94 EB Explorer 4WD not engaging correctly

Hi! We have a 94 auto hubs with approx. 141K. About two months ago it started to feel like the 4WD was engaging by itself , pulling to the left, and making a whizzing, chirping noise. We took the car in to a local mechanic who said we needed work done on the front axle and possible replacement of the whole thing. We decided to do the work ourselves and replaced the driver side spindle (it had a slight bend in it which we thought might be why the tire was shaking) and inner bearing on the spindle, wheel bearings on rotor, and we replaced the hubs (purchased from junkyard). Prior to doing this the 4WD would not engage at all. Now, in low range (with the car jacked up) the passenger side wheel turns but the driver side does not. In

4WD the driver side turns, the passenger side does not, but the driver side wheel starts to shake and the steering wheel shakes and pulls to the left. Can anyone provide any suggestions on what to check next? Thanks for any advice.

There's a bunch of info posted at

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That's Jeff Singleton'scompilation of info gathered from this newsgroup. Look in the fronthubs and brakes sections for some info on the hubs. For your problem:

Look at the u-joints in both sides of the front drive. They get stiff as they age, and can cause partial and/or incomplete engagement of the front hubs. On the right side there's a sliding section of the half-shaft that must be libricated regularly. Both of these tasks are best done with the spindles removed.

The stub axle inside the spindle rides on needle bearings that need to be greased regularly. If the bearings are still OK you can add grease using a needle extension on your grease gun. Othereise the bearings get replaced while the rest of that stuff is apart for the u-joints.

Operation of the front hubs depends on having all that stuff working smoothly at all times. A little binding will wreak havoc in the system, and will often cause secondary damage to those expensive hubs. Many owners just replace the hubs when they get that damage, and end up getting even deeper into the problem only after that second set of hubs is damaged.

Good luck with your project. You'll find a wealth of info in Jeff's archives.

dr bob