2013 DB9 - Steering Rattles and Shimmy at highway speed

[andratch]

Hi Folks, my ‘13 DB9 has had a peculiar steering behavior since I bought it about 4 months ago.

Over larger bumps like railroad tracks, I have a rattle that almost feels like it’s coming from the steering *column*, accompanied by a deeper rattle from the front left or right suspension area outside of the cabin.

The steering itself seems to be heavily influenced by bumps and will shake over a bump. The rattle doesn’t seem to be coming from those air bag shims, it’s deeper back.

I suspected worn control arms, but when pushing them with a pry bar around the bushings, they don’t appear to have excessive movement. When I raise a wheel off the ground, I don’t get any ‘loose bearing’ movement.

I thought the rack bolts might be loose, so I took off the belly pan but it looked secure - I didn’t see a bushing that could be worn on the rack.

I do also get a pretty decent shimmy at highway speeds, but I don’t see any bends in the wheels and they have been road force balanced twice with no change.

I’m curious if anyone has any other ideas of what to check. This isn’t bad enough for me to take it off the road, but it certainly cheapens the driving experience and I’d like to address it.

[Discombobulate]

Tie rod ends?

[andratch]

Not that I can tell, I’m not getting any movement from ball joints when prying.

[GingerMunky]

andratch said:

I do also get a pretty decent shimmy at highway speeds, but I don t see any bends in the wheels and they have been road force balanced twice with no change.

It could be a slight deformation in the wheel, which can be very difficult to see unless it is spinning on one of those tyre changing units and you can hold a pointer to the rim.

I went through 3 sets of balancing and a wheel alignment to find out that there was a 4mm deformation in the alloy which only caused issues above 70-80mph.

Worth double checking as it is the lease expensive of the investigation routes you mentioned.