I have had rotors do this.

I had a problem like this on my 84 500. Tires, wheels, rotors, front end rebuild (well anything that had any looseness in it), etc. Still had the vibration. Had the problem for several years and just could not get a handle on it. Some of the above work made it better, but not go away. You could see the fender shake. I bought a parts car from another shop (85 500) that had just had new brake rotors, wheel bearings, and pads replaced. My brake pads were getting low on my 84 so I just moved the whole brake rotors, hubs, with the new bearings from the 85 to the 84 and the vibration problem was GONE. The only parts that had not been replaced before were the hubs. I mounted the old left front hub in the brake lath and found that it was bent. It wasn't enough that you could see it by just spinning it on the car but it sure did show up when going about 55 mph.
Just an added note about another problem. About 2000 miles after I finally got rid of the vibrations, I started hearing a strange noise coming from the front of the car. Not bad but it just bothered me. You could only hear it while going straight at 50+ mph. It would change, but not go away in curves to the left or right. I first thought about wheel bearings, but they were new. Well, it continued for a few years. Didn't get any worse, or better. Just a very faint noise that I could hear. Well we planed a 2000+ mile trip so I brought the car in and did a full (I mean a FULL) service. I changed all fluids, lubed anything I could, and even pulled the front wheels and hubs, and cleaned the wheel bearings. Guess what I found. A bad inner race on the left front. While inspecting it I found the real problem, IT WAS MADE IN CHINA. New bearings made in the good old USA and the problem was GONE. 20,000 miles latter and all is still fine. No noises, no vibrations, smooth as glass and quiet from 0 mph to 100 mph. Two simple problems that took about 8 years to find. One original (on the car when I got it) and the other I put on the car when I put the hub with the NEW (but junk) bearings on it.

Paul

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84 500 SEL (307,xxx miles)

The tell tale signs of rotors is they should not vibrate after the car has rolled a few feet. And then when you apply brakes you get a vibration, not after the car is rolling and no pressure on the brake pedal.
Once the warped rotors push the pistons of the calipers back in there should be no vibration.
Also warped rotors if bad enough will generate a lot and I mean a lot of heat real quick.

Crazy question: can you swap wheels/tires between the 190D and the 300D to see where the vibration goes?

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."

yes, the rims are the same offset, but the 190 rims are much weaker, so don't drive much with them on the 300...
I'll bet dollars to doughnuts it's a bad cord in one of your tires... it'll balance fine, but still cause massive vibration...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

The only way you will ever feel up and down play in a 124/201/129 ball joint is to raise the control arm to unload the ball joint (car weight on arm)

Then take a long 2x4 and muscle the wheel outwards from the bottom or upwards - if it moves - your joints are shot. When I was checking mine the simple lift and wiggle way they were solid like new.

When I removed them with a press tool, they were so worn out that it was a darned miracle they kept the car on the road.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

if you raise the front by placing the jack on the LCA to lift the wheel off the ground, the ball joint is unloaded.

if you lift from the frame of the vehicle, FULL SPRING PRESSURE is pushing on the ball joints, and NOBODY will feel any movement.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

My experiences agree with this assessment. You should definitely move tires around and insert the spare to 100% eliminate tire/wheel issues before throwing money at suspension parts.

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You can't always get what you want, but if you try sometime you just might find you get what you need.

If you don't know the age of your ball joints on a W201, then the consensus advise I've read on this forum is to refresh them.

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You can't always get what you want, but if you try sometime you just might find you get what you need.