Getting a slight knocking noise from the left front of my 2012 MCS on takeoff when cold. Checked everything and the only thing I could find is that the front sway bar has about 1/8" sideways play.

The bar has round stops fastened to it (just inside the rubber bar-to-body bushings) that serve as the limits, but there's a little clearance between those and the bushing so the bar can move. If I move it by hand it makes some noise, so maybe that's it? Just wondering if this is normal play or potentially the cause of my noise.

Bushings themselves look and feel okay except for the clearance. If I replaced them it's not clear that the would solve the problem as the inside edge doesn't look worn and the stops on the bar can't be moved. Bar drop link is tight to bar and strut.

 

New bushings.

 

Normally that would be my first step but, like I said, looking at the bushings it's not clear to me that new ones would be any different. There would still be a gap between the ring and the bushing allowing the bar to move.

So given that replacing the bushings is a rather painful drop-the-subframe job, I want to make sure I'm chasing the right thing before I do it.

 

There is no lateral load on that bar, and therefore no need for precision fit.

I'd keep looking...

"on take off, when cold" is an interesting clue. On clutch release? First bump encountered? Just once? A rhythm? Please tell us more....

Cheers,

Charlie

 

Auto box, not manual. Should've included that.

It's basically every time I pull away from a stop: a not too loud knock-knock-knock noise from the left front. It's not really worrying but just kind of annoying. Had a ton of play in the lower control arm bushings and had those replaced with poly but no difference. Motor and transmission mounts all look good.

I suppose it could just be something in the transmission itself, that might explain why it goes away when it warms up.

 

Knock knock knock huh....

Inneresting....

Would that be a wheel speed knock knock knock d'ye reckon??

Cheers,

Charlie

 

Ditto!

I’ve had two Mini’s do this. Weird thing is a worn bushing will only knock a few times and only when dead cold.

 

Fair enough. If that's it I'm just going to live with it for a while, given what a PITA subframe removal is.

 

So I shimmed out the lateral play with a washer I made from some 1/16" polycarbonate stock and it seems to be a lot better. So that's apparently the noise source.

Given that replacing sway bar bushings appears to be a "drop the subframe" job (thanks for the great front suspension design, Mini) I'm gonna call it good until I need to do some other work that requires subframe removal.

Most of the load is vertical, yes, but this being the real world there's often a little sideways load on a sway bar. That's why Mini put the stops on there to limit lateral movement.