Vibration starting at 3500 rpm in 5th gear
10-17-2015, 07:13 PM
#1
Intermediate
Thread Starter
Vibration starting at 3500 rpm in 5th gear
I have a 1998 Boxster with 40k miles. I just noticed a vibration, not real bad, starting a 3500 rpm in 5th gear. Can not feel it in any other gear,
10-17-2015, 09:30 PM
#2
Race Director
Could be the tires have worn enough to go out of balance. In this case one only feels the vibration at highway speed and 3500 in 5th is highway speed.
Another possible explanation is a wheel has lost a weight. The tape on weights can come loose if the wheel surface was not properly prepped before applying and if one is a bit injudicious with the water hose or DIY car wash wand.
Wouldn't hurt though to from under the car inspect the car or have it inspected to make sure the engine/transmission mounts are OK, along with the CV joints (and the dust boots are intact).
How's tire wear? Depending upon what you see alignment could be off. But tire imbalance is the more common cause. But tire inflation pressures should be checked and corrected. Just a few PSI overinflation of the front tires caused my 2002 Boxster to manifest a vibration at highway speed.