Car shakes at 4k rpm plus, especially 3rd gear

[deadmau5]

When I accelerate through the gears, it's fine until I get to third gear from about 4-5k rpm. The whole car shakes noticeably. It's not wheel balance as the steering wheel doesn't shake.

I've checked the engine mounts and given the engine a proper good shove and it hardly moves. When I first noticed it I thought I was going over slightly bumpy road surface but then it happened again on perfectly flat asphalt. There's no difference to my mpg and like I say, there's no difference in performance.

 

[deadmau5]

It turns out it was the offside drive shaft. The boot had split and by the time I changed it there were no ball bearings and splines left on one of the three bits that goes inside the gearbox.

 

[JonnyGee]

when u drained the box did u manage to get many of the bearing rollers?

 

[deadmau5]

The driver's side is dry. Most of the rollers were sat in a big pool of grease on the plastic engine tray at the bottom.