311 Cdi Bad Vibration.

[alanred]

Hello,
My brother owns a 311 cdi, he does about 1000 mile a week, maybe more.
Just lately the van has developed quite a bad vibration, so bad that it snapped his exhaust and he's had to have it replaced.
The vibration starts at 1250 rpm, between 30 - 40 mph. If you dip the clutch whilst moving it still vibrates.
Today he got both rear wheels off the ground while his assistant (wife) revved the engine upto vibration speed, he checked (visually) the prop and it appears to be sound. He's checked both rear wheel bearings and there ok.
Today he's gone out and while still creeping forward slightly he put it in reverse, he said there was a "clunk" and after that there is no vibration.

Could any of you kind people offer any advice please.

Thank you.

[steel-jaw-sasha]

sounds like the dual mass flywheel has dropped to bits.

[alanred]

Just for the record it was the Prop Uj that had failed.
£180 later, job done, no more vibration.

Thank you.