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Had a sort of thrumping, rumbling..almost like driving over loads of mini cattle grid type noise/feeling..whilst accelerating..goes when cruising..and isn't present when no load ..ie coasting.

Thinking maybe prop, engine/gearbox mounts..etc..

Popped her over to a mate this morning, who took her for a little test drive...noticed the problem and floored it in 1st...resulting sound was frightening...he cried prop, then gingerly drove her back.

Had a quick look underneath when I got home, as unfortunately he was unable to spare a ramp this morning

Seems the donut has hit the gear linkage..and the prop a little further down has hit a jubilee clip on the linkage ( not sure why that is there )...

Anyhow...any ideas as to cause?...must have flexed loads to do that..right at the joint as well....donut looks OK..no obvious signs of wear/deterioration....maybe a cheap pattern one perhaps ?

K

Hi Keith,

I had the same situation for a while, and it turned out to be the propshaft donut. I'd give that a good check first.

Sounds like a flex disc torn apart, or a bad flex disc. I've seen this with aftermarket flex discs like from WallothNesch, they use cheaper and softer rubber so under load it starts hitting the gear linkage, had the same issue here with a brand new but not oem flexy disky.

Thanks for the responses gents..

I saw your post Arshad...and thought it might be a related issue.

Going to order the donut from my BMWD....they give me a 20% discount so its the VAT saved at least.

Reckon I should check engine & gearbox mounts also....maybe worn/damaged...or can they be out of alignment perhaps?

K

Sounds like donut to me and/or gearbox mount?