SwissHHR

I have had this lateral wobbling for quite some time now. It only seems to occur when accelerating fast or driving uphill, going straight on, mostly noticeably in fourth gear. It seems to vanish when driving through a curve. It goes away when slowing down. It occurs with both summer wheels (steel) and winter wheels (aluminium). It doesn't occur when just cruising (no acceleration). It feels like the car is shaking/wobbling/shuddering sideways under load. The wobbling has not gotten worse over time.

When did the wobbling start? It may be a coincidence, but it first seem to start to occur after I had to have an alignment done after having hit an aluminium pipe with the back of the front left wheel backing the car slowly out of a parking space in reverse gear (see diagram below). After the hit the car pulled pronouncedly to the right, hence the alignment. Nothing else was visibly damaged. Since the alignment the car goes perfectly straight again (as it did before the hit).

-> There definitely was no wobbling before I hit the pipe.
-> I am pretty sure that there was no wobbling during the time period between the hit and the alignment.
-> The wobbling seemed to start to occur after the alignment and hasn’t’ vanished since, but also did not get worse.

Here’s what I have replaced since the hit for other reasons:
- KYB Front Excel-G struts
- MOOG strut mounts and insulators
- ACDelco lower control arms 45D2486 and 45D2487
- GM swaybar bushings (20902784) and Dorman two-hole brackets (928319)

None of these parts had any impact on the wobbling, for better or worse.

Any ideas or theory about this wobbling? Could it be that because of the hit, some part was bent or shifted and started to cause the wobbling AFTER the alignment?

Cat Man HHR

I just looked up the lower control arm from Rock Auto for the SS. I come up with ACDelco #25930725. The site doesn't list the part numbers you gave.
https://www.rockauto.com/en/catalog/...trol+arm,10401
I found this about the Toe. Was yours adjusted correctly?

donbrew

Hubs.

firemangeorge

I would also check the engine and transmission mounts. If you hit that post hard enough to knock out the alignment, it could have been enough to damage one or more of the mounts.

Oldblue

Cat Man HHR

Sorry for the mistake Blue.

Oldblue

SwissHHR

Thanks for all the input. I was afraid that it is not something easy to locate...

I think we can rule out the wheels as it happens with both the summer and the winter wheels. I hit the post with the winter wheels.

- As for the Toe: I would have to ask the workshop where the alignment was done. Are there any recommended values for toe?
- Not long before I hit the post, I had new hubs installed (Timken). What might be a good way to check them (short of replacing them right away)?
- To add more possible candidats: what about the steering shaft or drive shafts?

firemangeorge

Oldblue