Stupid front axle Shift motor thing!!!

I was wheeling this weekend and I heard a loud pop (bore like a bang!) Everything was fine for about 20 minutes or so untill I was trying to go up a hill. My front wheels were not moving while I was in 4LO. It went and then not. No other noises from the front axle driving in 2,4H, or 4L. I checked the vacuum lines and they apear good. I took the cover and shift motor out...all seems good...no cracked fork. The colar moved free...but when I pushed the collar to the right (pass side) I had to pry it with a flat head to get it back over to the engaged position. I'm tired of screwing with it. Is there a way to lock it to the right (engaged)? What are the pros? Cons? What about a one piece axle shaft and take out the vac?

I did search the forums, but didn't find what I was looking for.

Thanks

MIXEDBREED said:

I was wheeling this weekend and I heard a loud pop (bore like a bang!) Everything was fine for about 20 minutes or so untill I was trying to go up a hill. My front wheels were not moving while I was in 4LO. It went and then not. No other noises from the front axle driving in 2,4H, or 4L. I checked the vacuum lines and they apear good. I took the cover and shift motor out...all seems good...no cracked fork. The colar moved free...but when I pushed the collar to the right (pass side) I had to pry it with a flat head to get it back over to the engaged position. I'm tired of screwing with it. Is there a way to lock it to the right (engaged)? What are the pros? Cons? What about a one piece axle shaft and take out the vac?

I did search the forums, but didn't find what I was looking for.

Thanks

Click to expand...

Yes.

The fork and collar can be locked over - you just have to put spacers in on the shaft to keep it from walking back to "disengaged."

The axle shaft can be exchanged for a one-piece unit. You have to change the seal and a couple of other things - I know it's been covered here. Either the shift motor is left in place and sealed up, or a "blanking plate" is made to cover the hole.

Or, you can use a cable-operated shift (like an Ox, I think) or convert it yourself - but if you do that, check the splines on the halfshafts to make sure they don't need to be filed and cleaned up.

Last, you can also swap out the front axle entirely - I think the CAD (Central Axle Disconnect) finally went away for 1992. Up to 1999/2000, you should still find high-pinion D30s, 2000/2001-up are low-pinion, and you'll lose some front driveshaft articulation. You should be able to find D30s under YJ/TJ/XJ/ZJ and MJ that should work, although the YJ/TJ versions may be a bit narrow (the XJ axles are 60.5" WMS-WMS, IIRC.) The XJ units will be a direct swap, the MJ should be, and the YJ/TJ/ZJ might require a little work.

Welcome to the club!!! The Dana 30 Central Axle Disconnect has been the thorn in almost all early XJ owners sides....

My 87 CAD gives me about a %70 chance of engagement on the first try....

Either swap axle shafts or install the above mention manual disconnect.....

Search around . There is a thread on the spacer install(it's a bunch of washers) with pictures. I'm guessing the bang you heard was the collar popping out of engagement.

There is no real downside to disabling the disconnect. As was mentioned, the factory did away with it on later production.

My friend had the cable actuated thing. Sometimes it failed as well, so we shimmed it over and locked the shafts together full time.

There are 3 ways to dis-able the CAD on a X/MJ,

1st way, was mentioned already, use washers to lock the fork over.

2nd way, unbolt the CAD and flip the whole thing over and re-install.

3rd way, unbolt the CAD, remove the pin snaprings holding the fork in, flip the fork over and re-install the pin and snaprings. Basically the same thing you have to do to put the washers in.

Actually to be completely honest with the exception of vacuum issues (which I permanently solved by replacing the crappy OEM lines) I've had no problems with the front axle disconnect.

I ran it for about six years in the red Jeep and have been running it for two in the Chief. All you have to do is know what it is and what may be a problem and slip it into your maintenance schedule (changing the oil? Check the disconnect).

However... I would (and have) change it out in a heartbeat to run stronger axles or for any other good reason. The red Jeep no longer has it and I may nix it in the Chief when I put a 242 in it (have to check a couple of things out first though).

Sequoia

PS - The only real con to either shimming the disconnect or converting to a solid shaft is an alleged minor loss in fuel economy.