I have a 1978 300d... and when driving there is a vibration that is not constant but on and off but it stops when i put it in neutral while driving... the flex disks look good I am going to start with the motor mounts and trans mount.

don't forget to check the muffler donuts, when they sag, the exhaust makes odd racket too.

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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!

Do you have a center bearing?

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According to the diagram I do. The support bearing right?

Mine is worst at 55 mph. Same car too, 1978 300D.

Please reply to let us know how you fixed it. Same exact sound and behavior. I'm thinking motor mounts, because taking it out of gear lets the motor go back to idle.

But, I have been wrong before, very wrong.

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1978 Mercedes Benz 300D. Butter color, named "Larry." (Bought out of a barn in Caldwell, ID with a vintage "Larry Craig" sticker on it.) 229,000 miles, dark brown interior, need map pockets!

1995 Suburban diesel, frybrid kit. 20k on veg, runs great.

Future mods, Frybrid WVO.

I will let you know I bought this car for $650 everything works and has good paint clean interior 302k miles i have been driving it for 3 mo without any problems now i am going to convert it i have a 1994 suburban converted with a modified greasecar system it works good 2 years and running.... I am going to get the valves adjusted this week and the guy said he will help me track down the problem.

Correct, may be in need of replacement. Crawl under car, and try to rotate drive shaft, back and forth.

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