I have a 95 Discovery that I purchased as a project. I repaired the CV joints and shimmed the axles properly. I ended up driving it a long way my first trip. The wobble began after some miles and got progressively worse at lower and lower speeds. What is the logical sequence to trouble shoot this problem?

Greg

 

When you say you shimmed the 'axles' do you mean the swivel bearings?

One easy and simple test for death wobble would be to jack up the axle so one front wheel is off the ground. Have someone in the vehicle. First test, you wiggle the wheel at the 6 & 12 O'clock positions, and then the 9-3 positions, and feel for movement. Let's assume you feel some movement. Then have the person inside the vehicle apply the brake hard, and repeat the wiggling process. If the movement goes away, or mostly away, your wheel bearings might need to be tightened (or investigated). If you still feel the same amount of movement, it's going to be your spindle bearings. And it could be both. Have your helper lift up and down on the tire (or use a bar) and you observe the swivel bearings top and bottom. At that point you should be able to see or even 'feel' movement. You can also remove the wheel and lift up/down on the outer hub with your hands or with a length of 2x4 and observe movement in the swivel bearings.

Do the same for the other wheel. If it appears to be the spindle bearings, the only thing I can think of is the bearings are shot ...and breaking up ..even if they were re-shimmed, and need to be replaced. I'm assuming you shimmed the bearings but didn't actually take apart and 'look' at them. If you replaced them before, then maybe the new race wasn't tapped in far enough and later worked it's way fully into the bore. That's all that comes to mind. There are some good youtube videos on the death wobble.

Good luck

 

Axle shaft end play was checked with a dial indicator. The swivel bearings and spindle bearings were not replaced but the swivel bearing preload was set with a spring scale for tension. and the spindle bearings set as outlined in service manual. The bearings were all thoroughly cleaned and appeared to be good. I think the problem lies elsewhere but I will make these checks. Likely when we come out of this deep freeze.

Thanks

 

After the swivel bearings and axel bearings you should inspect all the rubber/poly bushings on your radius arms and shocks. Air pressure in the front tires should be no more than 32 (and the manual says 26). Also check the steering damper (which is generally NOT the root cause but can contribute).

 

It seems like something changed as you drove along. So, if it were my truck, first I would check that the driver side wheel bearing nut didn't spin loose. Then, if you set the swivel pre-load with the swivel ball seals installed, that will be too loose, so double check there. I read somewhere on this forum that loose swivel adjustment is the main cause of d wobble. Then I would check out all the steering linkages. Then go after pan hard rod and drag arm bushings.

My steering wheel on the 94 used to shake a lot when going over train tracks, 30 - 40 mph at a slight angle. Never had the d wobble. Now after new bearings and thrust washers (but reused the upper pins and sleeve bearings), and very careful bearing pre-loads and new bushings, she is very steady over the tracks and through the woods.