1989 5 speed Manual Slave Cylinder three in three years

[gai092460]

Hello Jeep  Comanche Family 

 

I am baffled with challenge of replacing my Slave cylinder 3 times in 3 years ( Using LUK parts ) any suggestions ? Other threads I read 

 

suggest later model trans ,prefer not go that route ,there must be a better choice 

 

Kind Regards 

 

George 

[eaglescout526]

Welllll parts like that have gone to complete crap. Sometimes you can end up with a good one that will last, most they will be crap. You could always go to an external slave set up which requires changing the bell house and the master I think if you have a 4.0L. Well even the 2.5L ended up using the same set up later on. 

 

Yeah engine info goes a long way to helping you out better.

[89 MJ]

Echoing above, which engine and trans do you have?

 

If you’ve got the Peugeot, there’s not much you can do about it, other than put another slave cylinder in it. 
If you’ve got an AX5 or AX15, swapping to an external slave cylinder would be the way to go. 

[Eagle_SX4]

I had the same issue. I switched to a later master cylinder (91-96). It is fully aluminum including the reservoir. The AX15 used the same master cylinder for both internal and external slave cylinders. External slave AX15 came out some time in 93. There are 2 issues you will need to address. 1, the newer master cylinder uses a different fitting. 2, the rod that attaches to the pedal will need to be drilled out a slightly larger diameter.

 

I haven't had to replace my master cylinder going on 1.5 years now.

[87MJTIM]

Mine came with the BA10/5.  It went through 5 slave cylinders before I swapped out to an AX15 with an external slave cylinder.

 

Like Eagle and 89 MJ asked - what engine is in your MJ?

 

4.0: 89 was a mixed year.  The Peugeot BA10 was the trans for the first portion of production.  Jeep switched to the AX15 with the internal slave cyl. for the second half of the model year.  Jeep switched to the external slave cyl in 94.  If you have an int. slave, you can swap the bell housing from a 94+ trans for the ext slave.  If you have the BA10, there is no ext slave options.  You have to keep swapping int slave cyls.

 

2.5: The AX5 was the transmission with the MJ.  It was int slave cyl.  The AX5 looks very similar to the AX15, but are not inter-changeable. The bell housing bolt patterns are diff.  If you can find a Dodge Dakota with the AX5 from that time period, the bellhousing was ext slave and fit the Jeep 2.5.

[gai092460]

Sorry 1989 4.0 L  182K on original motor 

[87MJTIM]

What transmission do you have in it?

 

The BA10 case splits in half from front to back.  The AX15 come apart in three sections.

[gai092460]

BA10 5 speed trans 

[Eagle_SX4]

I used a BA10 master cylinder with the AX15 slave (both internal and external) with no issues other than longevity (seals started leaking). You should be able to use an AX15 master with the BA10 slave with no issues. 

[gai092460]

Thank you for your response quick  recap 

 

Options

 

1) I can  retain my 89  BA 10  trans upgrade the Slave Cylinder and the master Cylinder same part as used on AX15 that should work ,with simple hook up no revision required ?

 

2) Upgrade my complete trans from 89 BA 10  to 1994 or older AX15 trans ,are there many modifications required with this upgrade ? Has this been performed many times 

 

with other members of the club ?

 

Kind Regards 

 

George 

[fiatslug87]

Here’s a a how-to for the swap, I’m sure there are a lot more on here.

According to Rockauto the masters are the same but slaves are different.

[87MJTIM]

If you stay with the BA10, the int slave cyl for an AX15 is compatible with the BA10.

 

If you go for the AX15 swap ext slave cyl, you will need a list of parts:

1. AX15 with ext slave cyl bellbousing, plus the internals of the bellhousing.

2. NP231 transfer case with 23 spline input shaft. (Your existing TC has 21 splines and will not fit the AX15.)

3. The transmission cross member and transmission mounts.  The cross member for the BA10 does not have the drop section the AX15 requires.

4. An external slave cyl, or buy a pre-bled hydro master-line-slave kit.

5. TC shift linkage.  There is a diff between the two transmissions linkages.

 

Others may add to the list.

[87MJTIM]

One more thing:

 

The AX15 input shaft tips have two diff sizes.  Early models (89-93) have tips that are ~1/2".  Later models (94+) have a 3/4" tip.

 

You will have to replace the pilot bearing/bushings with your MJ if you get the later model.  I found that the bushing for a '75, CJ5, w/ a 304 cu. in. engine fits.  Search RockAuto for the part.

[Htchevyii]

Hopefully you can find a complete assembly with the external slave cylinder from a later model. If you end up with an early ax15 or a brand new one and want to swap to external, my video might help. After my LUK internal slave failed 500 miles from home (10,000 miles after replacement), I replaced my ax15 with a brand new one from Advance Adapters along with their external slave conversion kit. 

Here's the video of me driving the MJ 500 miles home without a clutch. 🙄