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Old 10-17-2012, 01:16 PM   #1
Join Date: May 2012
Location: Ferndale, WA
Posts: 9
trans swap question

I have a 88 4.2l Having the engine rebuilt because it was spewing oil everywhere. While that is being done we decided to have the trans checked out. Trans shop says we have a peugeot trans that is garbage, can't get parts etc. They tell us we need to get an AX 15. Fine, but then they tell us they're having a hard time finding us the right one, that it has to be from a 4.2l or it's a lot of work to swap, I think they've found one but it's $900 I think... I've found a couple that were from a 4.0l that were reasonably priced, $350-500.
I just want to make sure that we're not taken advantage on this because we brought it in to get it repaired.
Thanks for any advice!

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Old 10-17-2012, 01:34 PM   #2
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personally, I say leave it in the jeep and start hunting for an AX15. Why replace it if its not broke? Yeah, maybe its a harder breed to work on but shoot, at least run it until it dies. Just 'cause the engines out doesn't meen its all that easier to change the trans. Especially at a shop. Maybe if your using a block & tackle pully out in the backyard from a tree it might be easier to just pull it once but heck, in a shop you can pull a tranny out the bottom and not even move the engine. You'd actually support the rear of the engine so it doesn't move.

I dont know for sure if a 4.2 and a 4.0 are the same rear trans bolt pattern but if they are different you'd think it would only be the bell housing that is different. Those can be replaced, Not sure though...

just my opinion...

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Old 10-17-2012, 01:43 PM   #3
Join Date: May 2012
Location: Ferndale, WA
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Guess I should've mentioned...I was starting to have problems shifting, it was starting to get to jam it into gear until it warmed up.
As far as I know, the bell housing is different.
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Old 10-17-2012, 01:43 PM   #4
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You do NOT need one from a 4.2 motor. Any jeep AX-15 will work fine, tho you might have to juggle some things like pilot bushing size & clutch slave cylinder parts.

Your best/easiest bet is to get the entire bellhousing/tranny/T-case from a 90-92 those years involve the least work to convert (they are a virtual bolt-in swap).

There are plenty of write ups on this swap....I suggest reading a bunch & printing one out to take in to your mechanic.

BTW, be sure to use a clutch for the 4.2 flywheel...NOT one for a 4.0/AX-15.

I did the same swap for under 500, total.

FYI ~ the back of the bellhousing pattern is different from your current set up. As is the input shaft to the T-case, and the speedo drive on later YJs w/ the AX-15. (these are the main reasons why the years mention offer the least hassle)
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Old 10-17-2012, 01:58 PM   #5
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Old 10-18-2012, 05:30 PM   #6
Join Date: May 2012
Location: Ferndale, WA
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Just wanted to thank you all for your advice.
Engine rebuild is done...just have to wait for the trans. to be done now.
Trans shop has located one and is now negotiating $$. Hopefully it will be done soon, I just want to be able to drive it again.

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