I was on my way home from my Indy in heavy snow. Because of the snow I was driving at low speeds (between 20-40 mph) and losing traction from time to time. The roads were level. Periodically I would get a massive, whole-care vibration that felt like someone was holding a giant palm sander to the car. This seemed occur on acceleration or deceleration and didn't seem to be speed dependent or even engine speed dependent. It was went away before the drive was over.

My Indy replaced my water pump and re-sealed my secondary transmission pump. I can't imagine how either of those things could be related to the vibration.

Any ideas?

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1985 300SD 99K

If the secondary transmission pump reseal required the removal of the driveshaft. It all needs checked. My guess is is something he did or did not do in that area. Could be a couple of things I can think of. May even be a partial part failure just from the normal manipulation they were exposed to during the job. Like getting them out of the way.

.It could have stopped when something restored itself to the proper position. If that were the case there may be nothing to find now.

collapsed motor mount?

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Ice rubbing on tires?

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

My Indy said they didn't have to move the driveshaft to get to the secondary pump. Ice/snow in the tires or wheels was my first thought but the frequency of the vibration was so fast and my speeds were relatively slow so it just doesn't seem to match up. You could hear/feel the whole frame and body of the the car vibrate like driving over a rumble strip at high speed. Only this was happening at low speeds.

My Indy is being responsible and paying to have it towed up to his place to look it over even though we both are having a hard time figuring how what he did might have caused this.

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1985 300SD 99K

Is this from the frozen truck tire tracks left in the snow from a snow plow? Test, try on a clear road

I don't think it is road surface related at all. It was happening on un-plowed roads. I will be driving it home from work tonight so I will see if it happens again.

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1985 300SD 99K

Flex disk ?

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1985 300D 198K sold
1982 300D 202K
1989 300E 125K
1992 940T

"If you dont have time to do it safely, you dont have time to do it"

"The democracy will cease to exist when you take away from those who are willing to work and give to those who would not."

My first thought was axle shafts... they perform like that when failing. randomly smooth, then at a certain angle they lock into a wheel hop like fashion...

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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!

Drove the car home yesterday and back to work today. So far no repeat of the symptoms. Axle shaft is believable to me since one of mine leaks. I need to get a repeat of the symptoms in non-blizzard conditions, though, since it is hard to diagnose problems when you're struggling to stay out of the ditch. The W126 with all-season tires is not a very good snow-ride IMO.

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1985 300SD 99K

Following in tracks of a vehicle with chains on will do that too...

Just out of curiosity, what was the symptom that cause you to rework your secondary pump?

The secondary pump was resealed due to a leak.

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1985 300SD 99K