rear subframe bushings

[mcbonio]

I'm still trying to diagnose a rear end knock/crunch when the car takes off, I've replaced all rear end bushes except these...



My question is when the subframe bushes go do they bang or click or knock?

[Barx325i]

did you change the rear damper top mounts? also make sure the lower damper bolts are tight.

other than that, give the beam a waggle with a pry bar and see if it's loose enough to make contact with anything.

[mcbonio]

Yep it's got new rear top mounts from an e46 cab. 19mm lower damper bolts are on real tight.

The knock seems to stop for a day when the car has been jacked up, not sure if that's of any relevance. I'm guessing its the subframe bushes as the knock sounds like a tap on the bodywork so I'm guessing its a component that its connected or touches the body.

[kundiboy]

Mine knocked like you say when the beam bushes had collapsed. So it sounds like it.

But get a friendly MOT mechanic to check for play with a pry bar. He will be able to confirm for sure.