My track rod bushings are completely shot, so bad I've had to park the car until I replace them. It caused the outer edges of the tires to wear.

-J

Did you replace sway bar bushings? I had that same noise and it wad thee sway bar bushing. I replaced it and still had the noise. Went back under and retorqued it and and the noise was gone. Except I had the popping on the passenger side and all other front end suspension parts were rebuilt.

This is off-topic now but I'll share it anyway - Wagenswest—Bus Vanagon Ball Comparison

Money shot -

http://www.wagenswest.com/how_to/how...s/IMG_6155.JPG

Sixto
87 300D

Are you talking about the two bushings on either side of the upper control arm where the tip of the sway bar passes through? If so, then yes those were replaced. Another thing to note is that as the popping has gotten worse, I sometimes get two quick successive pops.

I'd say guide rod bushings. I've done several W126 FE and this part is a common failure.

Any chance you put the springs in upside down? I don't see any way the rubber cup would shift otherwise.

The spring is in there right side up. The top side shim isn't way out of place, it's just not as perfect as the passenger side. Bad guide rod bushing doesn't explain the wobbly steering when the wheel is far to the right which is why I'm starting to think it's the center link. The one that's on there now made a horrible popping noise when I first installed it and then it hardly ever popped a week later. I didn't know if it was because the link was bad, or that the stiff ball joints on it were putting a lot of pressure on something else.

It must be the center link then. A bad ball joint on the passenger end of the center link bar would probably give you the wobble you talked about.

I just thought of an approach that might give me an answer. I'll raise the front of the car with a jack, turn the wheels all the way to the right and the rest the front wheels on ramps. I'm hoping that by either bouncing the front end or tugging at various linkage, I can recreate the noise. I don't want to start throwing parts at this problem without certainty, especially if involves removing the springs again.

If it makes you feel any better, here is a driving video of my 300SE parts car. The clunks, grinding, thumping and vibrations are coming from the front end.

Parting out Mercedes Benz 1990 300SE drive test - YouTube

Water makes a difference
 

So for the past couple days we've seen a lot of rain here in the Bay Area. The popping sound in my front end became much less frequent and sounded more like a clunk than a pop. It seems to me that there must be a bushing that was getting lubed by the water and that had an affect on the pop.

It was dry today and the popping came back just as loud and frequent as before. I took my garden hose and sequentially soaked the four primary suspects: guide rod mount, lower control arm bushing, ball joint, upper control arm and bushings. After soaking each part, I backed out of the driveway and turned the wheel hard to the right and each time I still got the loud pop. Can anyone think of some other part that the rain would have an affect on? I have the spring compressor and am ready to do this job, but I need to be certain before I start taking things apart. Thanks

It may very well be the rear sway bar links....

Today I sprayed water just on the pitman arm and upper spring perch. The popping subsided after driving around the neighborhood for a few minutes and making about 10 right turns. Next time I'll just spray the pitman arm and see what happens.

Found it
 

The noise has been coming from the inner bushing on the upper control arm. After spraying the inner bushings with silicone spray, the pop went away almost completely, and the few times it came back, the pitch was much lower.

Which brand UCA should I get. I'd like to save money and just get the bushing, but I don't have a press.

Does anyone want to purchase a Baun MB spring compressor for $140 plus shipping? Only used for about 15 minutes.

Of the ones on offer here =>

1981 Mercedes-Benz 300SD Base Sedan - Suspension, Shocks & Springs - Page 2

I'd pick the TRW