Dartmouth

Does you steering wheel have any vibration at higher speeds like over 80? I'm getting it right around 80-85 mph.
I'm wondering if it should be as smooth at those speeds as it is at standard speeds of 50-70 mph. Any comments welcomed.

WhipE350

Likely one of a few things. Bent rim/wheel. This is easiest to determine, just have your local tire store check it. Most can be bent back. Next you could have an alignment issue. Some dealers will do a quick check for a small cost. The last one often not looked at first is inner tie rod. I've owned 7 Porsches three of them with over 50k miles, had one bad tie rod. I would have wasted a ton of money if I hadn't checked first and just gone to get an alignment. I don't know how many times I see folks immediately go for the alignment and their problem doesn't go away.

A lot of folks check front suspension issues by jacking up the car and trying to wiggle the wheel back and forth from side to side or back and forth from top to bottom. I've never found this method to work for an inner tie rod with less than a quarter inch of play. I find the best way to determine this is to pop the out tie rod off the hub and grab the inner tie rod and check if it clicks. Three out of three times I got this right, replaced and THEN got my alignment. Replacing a tie rod is not too hard if you bye the $35 too from Harbor Freight. It is high quality and works great!

Anyway this is my two cents .

SoCal C2S

myw

double check to make sure your
- tires are inflated (tpms sensors would have thrown an error if not)
- all 5 lug bolts are tightened and torqued correctly
- see if there is any glue residue on your wheel if a wheel weight fell off

okbarnett

probably balance issue, but could be any number of worn parts or alignment. Check tire pressure and visual of wheels for bends.
This is what road force balancing is for, to determine balance issues that arent pronounced. Have a knowledgeable road force balance shop diagnosis the problem

Papa Fittig

Most likely and the simplest is balance issue.
Just make sure that you go to a reputable shop to check the balance. It is incredible how many shops around (and some used by Porsche dealers) do not do good work either due to machine issues or even simply not doing proper machine calibration procedures. Don't ask how I know

Petza914

My car is perfectly smooth up to and beyond 125 so you definitely have a issue with vibration at only 85.

Are the wheels OEM or aftermarket. If aftermarket do they have the exactly correct center bore of 71.6mm to marry to the hubcentric flange on the wheel hub? When you remove a wheel from the car and take out all 5 lug bolts, the center bore should lightly still hold it stuck on the hub. If it falls off when the last bolt is removed, the center bore isn't correct. Also if the wheels are aftermarket are you sure you're using the correct lub bolt seat with them. Porsches OEM wheels take a radius or ball seat (rounded profile), but many aftermarket wheels take a conical or tapered seat and if you use a mismatched bolt and wheel seat type, it can allow the wheel to move around on the bolts at higher speeds.

Are you running spacers and if so, are they hubcentric spacers as these are the only kind that should be used. They have a center bore that marries to the hub and then the same size lip on the spacer to center the wheel bore.

loungin

jeffleept

Had similar issue on my last 997. Steering/suspension/wheels cleared by two dealers and an indy. Ended up getting road force balanced again (after one dealership re-balanced) per advice of a colleague on a Hunter GSP 9700, which took away 75% of the problem. Perhaps a bad tire.

Greyghost230

+1 to the Hunter Road Force system.
Just had both summer and winter's done on the weekend. Ask for a Road Force system to balance. The Road Force will run a cylinder up against the tire as it is spinning and applying pressure just as if the tire was on the road.
From this info, the machine can tell if the tire and wheel are not optimally aligned, and can make a recommendation for rotating the tire on the rim. This would require breaking the seal and turning the tire slightly.
I had never seen this before and was quite impressed. I used to balance tires in my brother's shop as a kid, and we didn't have any technology like this.

JABowders

Has your car been sitting for a few months? If so, you might just have flat spotted your tires from sitting stationary. and other than replacing your tires, the way around it is to just drive the car and get the tires through a number of heat cycles to help round them out again. Of course one really good 20 minute stint of a HPDE would work as well...

My cars suffer this because my work occasionally requires me to be out and about and way from my stable, and as much as my neighbor enjoys the opportunity to drive them for me all my cars have suffered this form of tire deformation. But with some time off and a few open roads they generally are corrected in no time once I am home.

Quadcammer

Sorry, as a non-member i cannot offer any assistance

Dartmouth

As a User and not a member I wouldn't want your opinion. Honestly, why are you still here. WE were hoping you had left.

Bruce In Philly

+1 on the Hunter. They can tell you all kinds of things about your rim and tire.... They told me I had bent rims.... read about it here:

https://rennlist.com/forums/997-foru...nstallers.html

If they are a good shop, they will break the tire down and spin it to place heavy spots on the tire opposite heavy spots on the rims. Ask them about this.

Peace
Bruce in Philly

ogun228

No one that I can see picked the simplest and most common cause: worn tires, front or back. Check before anything else.