I've got a weird wheel shake I'm hoping you guys can help with. It occurs only while it is raining. The shake is significant (as though the wheel(s) were way out of balance). After the car has dried it returns to normal and runs straight and true. The shake occurs from about 75 - 85 mph.

The car was aligned and all 4 wheels balanced but the condition continues. I run 19" wheels. (no need to get into the merits of 19s or 18s please). Has anyone heard of 19s throwing off the PSM or any other controls that might cause this.

Any thoughts appreciated, thanks

 

Would it be possible that your wheels are trapping water and throw off the balance? I had use a fix-a-flat before (not on a Pcar) and it threw off the balance.

 

Thanks MY996TT

The wheels are wide. 12' in back 10" in front. 4" dish in back, 2" dish in front. I've never heard of wheels collecting water (espcially) at +/- 80 mph.

Is this possible? Can anyone confirm?

 

I used to have a set of HRE's on my audi that had a reverse lip, which caused water to build up and vibrate the wheel. I don't think there was anything you could do about it??

 

Intermittent hydroplaning? The wheels are quite wide - how big are the tires, and what kind are they?

 

Read this as well- certain profiles will not drain water from the wheel 'barrel' and at speed water trapped in here creates an unequal weight and vibrates.

Why ya driving in the rain, anyways? (jk)

What model rim?

A

 

I have HRE's and I get significant wheel shake in the rain. Thankfully it doesn't rain very much here in Phoenix.

 

From what i understand HRE's, due to their reverse lip design, collect water within the lip during rain and only around the speed you indicated (70+) there is significant shaking, i would think other wheels besides HRE's would cause this problem

 

HRE's are famous for that issue.

 

most 3 pc wheels have the same issues.

 

I have HRE, but I don't have the reverse lips and don't know if the wheels have the same issue. But then, my car only saw rain once... the day I pick her up.

 

My wheels are Avus AF-M02, they are 3 piece. Avus Known primarily for F1 wheels (good article here http://www.europeancarweb.com/tech/e...els/index.html )

The wheels look like this. http://wheelsperformancecom.stores.y...avusrfmo2.html

Avus North America went belly up in Jan 2008 and are still looking for a new US distributor.

Tires are Conti Sport Contact 2, 255/30 - 19 and 315/25 - 19. I have about 60% tread life left.

I hadn't heard of hydroplanning causing whell shake, but interesting that other wide lipped wheels have caused that same condition.

Thanks for the responses.

 

The issue of water collecting in the wheel well and causing the symptoms described by the OP is known. It is not, however, due to the manufacturer, but the design of the reverse lip 3-piece wheel.

see here

 

wross996TT thanks for the thread lead, I missed it in my search. There is a discussion in that thread regarding "reverse lip wheels that have a channel in the back drum". See below.



My wheels don't have that "channel". I don't think that back drum on a reverse lipped wheel is deeper than an OEM wheel. Does water collect in the outside lip?

 

Virtually all 3-piece reverse mount wheels suffer from vibration caused by water retention. Reverse mount wheels require that the drop center for tire mounting be in the inner barrel.
In heavy rain, the water collects in this groove and cannot escape because of centrifugal force. There are a variety of "water dams" that you can mount in the groove that reduce the problem, but not eliminate it.
This problem has nothing to do with hydroplaning.