YJ: 4WD engagement issues

[Mike]

Okay, I need some advice from the YJ folks out there. A friend just bought a 1990 4-banger that seems to be in pretty good shape except for two things:

1) The transfer case shifter was not adapted for the 3-inch body lift that is has and it can not be shifted into 4WD.

2) When in 4WD (I disconnected the linkage and shifted it into 4low from the T/C), the front axle makes a nasty popping noise when turning the Jeep. It actually shakes the front of the Jeep.

I need advice. On the first one, what is the cheapest way to effectively fix this without removing the body lift? For the second, what do you folks think? Vacuum actuator?

[6spdYJ]

The shifter boot has an inner boot that needs to be cut out of the throw path of the lever. This happens with any change in height between the T/C and body.

Check to make sure none of the vacuum tubes are cracked or off on the T/C - axle connections. The vacuum diaphragm sometimes cracks. Check bc4x4.com YJ FAQ's for a way to set up a cable control for about $20.

[dr.dirty]

Sounds like mine Mike the pass side axles is goobered up. the Vac disconnect on mine was toast because the guy never used 4wd. i just havent gotten around to fixing it yet

[Mitch]

Mike,

I have a stock passenger side 2 piece original axle laying around. I also have a Posi4x4 cable set-up that bypasses the vacuum actuator. I went with the Superior Chromoly 1 piece axle set for the front, so the vac is gone as well as the problems.

Mitch

[Materdaddy]

On the first one, what is the cheapest way to effectively fix this without removing the body lift? For the second, what do you folks think? Vacuum actuator?

I know how... lose the body lift! 3 inches?

[Mike]

Mike,

I have a stock passenger side 2 piece original axle laying around. I also have a Posi4x4 cable set-up that bypasses the vacuum actuator. I went with the Superior Chromoly 1 piece axle set for the front, so the vac is gone as well as the problems.

Mitch

So can the existing axle housing be converted to use the standard single piece axle from a TJ? I have an axle that I can give him if this will work.

If so, what do you have to do with the vacuum lines that run back to the T/C?

[RAT]

I have a question. Was the Jeep on pavement when you were driving it in 4 wheel?

[Mike]

I have a question. Was the Jeep on pavement when you were driving it in 4 wheel?

Yes it was, we were at a very slow pace but mine doesn't make that nasty popping noise on the pavement. Is a YJ different?

[OU812]

I swapped to non-disco shafts. I used XJ/TJ shafts. I used Napa part number 11800 for the passenger side seal which I placed in the axle tube right by the pumpkin not in the disco housing. I used the stock size seal on the driver’s side which is NAPA part number 11899. The collar that connects the two piece shaft is not really a weak point unless you are having trouble engaging it. If you have a pre 95 though you get the smaller u-joints which are a week point. I didn't notice any fuel mileage drop now that my front drive shaft spins while I am in 2wd. But I do appreciate not having to wait for the vacuum collar to engage.

[USMC 0369]

[COLOR="Sienna"]My super cheap fix was to take apart the vacuum diaphram on the axle tube, put in a small piece of tubing (I cut a front spring eye bushing) onto the shaft so that it holds the locking ring in the "locked" position at all times. It's held up to my abuse so far. But I am planning to go with the Superior one piece shafts like Mitch did. As for the transfer case vacuum lines, I got rid of those at the same time, just capped off the fittings on the T-case.[/COLOR]

[freewaydan]

So can the existing axle housing be converted to use the standard single piece axle from a TJ? I have an axle that I can give him if this will work.

If so, what do you have to do with the vacuum lines that run back to the T/C?

Mike I did this to my heep.
http://www.stu-offroad.com/axle/yjd3...jconvert-1.htm

[freewaydan]

Just take the posi lock cable put it in the trash, and do the conversion

[Mitch]

Good info and article. I do remember Ken needing to hand grind a recess in the axle tube to retain the seal on the inner side. On the YJ's that section is dry and does not have a spot to set and retain the seal. Just 2 cents worth.

Mitch

[Mike]

Right on! I knew that the YJ guys would know how to fix this. Thanks Scott, Nick, Dan, and Mitch. I have a set of the YJ axles with the smaller U-joints that I will give to my friend.

All that will need to be purchased are the seals and I can do the work. You guys ROCK!

As for the body lift, it is staying in place for now, so I think that I can fab an adapter to compensate for the lift.

Hopefully, we will have a new Jeeper on the trails with us soon. Thanks everyone.

[freewaydan]

mike I have the tool to install the seals inside the tube if you need it. Just call me