89MtnXJ

So the slave cylinder went out on my 89 xj. On top of that 1st & 2nd gear synchros are bad and the trans whined real bad so I want to replace it while its out.

What years and models will fit without any fab. My driveway is mud, snow and rocks so I'm gonna pay the neighbor kid that just graduated from wyotech to do it and I don't want any hiccups.

Out of what will fit are there any that have a closer gear pattern? I live on a mountain and the 1100 rpm difference between gears is a pita.

Sorry if this has been answered but the search function on the mobile app isn't working for me.

dukie564

any AX-15 will work and bolt right up in place of yours. They can be found in any late 89-99 cherokee 4x4 with the 4.0L engine. Gear patterns are all the same sorry - you need to regear the axles if you're down on power with bigger tires.

Now the issues:

1 - an AX-15 out of a 89-91 XJ will bolt right up, no mods or issues, but retains the internal slave cylinder

2- an AX-15 out of a 92-99 XJ has an external slave, but requires you to adapt over the hydraulic line, and requires you to replace the pilot bearing with a different one since the input shaft tip on the later ax-15s is a bit bigger. This is the bushing in the center of the flywheel. Not terribly hard to replace but requires you to remove it (autozone loans out the correct puller for this job). Advance Adapters sells the new bushing you need:
http://www.advanceadapters.com/produ...d-x-950-thick/

89MtnXJ

Good to know, thanks.

So would you say the newer one is stronger? Is the input shaft bigger all the way through?

The extenal slave would be nice...

dukie564

no they're the same strength wise. Just the pilot tip is bigger.

external slave is a big benefit though

LaredoBucket

He's pretty much right but his years for the slaves are off by a lil according to this link: http://www.novak-adapt.com/knowledge/ax15.htm
It definitely helped me out alot.


I had to replace my internal slave in my 92 a couple times and also rebuilt my AX-15 for dirt cheap, luck me. Remmeber to get your flywheel resurfaced, check your clutch for wear. Tranny dolly will definately Help! you can rent them from AutoZone and such. I used my floor jack, blocks, scissor jacks and alot of muscle on mine. It's not a fun job, but I can do it alot faster now. HAHA!! "Remember to Pre Bleed your NEW Slave Cylinder!!" It makes bleeding a hell of alot easier & faster. I used a fuel line and small funnel and poured fuild in until it overflowed and the capped the both lines with fuel line and a couple bolts so the fluid didn't leak out or no air got in. Let me know if you need anymore pointers. Cheers!!

LaredoBucket

Also, If you want to regear your rear, it may be easier just to find a 8.25 from a 97+ or D44 from 87-89yrs they both come with beefier gears and stronger axles. Look for one out of an "automatic" or auto with "tow package" and you're set. Even a 4 cyl will do the trick, they come with 4.10 gears opposed to your D35 with 3.07 gears. They are all direct bolt in. I picked up my 8.25 with 3.73 gears at the Junk Yard Pick A Part for $200. Good luck!

mud-dog27

ok so as said the initial years given are a few years off the internal slave ran till '93, '94+ was external slave.

the next issue is until '91 the clutch line is your basic 7/16 threaded fittings, in '92 they switched to a push in roll pin fitting, Advanced adapter can help you with this issue....fixes run from $15-$75ish depending if you just go with adapter fittings to allow use of OEM line or you can go custom steel braid line.

the pilot bearing you need will be from a '74 CJ with a 304 V8/T15 setup, and its just a brass bushing not an actual bearing, you can get sleeves to make the bearings work but the '74CJ option was cheapest and easiest, if you need i think i still have the box from mine that i can grab a part number off of. The reason for all this is nothing to do with strength just the fact that the earlier ['93-] 4.0L bearings were larger OD smaller ID and the newer ['94+] were smaller OD larger ID.

only way to get a different stock gear set would be if you were to pull from a toyota ,chev ,dodge but even then there is no significant difference

89MtnXJ

Thanks for all the help. No progress yet, my expedition spit a spark plug out 2 days ago so I'm hot on replacing the head in that first. Having no car sucks!

I think I'll look for the external slave trans first. I'm real easy on stuff so there's no reason to ever have to replace the trans again, therefore no reason to have to remove it again.

mud-dog27

yea but **** happens

hankthetank

Ive done my slave twice last year...second time around I bought new master, adapted from -4 flare to -4 an fittings and an earls stainless line. And obviously new fluid. Oh and I just gravity bleed the line...pour it in, have a smoke, pour more in, crack a bud, pour more in...then wedge the pedal down with something long enough and cap it...cause I'm too cheap to buy a bleeder kit...

The internal slave isn't THAT bad...the first one was a cheap overseas unit, this new one is a Timken, hopefully its good...