Vibration under acceleration

Mon Mar 17, 2008 2:32 pm

Hi Guys! Just wondering if anyone has experienced the problem I'm having now with my modded 320i.

When accelerating in 2nd gear, I get a slight judder/vibration from the rear at about 3000rpm. This does not occur at any other engine speed, or in any other gear.

The car runs a 3.91 LSD, but it's filled with the correct oil, and has only 40,000 miles on it.

Any ideas?

Richard

Mon Mar 17, 2008 2:52 pm

Prop centre bearing??

Mon Mar 17, 2008 3:07 pm

my guess would be the gearbox if it does not happen at any other gear, the centre bearing would vibrate irregardless of the gear

it could be a worn 2nd gear , the 2nd gear needle bearing, the 2nd gear syncroniser ring or simply the circlip has come loose/dislodged.

to be honest if its a slight vibration it would not be worth fixing due to the complex nature of pulling a gearbox apart.

just leave it unless it gets much worse, the Getrag 260 boxes are normally bullet proof and even a modded 320 would not stress it too much

mrlee

Mon Mar 17, 2008 3:31 pm

That's what I was fearing... I know it's not the prop centre bearing, as this was replaced recently after the clutch was changed. Does the 320i use the 240 'box? I thought it was the 240...

Anyway, I guess I'll just have to put up with the vibration for now.

Mon Mar 17, 2008 3:32 pm

Sorry, I meant: 'Does the 320i use the 260 'box?'...

Mon Mar 17, 2008 5:13 pm

Mind you, this problem occured almost literally over night... I drove it from Swansea to London one weekend -- without vibration. The next weekend, I took it from London to Southend, and that was when I noticed the judder. Could this be something caused by bad fuel?

Without driving the car more on an open road, it's hard to say if the vibration is related to the transmission, or the engine. I've had the diff, clutch and prop bearing replaced. And there had been no juddering after all that work.

I'm stumped...