Hi all, being an old timer I usually know just about everything about my old 55 but this one has me stumped.

I have 90k on my stock wheels and fairly new rotors. I have a true vibration in the steering wheel at 22MPH. None before and slowly goes away at 27MPH. It feels high frequency and the tires are balanced perfectly x 2
. It feels like it might be a harmonic associated with the slotted disks. Has anyone ever heard of this?

Thanks for the suggestions

My passenger seat still vibrates on the freeway... not as much as with stock rims vs 19" CLS rims.

My stock rims are probably a bit bent, but I do have brand new hankooks.

I don't remember a time my E55 was perfect without some vibration.

vibration at 27mph is ok. Vibration at 80mph drives me nuts.

That's why my 19s are off and won't be going back on.

I got a second opinion from a the local shop and found that there is a wear pattern on the inside tires and have a slight scalloping which was giving a whirring vibration best felt thru the steering wheel. Everything else checked out OK.
Well I guess I'll go ahead and replace the rear PS2s too, they'll be gone in less than a 2000 miles anyway. I drive it like I stole it.