[wepio]

Hopefully someone can explain this to me...

I've noticed my steering wheel twitches whenever I'm going at high speed through long curves (2x recommended speed for cloverleaf freeway interchanges). It's not a constant vibration, but feels like a sudden twitch or jerk in the steering wheel. Is it sidewall buckling? My warranty expires next month, so if it's a mechanical issue with the car, I'd want it taken care of on BMW's dime.

I have PSS's on OEM 18's, and active steering. 36k miles.

Thanks!

[smallseafishie]

How many miles are on it? I had a similar issue on an older car where the control arm bushing were worn.

[wepio]

It's a 2009, with 36k miles. I can't remember if I noticed it with the RFT's. But, it is definitely noticeable with the PSS's.

[smallseafishie]

I'm running PSS's with no issues. My turn in is actually really predictable and a highlight for these tires. Maybe you need an alignment? 36k miles is too early for worn bushings. Has it ever been wrecked or have you bent a wheel or something pothole related that could affect your suspension? I don't have any personal experience with active steering so I can't comment in that aspect.

[wepio]

The car hasn't been wrecked. I had the car aligned at the same time the PSS's were installed, which was ~5k miles ago. The alignment shop did say the front wheels are bent, but not to any detrimental affect on mechanics/performance, which I specifically asked about; only compromise is in ride quality.

The twitch doesn't occur on hard 90° turns, like in-town right/left. Maybe I'll have an indie shop look over the entire car before the warranty expires.

[smallseafishie]

Does active steering require specialized alignment? I remember the dealership charging more for it... Something along the lines of having the steering rack put in some special mode prior to the alignment... Did you have it done at the dealership?

[wepio]

I'm not sure if Active Steering requires any special preparation. I had the alignment and tire installation done at TruLine of Bellevue, Washington, and informed them of Active Steering.

This is just odd. Maybe I'll grab a service tech and have them rip through some curves. I don't know if you can feel it through the car, or only through the steering wheel. Because it's so pronounced through the steering wheel, it detracts from being able to notice if it's felt throughout the car.

[gaza01]

A worn bush somewhere?

[smallseafishie]

Do some searches. It looks like active steering requires special alginment.

[wepio]

Originally Posted by gaza01

A worn bush somewhere?

Took it to BMW. They said the front tension struts are bent, and also commented on the bent front wheels. The SA will try to get it covered under warranty, but won't find out until tomorrow.

Originally Posted by smallseafishie

Do some searches. It looks like active steering requires special alginment.

Yeah, you're right. Active steering does require special calibration, but from what I can tell, nothing special about the actual alignment process. The calibration is to sync the adaptive headlights to the steering sensors.