This is for the replacement of the vacuum controlled 4WD actuator in the front axle of my '89 YJ. It really was an extremely simple swap that took less than 1.5 hours. I purchased the motor from Advance Auto for $82 after they matched an internet price. The box contained the following:

1 shift motor
4 bolts and lock washers
1 large and small e-clip
1 o-ring
1 cover gasket

Instructions:

1. Jack and support vehicle if you feel necessary and place something to catch oil under the motor cover(I used a towel)

2. Remove 3 vacuum lines going into shift motor

3. Remove 4 bolts in each corner of the cover and pull cover off; it may take some prying and pounding
This step frightened me as 3 of the 4 heads snapped right off leaving the rest of the bolt. I sprayed the remains with an rust loosener and let them sit for 20min while I worked on replacing the shift motor in the cover. I then took vise grips, clampped them on as much of the bolt remains as possible and they came right out. I think the corrosion in the cover is what did them in, I was able to remove by hand after the first turn.

4. Once the cover is off you need first mark the fork location in reference to the housing and then remove 2 e-clips holding the motor shaft in place. One is on the shaft and the other larger one is against the cover holding the motor in there tight. This was a pain to get on and off and took the longest. I ended up just breaking it since a replacement was included.

5. Place the new o-ring the the new motor and slide it through the housing and into place. I put a drop of oil on the o-ring to slide it into place easier. The shift fork must be in place for the shaft to slide through.

6. Put the new large e-clip on first, this too was tough. I used channel locks to force it down into place. It is a very tight fit and may take some time to get in place. Next replace the e-clip on the shaft to hold the fork in place; this one was much easier.

7. Sandwich the new gasket between the axle and motor housing and tighten in place with 4 bolt and lock washers.

8. Hook it up and you're ready to go.

I do have some pictures I'll post up later, but it really was very simple and nothing was hard to find. Hope this helps someone in the future.

Great write-up. I will sticky this, because I know it will be useful to someone. Please do load your pictures when you can.

Sorry I dont have more or better, but once I put them on the PC some didnt come out too well. This should be enough to get it done. Let me know if you need help or have questions.

Picture 46-1 shows the location of the 4 bolts on the axle

2-1 shows in the axle with the cover removed

1-1 shows the cover removed with the new and old shift motor

Sticky, Your recipe for the four wheel shift motor replacement was fantastic. I am having a problem with the same stuff. my delema starts with the kid that owned my 92 yj before me being a Jiffy lube mechanic thinking he new a bunch and Mickey Mouse is now a common term I use when referencing my jeep. Instead of replacing the vacuum motor with new stuff he installed a 4x4 Posi-lock. Allthough I get the convenience angle Its the cheap way out. Would you have any advice for me dealing with having to uninstall the posi-lock and wanting to install the orginal equipment? I think its really important for me to do this. The cable is not the greatest for me. Thanks. P. S. No offense to any Jiffy Lube mechanics who know what they are doing should be inferred.

another question for ya.That guy tore out the vacuum lines. Any ideas on where to get besides the dealer. The one in my area knows more about dishwashers than jeeps. Sorry about the lack of basic auto knowledge on my part. This is my new found source of unconditional love.

[QUOTE=porkchop71;86782] Would you have any advice for me dealing with having to uninstall the posi-lock and wanting to install the orginal equipment? QUOTE]
Yes. dont do it. I just installed the posi-lok and love it!!!! When its in you know its in!!!! My 4x4 light even works now

As for the vacuum lines, you'd be surprised how many folks run a posi-lock and have the vacuum lines in a box in their garage. Try posting a "want to buy" on a couple different 4x4 forums and see if you get a hit if your not in a big hurry.

Ask your parts guy at the dealership to check Jeep PN 53002033 and see if that's the part you're missing. It should be the harness that runs from the transfer case to the shift motor.

I don't know that I would call the posi lock the cheap way out. I installed it an it was one of the best upgrades Ive done. It locks in when I want it to and can be done on the move. The vac. system just has too many parts that can fail (one reason it was only used 3-4 years, Its a flawed system) but then again some guys swear that its better than the lock. To each thier own i guess. Just my 2 cents

Where is a good place to buy the actuator? I found one for $70 or so online. Im now sure a good parts place.

THanks,
Bob

i used a permi-lok (like a posi-lok but no cable. it is always locked for 4x4) because who in their right mind would spend money on a D30?

how much trouble was it to swap the GM parts into your Jeep on a scale of 1 to 10 do you think?

i agree the posi-lok was the first upgrade i made when i bought my 88 yj
that was 5 yrs ago, u dont have to worry about stuff cutting or yanking
off vac. hoses

What happened to the pics for this write up?

helllou?

It is really great write up.

lol i looked at mine today, to see if it was worn and needed replaced, come to find out the guy thats had it before me, some how used a bolt and a nail to perma lock it, but o well works good off road

^2 where the pics go?

were is a good place to find a posi lock becouse i just got my first yj and the actuator is busted and i found a used one for 50 should i even bother or just go with the posi lock instead

I had alot of problems with my four wheel going in and out. I think the cable is messed up. Some times I could get it to catch and sometimes not. Im not worried about the whole I want original equiptment thing. I just really want to have my four wheel bulletproof. And have it want I want it. It might be time to put another cable in. The one in there is at least seven years old.

Im new to the WF, but i have replaced the shift motor before. You r right on with the steps. I did eventually get away from the vacuum though and went with the cable engaged system and am very happy with it so far.

Quadratec has some good parts. i get a lot from them