I have a 89 cherokee
Is a 4.0 5 speed
When I try to engage 4wd high or low it engages but the passenger rear wheel just spins even if you are on asfault and it barely moves frwd

 

Couple of things here.

Which transfer case do you have?

On the back side of it near the drain and fill plugs are located is a number.

Let's have that.

Speaking of drain and fill plugs, have you ever checked the transfer case fluid level and condition?

 

How do I check the fluids/ condition

 

There's a fill plug and a drain plug on the back of the aluminum transfer case. Remove the top plug. That's the fill plug. Does fluid run out? Is it just below the hole? What does the fluid look and smell like?

If you don't have the skills/tools to do this, have a shop do it during a routine lube job of all the grease fitting in the steering and drive train components.

 

It's a new process gear
Model 230 j
The gears are
88 86 87

 

Should be a 231J.

Your front axle has a vacuum operated disconnect which is trouble prone. Eliminate the vacuum crap using this link:

https://www.cherokeeforum.com/f51/fr...ss-91-a-38629/

And here's why to do it:


The big issue is that the CAD system only fails when you need it the most.

Kinda like when you don't realize your wiper blades need replacing until it rains....

I know somebody’s system works and he advocates keeping it stock, but my exposure to the failures is probably hundreds of times greater than his, as a result of being Service Manager at a Jeep dealership from 1980 through 1992, and being a current XJ and MJ owner.

CAD stinks. Every Jeep I work on with it, I eliminate it. Guess what I find in the process? 25 year old busted vacuum lines, bloated vacuum line connectors, bad vacuum reservoirs and piping, bad transfer case vacuum switches. In other words, had the person gotten into a sticky situation and needed 4WD, they would have been screwed!!!

That's the tip of the iceberg. The factory went through 3 revisions of the shift fork also. The fork issue is non-existent if you just slide it over and leave it.
,

 

Sounds good thanks for the advise I will give it a try and see if it works.
Just curious do you loose anything from bypassing this system like is it going to be in 4high all the time now?

 

Nope. Won't be in 4wd. That's what teh lever is for.

 

Ok awesome thanks again you where a lot of help. I will let you know tomorrow if it works