
Hoping some of you experienced owners might be able to shed some light on a persistent steering wheel vibration issue I've been battling with my E85 for the past couple of months. It initially started as a noticeable shake around 55mph, only really making its presence known at highway speeds.
Naturally, I jumped into troubleshooting mode to try and nail down the culprit. Here's a rundown of everything I've done so far:
1. Alignment and Bushing Replacement:
My first thought was an alignment issue, so I got a full alignment done. While at it, I also had some worn bushes replaced in the front suspension. This actually seemed to improve things slightly, but a noticeable vibration was still present (and I know Z4s can have a firmer ride, but this felt beyond that).
2. Replaced all my tyres:
These needed a change anyway but with this out the way i confirmed that it's not an imbalance or bulges in the tyres. They're the nice ones too (Michelin & Continental) - I also have the pressure to spec.
3. Wheel Balancing and Buckled Wheel Replacement:
Next up, I had all my wheels balanced. Unfortunately, one of my wheels turned out to be buckled, so I went ahead and replaced it with a new one, which was also balanced. I was really hoping this would be the end of it!
4. Brake Discs Replaced (Separate Issue):
I also noticed a wobble in the steering wheel specifically when braking. To address this, I replaced my brake discs, and thankfully, that particular issue is now resolved.
5. Wheel Refurbishment and Loaner Wheels:
Thinking maybe there was still an issue with my original wheels, I recently had all four of them professionally refurbished and powder-coated. During this time, I had to drive on a set of loaner wheels, and surprisingly, the vibration issue was actually worse with the loaners than with my original setup! After getting my refurbished wheels back and fitted (and presumably balanced again by the tyre shop), the steering wheel vibration is still there. In fact, it now seems to occur across a broader speed range, roughly between 45mph and 70mph, with it being most prominent around 60mph.
6. Bearing and Tie Rod Check:
I even tried to check the wheel bearings myself by giving each wheel a spin and a firm tug, and I didn't notice any abnormal noises or obvious play. Similarly, I had a look at the tie rods, and they seem to be in good condition with no noticeable looseness
So, here I am, still experiencing this frustrating steering wheel vibration, and I'm completely stumped on what the cause could be. I've thrown quite a bit at it already, and the fact that the loaner wheels made it worse is particularly confusing.
Has anyone else experienced a similar persistent vibration after going through these steps? Any thoughts on what I might be missing or what I should investigate next? Any advice or shared experiences would be hugely appreciated as I'm starting to run out of ideas!
Thanks in advance for your help!