Hi Dan,

I'm not recently practiced with auto transmission equipped driveline vibration.

Yet the FAQ can get discussion going.

https://www.brickboard.com/FAQ/700-900/Driveline.htm

If vibration appeared all at once, where before the driveline vibration start you encountered none, the loss of a wheel balancing weight or (unlikely) a drive shaft balancing weight.

I've found the smaller driver side motor mount can appear unfazed, yet it is split, as the engine lifts up on the driver side and pushes down on the passenger (oil filter) side when revving. All three may mounts require replacement?

If the center support bushing has shrunk, the drive shaft can wander around through the center support housing. Maybe low speed sensations. The shrunken bushing can shift in the hanger housing at low speeds (more torque) when accelerating and slowing down. More noticeable with a manual transmission.

Does the vibration start at speed and continue? Does it 'balance' at higher speeds.

Maybe more under-Volvo 240 wiggle time?

Hope that helps.

Dud.
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