Swapping out a BA10 for an AX15?

[boomer1]

I have a previous posting about by son's clutch and transmission dying on his 1988 cherokee.

Here's the question - one of the replies suggested that since it looks like we are going to have to drop the tranny to replase the internal slave and most likely the rest of the clutch, he might want to think about swapping in an AX15, since the BA10's are notorious for failing.

Right now, besides the clutch being out, the shift lever will move back and forth in netural, but will not go into any gear. From what I've been told, the shifting forks are out of line and if we pull the console and open up the top of the tranny, we can re-aline the forks and get the shifting problem fixed.

I found an AX15 out of a 1997 TJ for $100. But I was wondering if anyone has done this swap into a 1988 cherokee. I know the slave is external on the AX15, which would be a good thing, but have no idea if we are going to need a new bell housing, if the transfer case will swap over or what else we are going to run into. One of the responses stated that it's an "easy" swap, but just wondering if anyone else has done this and just how easy it really is.

Sorry for my stupidity, any help would be appreciated.

Thanks

 

[YELLAHEEP]

Stay away from any transmission from a Wrangler (YJ,TJ). The tail end is clocked differently putting the t-case up higher than the XJ....... the XJ floor pans won't accept higher t-case clocking without cutting and modifying the floor pan under the driver's seat.

There are a few parts you need for compatibility when swapping from the BA to the AX. A specific part numbered pilot bearing that I believe comes from something other than an XJ; carrying over the newer clutch master cylinder and pressure line from the donor XJ as there are differences between the two transmissions in how the inner slave cylinders connect to the pressure line.

Shifters are different so be sure to get the shifter with the donor AX15. I believe there may be some difference in the transmission mount as well.

The things the BA and AX DO share in common are: the bell housing bolt pattern; The flywheel is specific to the engine so in your case, keep the original fly wheel - IIRC, the teeth on the outside that send the pulse to the CPS are different for the Renix system than the OBDI and OBDII. And the overall length of the transmissions are the same - no need to get different drive shafts.

 

[boomer1]

Yella

Sounds like the swap with the TJ AX15 is more complicated, and would be over our heads.

But now we have another option. I have an offer of a complete driveline (AX15 tranny, bell housing, and transfer case) from a 1990 XJ.

The jeep is a friends parts jeep and he said he drove it home and the tranny seemed good at the time.

He told me we could come over and take the entire set up out at no charge.

I'm assuming that the best thing to do would be to pull everthing including the bell housing, tranny and transfer.

Would this be more or less a bolt up to the 1988? Sounds like we would have to find out which pilot bearing we would need, but the master cylinder and lines might be the same, and maybe have the same shifter linkage.

It also sounds line the bell housing bolt pattern and fly wheel would be the same, but how about any CPS issues between the 1988 and 1990?

I'm also assuming that we would then need to buy a clutch package for a 1990, since the slave is external?

Thanks

 

[YELLAHEEP]

According to the Novak website:

http://www.novak-adapt.com/knowledge/ax15.htm

"1988 to 1991 AX15 input shafts have a smaller (~19/32") pilot tip. 1992-1999 AX15's have a larger (~3/4") pilot tip."


So it would appear that the AX15 from the '90 would be a direct bolt in to your '88........ :thumbup:

 

[Stang5lgt]

Yes I have alot experience with AX15 I have sold like 10 of them on Ebay. When they went to the HO motor in 91 they changed the crank and input shaft on the AX15. So the 90 donor you have will be prefect. I ran into this problem when I swapped a 94 HO motor into my 89 Renix. The pilot bearing for HO has smaller diameter outside where it presses into the crank and larger hole in the center. So I had to take older style renix pilot bearing and machine it down until it would fit crank. It was fun.

As far as TJ transmission it will work you just have to redrill the rear flange to clock the transfer case. Pretty easy if you know the measurement.

 

[Frank Z]

Yes I have alot experience with AX15 I have sold like 10 of them on Ebay. When they went to the HO motor in 91 they changed the crank and input shaft on the AX15. So the 90 donor you have will be prefect. I ran into this problem when I swapped a 94 HO motor into my 89 Renix. The pilot bearing for HO has smaller diameter outside where it presses into the crank and larger hole in the center. So I had to take older style renix pilot bearing and machine it down until it would fit crank. It was fun.

As far as TJ transmission it will work you just have to redrill the rear flange to clock the transfer case. Pretty easy if you know the measurement.

Actually you don't need the measurement at all. A GM Gasket #24245110 matches the bolt pattern on the NP231J and it cost all of $10. Simply match the bolt pattern (there's only 1 correct pattern) and then clock the gasket, mark the new hole locations and drill. The casting for the transfercase is cast with enough room so strength won't be a concern.

 

[Stang5lgt]

Actually you don't need the measurement at all. A GM Gasket #24245110 matches the bolt pattern on the NP231J and it cost all of $10. Simply match the bolt pattern (there's only 1 correct pattern) and then clock the gasket, mark the new hole locations and drill. The casting for the transfercase is cast with enough room so strength won't be a concern.

There ya go I knew there had to be a easier way to do. :thumbup:

 

[boomer1]

Thanks everyone

Here's the plan - from what I'm finding out, it looks like the AX15 bell housing, tranny, transfer case and cross member out of the 1990 will be a direct bolt in to my son's 1988 to replace the BA10. Sounds like that would be a good up grade while we are replacing the clutch and leaking slave cylinder and eliminate the question/problem with the BA10.

The only question that I haven't found out about is any CPS issues with the swap, I'm assuming it shouldn't be a problem and will probably be ok.

So we plan on pulling everything off the parts jeep on Saturday Sept. 5th. Getting it home and cleaned up. We will then pick up the clutch package, so we hopefully have all the parts we need.

After we to that, we will probably be looking at swapping it all out on Saturday the 12th and hopefully have it back running that weekend. I post again after we get everything together and see if any one is available to help.

Again, thanks for everyone's help. Everyone has been great - what started out as a fix that was over our head, looks like is actually doable and will be a learning experience.