esde

My 98 2500 4WD started doing this after this particularly rough east coast winter. Runs fine in 2wd, shifts fine and runs fine in 4wd. I have a steering box brace, new tires, track bar and tie rods. When I shift from 4wd to 2wd, and then take a corner, I get a wobble form the steering gear. It is consistent with road speed. Seems to me that one or both steering universals are binding, but then wouldn't it do this all of the time? Why just when going from 4 to 2wd? The universals that are in do not have grease zerks, is there a good replacement that can be greased? I have to have the front apart soon for new control arms, rotors, and calipers, so it would be helpful if anyone had an idea as to what else I might need to replace. Thanks, Seth

Hodge

I would look closely at your axle u-joints. In 2WD, they turn, but they are not connected due to the CAD, and they are not mechanically linked to the rear through the transfercase. So, they don't bind. When the truck is engaged in 4WD, then you get driveline binding, which is normal. But, this binding will manifest itself if the u-joints are bad.
I just bought off the shelf u-joints from a quality, local parts store, and they have grease fittings. You should be able to find them.
If you are going to have it torn down to the point of pulling the axles, take a close look (listen) to your wheel bearings, and your ball joints.

Hercules

I agree with Hodge, check the axle u-joints at the front wheels. I had one go out on me last year. At first, I began to notice the truck wanted to wander more than usual. Then, I started to feel a bump through the steering wheel that would pulsate with each revolution of the wheels. In my case, it didn't matter if I was in 4-wheel or 2-wheel drive. There was no noise being produced by the bad u-joint, which, was the first time I had ever seen an axle u-joint be quiet when it was bad. Also, I was not able to make the u-joint move with a small pry bar when trying to isolate the problem, which was a first for me, too. Usually, I can get the u-joint to wobble in its cups or hear it, letting you know its bad.

I found mine by raising the front end, had my wife turn the steering wheel slowly in each direction while I spun each front wheel until I felt it bind. I spun the wheel slowly with a hand always on the wheel so I could feel something when it happened. Once I isolated the wheel where the problem was, I just started working my way in checking each component...ball joints, wheel bearing, u-joint. About the noise thing. I could not hear any noise until I used a screw driver to amplify sound. Place one end on, or near, the part your testing and hold the the other end to your ear. The end your holding to your ear, you should grasp the rod, or screw driver so that you can press the side of your fist against your ear without letting the screw driver touch your ear. To understand how it works, make a fist with your right hand and press the thumb and first finger side of it to your right ear. Now, lightly rub the other side of your fist with your other hand. Do it just hard enough so that you can't hear it unless your fist is held to your ear. Put a rod or screw driver in that fist and you've now just made a way to reach the parts. It's a make-shift mechanics stephoscope and does work. Hope this helps give you a way to possibly isolate the problem. Good luck.

Hodge

Mine was bad on the passenger side, but made no noise and did not bind. I had that side jacked up to check the ball joints, and saw that it had movement. All the needle bearings were gone. As in MIA. I had planned to replace them since the axles would be out, but didn't expect that. Oh well. Moving parts wear out.

It does make sense now. When I first got the truck, I greased the axle joints, and when I did, a puff of dust came out as I pumped grease in...