Shaking at around 85 mph

[stephendoherty62]

When the car starts to shake a little around 85mph what could be the cause, Tires are not balanced? Alignment not correct? Please advise

[porsche986spyder]

It could be either one of those 2 you just mentioned. Also could be a wheel bearing issue. Hard to tell. Better to just get a free estimate from your machanic. Maybe they can pin point it for you. I would start with the wheels being balanced properly first and then move onto the alignment next and finally the wheel bearing but only if the first 2 did not fix the problem. Those would be in order of cost from low to highest.

[Nick-NY]

it most likley is a wheel balance/bent wheel issue.
bearings will usually make noise at all speeds, increasing with speed.

You may also have a bent wheel, if you take them in for a spin balance they can tell you..

[Grizzly]

Read the TriGem thread and stop going over 85! Kidding. I couldn't resist.

[Brucelee]

Control arm bushings can also do this. How many miles on the car?

[markab986]

ONLY after 85mph?

Free quick checks; missing wheel weights, foreign debris stuck inside the rim, bent rim, tire tread/belt separation, loose lug nuts. (granted this should show up before 85)

Take it in have it checked out, balance, wheels, bearings, suspension, and steering components/alignment...possible driveline component

oh, forgot...front or rear?

[2000SoCalBoxsterS]

Could be lose suspension component, but I bet it's lose Ball joint(s). How many miles on the car?

[chgolatin2]

Have the car checked out by a Porsche tech, doesnt have to be the dealership but get her checked out. Everyone could post their opinions on the thread but nobody knows for sure until someone verifies the info manually and visually.

[FrayAdjacent]

Something is out of balance, or worn...

In this order, this is what I would check:

Wheel balance (check for lost weights, bent rims, abnormal wear on the tires)
Alignment
Tie Rods
Suspension (bushings)
Wheel bearings