Wheel Balancing

After the first 30 miles in my cayman it was fairly obvious that there was some shaking in the steering wheel and a little vibration that felt like the wheels just werent balanced properly. I took it back to the dealership and they took a look, messed with it (not sure if they did anything at all actually) and said, it should be fine. well...it did feel a little better, not perfect but driveable. I have had the wheels taken off a couple of times since then at GMP where they worked on the fitment for other wheels. After my stock wheels got on again i noticed the same shaking and vibration...so i took it back to GMP and they rebalanced the wheels, said they were only off by a hair. So....now the shaking is less noticeable and the vibration is bearable, but if i let go of the steering wheel at 45mph, i get some shaking. is anyone else having this issue? my audi was smooth as silk, but my saab used to give me headaches just like this... any ideas? /fckeditor/editor/images/smiley/MWPX/confused_smile.gif

I have been in the wheel and tire business for 25 years. Although I currently do not do anything with automobile or truck tires (strictly OEM to trailer manufacturers) I have had a lot of experience. I also have had significant problems with ride disturbance issues on a Boxster . I was probably attempting to put an incompatible mix together on the Boxster . My Cayman is as smooth as silk with the 19' sport design wheels. But, all this being said, you really need to take your car to a tire store that specializes in high performance product. You should have them road force balanced on Hunter equipment. This will both provide as near perfect balance as possible and will also tell you if you have any problems with either wheel or tire in concentricity or weight. Given the quality of the stock wheels and tires that Porsche uses I am confident that it is a balance issue and not a defective product. Obviously, this is only my opinion and as such may not be worth much.

hey tim, thanks for the advice. I will check around today for a shop in my area that can do it.

"My Cayman is as smooth as silk with the 19" sport design wheels." Glad to hear the SD wheels seem smooth for you. RedRocket - I hope the Cayman S wheels will balance up right for you, I'm still thinking about getting a second set of 18" Cayman S wheels at some point, and mostly it seems I have heard only good reports about them.

RedRocket, Remember they changed your suspension, had wheels on and off several times. If your wheels/tires balance out via a road force balance machine then the remaining culprit could be something involved with your suspension change. FWIW I have no such shaking in my stock 18's set up. If the problem wasn't there when you first got your car, then it is a result of some change you've made to it, since multiple changes have been made, it may be a little hard to say exactly what the cause is until you start ruling things out one by one.

See if you can find a shop with a Hunter Road Force balancer. Actually, I believe Porsche of NA requires that machine at the dealerships. This link could help you locate one. -Pete http://www.gsp9700.com/pub/search/findgsp9700.cfm Edited by - stratmosphere on 02/28/2006 11:28:04 AM

i am probably gonna take it back to the dealership again. K-Man S, the problem was definitely there before I had the car dropped and to the same extent pretty much. In my experience with lowering other cars, it never affected wheel vibration. i guess it is possible the the tires or wheels were damaged while removing them from the car, but because it was an issue prior to that I am gonna take it back to porsche and make sure they look at every possible option. the vibration although annoying is not extreme by any means, just a small gremlin that needs to get worked out.

I checked the website and the porsche dealership doesnt show up on it, so after i call to verify, i will either be taking it to porsche or a dealer or shop on the list.....thanks for the link!

Could those 15mm spacers have any impact?

The 15mm spacers will magnify any imbalance in the car by creating a longer torque arm and thus greater force, but I think he said that the problem was there before he lowered the car and added spacers. A Hunter machine is a good place to start with respect to tire/wheel roundness and balance.

i am headed over to a nissan dealership here in myrtle beach this morning to get my wheels 'fixed' i hope. the trip down although fun, was slightly agrivating with the steering wheels giving me the shakes occasionally. one of the tire shops in the area that uses hunter equipment said they couldnt do my porsche ...not sure why...hopefully my luck will be better with nissan. they have some other thing by hunter that is supposed to help with steering wheel pull as well, without an alignment. anyway...wish me luck...ill give my results later...

ok.......nissan guys did a roadforce balance on a hunter machine.....no luck. i mean..they said they got everything right, but they also noticed some wheel shake between 55 and 75mph. so, i called porsche . the guy in the service dept. seemed concerned and told me to definitely bring it in on monday so they can peice together what is going on. i was really impressed with his attitude and the concern he seemed to have over the situation. i made it back from myrtle beach without incident, but i cant wait to drive my cayman without the shaking. i think its a bad set of tires myself, my wife ran into the same thing several years ago with the tires on her pathfinder. we will see.....and the saga continues. updates to follow...../fckeditor/editor/images/smiley/MWPX/confused_smile.gif

RedRocket, what did your Porsche service department conclude about the wheel shake?

going in on friday to let them take a look....ill let you know.

RedRocket, what was the solution? Or is it not fixed?

i took my cayman back to the dealer and had them take another look......they took one of the tires off the wheel and rotated it slightly and filled it back with air and balanced.....unbelievably...it drives smooth as silk. i almost didnt believe it. i called the service guy back 10 minutes later as i was cruising down the expressway at 80mph with absolutely no vibration at all and thanked him over, and over, and over again. ive got a 1200 mile trip coming up later this week and we will see how she drives the distance. im hoping everything stays nice and tight.

Thanks man. I have a slight problem that I need to see if I can get fixed as well. Not too bad but at 65-70 it has a bit of a shimmy. Over that no problems.

This wheel shimmy seems to be more than an isolated incident. My car (250 miles on the clock) goes in on Wednesday. My dealer does use a GPS9700 balancer, which is the best available. I used to take my hot rod MCoupe to the Porsche dealer for all wheel balance work before I bought a car from them. I'll suggest that they spin the tire on the rim.