Planet-9 Porsche Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
25 Posts
Discussion Starter · #1 ·
Hello, I have a steering wheel vibration at 55-60mph and higher. The wheels/tires have been balanced, and the issue still exists? My mechanic took a look at the suspension and didn't notice any issues? Any idea what could be causing this? Could it be rust on a rotor?

Thanks
 

·
Premium Member
Joined
·
805 Posts
It COULD but I expect you need to readdress the balance and runout of the wheels and tires. Try bedding the brakes well until the rotors are nice and shiny though.
 

·
Registered
Joined
·
40 Posts
Have you checked the tires for flat spots? I had a set of Conti ExtremeContact DW that had a flat spot on one of them, drove the shop CRAZY until they checked them for being round, they replaced at no charge...

Still like the DW a lot (the price can't be beat)!
 

·
Registered
Joined
·
135 Posts
Have you checked the tires for flat spots? I had a set of Conti ExtremeContact DW that had a flat spot on one of them, drove the shop CRAZY until they checked them for being round, they replaced at no charge...

Still like the DW a lot (the price can't be beat)!
Agree. I found an installer that had a "Road Force" balance machine. With my last set of rear tires ordered online, the installer rejected 3 tires that were out of round before receiving two that were within spec. Extra cost of shipping and labor for mounting/balancing (except weights) were refunded.
 

·
Registered
Joined
·
1,719 Posts
Not sure, but I found all my cars started to do that as they got older. Sometimes it was just that the road was bump (looks flat sitting in the car, but if you got out and looked at the pavement, you'd see small frequent waves). I'd see if it does it on all roads.
 

·
Registered
Joined
·
21 Posts
While I dont think steering wheel excessive shake is normal, try to remember that these cars have great road feel. So any inconsistencies in the tarmac will be felt through the wheel. I have found driving on different surfaces changes the shake considerably from none to moderate at 60-75 mph.

I would check the front tires by taking them off and running a hand over the tread to check for flat spots, then I'd check the wheels inside and out for damage (bent wheels will cause vibration). If thats ok and the car has been sitting, especially in the cold, take it for a long drive and see if the problem goes away. If it doesnt, try to rebalance on the hunter machines.
There is a lot you can do before you take the car somewhere and drop your cash. Plenty of people have done that and their problem remained
 

·
Registered
Joined
·
3 Posts
Take a close look at front suspension bushings. As the materials wears it can cause shake especially when braking which feels exactly like warped rotors, but isn't.
 

·
Registered
Joined
·
48 Posts
Have someone who knows what they are doing check the front 2 wheel/tire assemblies to make sure they are balanced, PROPERLY. I am 99% sure this is your issue.

Dynamic plane, with no cross balancing, proper wheel OD/ID measurements (machine), and no errant weights left on the wheel opposite one another etc (trust me I've seen it all). Make sure everything reads 0 oz on both planes when finished. If the balancing machine is calling for more than 3oz anywhere I would break the bead of the tire, mark its relation to the wheel with a line, and rotate it 180* degrees on the wheel surface. Air the tire back up, and try balancing again. Sometimes tires aren't perfectly uniform (although they appear to be), and changing their location relative to the wheel can play a part in reducing mass needed to bring the assembly in balance.

While on the balancer, I would watch the inner lip of the wheel as it rotates to make sure there is no slight wobling or movement off the centerline--which would indicate that the wheel is bent (from impact). You CAN balance out a bent wheel/tire assembly to zero, and still feel vibration at speed. Then i would move to checking the tires for "chop". Run your hand over the tire surface in the direction of tire rotation, it should feel smooth with no ridging or bumpiness. If it is not, you can bet your alignment is off, and/or the tire has flat spotting from non-abs braking. Tire "chop" will cause steering wheel vibration even if the assembly is balanced properly.

Lastly, if those things pan out, like others said, look at suspension components and bushings (tie rods especially). However, given that you say this is a problem that appears at certain speeds, all signs point to an unbalanced rotating mass.
 

·
Registered
Joined
·
1,259 Posts
You should ask your shop to calibrate the road force balancing machine before they check your wheel balance.
 

·
Registered
Joined
·
832 Posts
Hello, I have a steering wheel vibration at 55-60mph and higher. The wheels/tires have been balanced, and the issue still exists? My mechanic took a look at the suspension and didn't notice any issues? Any idea what could be causing this? Could it be rust on a rotor?

Thanks
The Titanic doesn't have that much rust.

Really, unless you feel a pulsing when you use the brakes the brakes have (probably) nothing to do with this symptom.

If the behavior came on all the sudden suspect a weight went missing. Also, check tire pressures. I have found with my Boxster overinflated -- but just a few PSI -- front tires can cause a vibration that is as near as I can tell indistinguishable from a wheel/tire imbalance.

If the symptom kind of snuck up on you gradually what can happen is as the tires wear they can go out of balance. For the last few sets of tires, whenever I replace the rear tires -- with the fronts half worn -- the fronts are out of balance and I get them rebalanced. The same for my Turbo.

Feel the tire tread. If you feel feathering or roughness this can be a sign of the tires being out of alignment.

I have to caution you that you have to really trust the shop that it will balance the wheels/tires or even if you decide the problem is an alignment that it really aligns the car. Be sure you ask for and get a *before* and *after* print out of the wheel/tire alignment settings. There has been at least one case where the owner chased a problem that eventually proved to be a balance problem but he only found this out when he used another shop and it really balanced the wheels/tires.

If balance or tire inflation not the solution be sure you arrange to have the car's suspension/steering checked out. While it is rare one just goes bad a bushing/component failure can cause problems.
 
1 - 13 of 13 Posts
Top