Car: W124 250D 1987 Manual - Euro

There's a humming cound with vibration when I am low on any gear. Meaning if I on third and running a bit slow it would vibrate. I would have to down shift of accelerate to loose teh vibration. This happens in all gears. Does this car like "high RMP" always? I notice that the vibration stops when I put it on Neutral that's why I think it could be he drive shaft. Flex discs are all new. Any other possible causes?


Thanks!



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94' E280 Euro
85' 300D Euro
87' 250D Euro
77' 300D Euro
Manila, Philippines