them what you are doing and they will hook you up. Although once you get the brass bushing you will have to sand it down on the out side or lathe it down. I took mine to a local shop and they were able to do it for me.

ks90yj 01-30-2010 12:19 PM

This is how I did mine I did manual to manual though. It should be about the same though I think

This is for all of you who are thinking about doing this swap. Its overall pretty easy (as long as you have the right parts) First things first get you a new can of PB cause you'll need it! Get you some little zip lock bags and a marker and be sure to label what parts you put in what bag. Next youll need to get an inverted torx bit its a m12. This is for the top two bellhousing bolts pain in the arss (I replaced them with regular bolts) Here is the most important one PIOLET BEARING!!!! before you even start call advanced adapters and have them send you the one for you tranny. Measure your AX15 inputshaft and it should be .75 or I forget what the other measurement was but measure it anywho. When you get it, it will be to big to fit in the back of your crank, so you can do two things either put it on a drill bit and grab some sand paper and start sanding yet another pain or (the method I tried after sanding) take it down to your local machine shop and have them get it the size you need (I took the piolet bearing from my new clutch kit and they sized it up). Next get a new clutch well worth it. My next recomendation is find you an external slave cylinder. I stuck with the internal but kind of regret it now. After haveing to pull the tranny back out after having it all bolted up and finding out it leaks like crazy if you dont put the o-rings in the lines :banghead:. So go with the external slave. If you do that I believe you need to swap your master cylinder. Next get you a little hand pump for your t-case if you dont have one. Made filling way easier!! And last but not least have some good help around makes a hell of a difference!!!
Hit me up if you have any questions!:D:D

chad085 01-31-2010 10:37 AM

ks90yj, what year jeep did you do this on?? a 1990? (guessing from your screen name....) and what year was the original trans, and the replacement trans?? It seems as though the engine in my jeep has been rebuilt during its 134,000 mile lifespan. what im wondering is if a crank from a '91 or older jeep was used in the rebuild, since the pre '91 ax15 had a different size input shaft. although the current automatic tranny is supposedly original to the jeep, but has also been rebuilt. Ahhhhh, the joys of buying a used vehicle!!! suprise at every corner!!!! LOL

ks90yj 01-31-2010 11:34 AM

Are you sure the pre 91' trany was an ax15 because the ba10-5 that I had looked pretty similar to the ax-15 I put in. Im not sure though. Your best bet would be to call advanced adapters after you measure your crank and all that goodness and they should be able to hook you up with what ever you need.

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