What might cause little vibration at 120+ with new tires. car is ford crown vectoria.?

Question

What might cause little vibration at 120+ with new tires. car is ford crown vectoria.?

Answer 1

the car will do 120, seen it myself the vibration is prob a combo of wind, also if u cranking like that make sure you got at least  z rated tires on it.

Answer 2

That would be the driveshaft.

At such speeds, the steel driveshaft does not keep its balance.

Safe motoring.

Answer 3

1.  Tires not properly balanced.  (The typical balance job isn't intended for that kind of speed, nor is the car itself.)

2.  Tires slightly out of round.  (Are you running V-rated tires or better?  Lesser tires are not intended for that speed.)

3.  Brake rotors and/or drums out of balance.  (Again, they are not balanced for that speed.)

4.  Suspension wear.  (EXTREMELY dangerous at those speeds.)

5.  Drive shaft balance.  (Again, the car isn't designed for that speed.)

Note:  Speed observations assume MPH, not KPH.  You should not have any vibration at all at 120 KPH.

Answer 4

What brand tires, some of the cheaper brands have balancing problems.  they can't be balanced because they are out-of-round..  check the weights on them and if any are over 3/4 ounce, take it back.

Answer 5

Assuming before you got new tires there was no vibration.

If that is so, one of the wheels was not balanced properly.  This is important to fix as the new tire may experience uneven wear.  

Speak to your tire seller.  

Answer 6

that car isnt designed to do 120, im surprised it did actually, just the wind resistance can make it vibrate...

Answer 7

I've driven several Crown Victoria's thousands of kms and they have no problem doing 120kms an hr if the tires have all the same thread pattern ,same size , balanced properly and the rims aren't bent , with a solid front end that has had reg alignments done.

Hope that helps and best of luck.By the way if the vehicle handles fine below that speed and you can drive it without it flooding all over the road then chances are you need a 4 wheel alignment performed or a front end part is a tiny bit loose.If you've not had a regular yearly alignment performed then it's highly likely that's the problem , plus any good front end shop won't align the vehicle if they find something slightly loose or that has play in it when it shouldn't have.

Answer 8

It's the driveshaft. Although I always thought that the civilian Crown Vics were governed to 106 MPH for that reason. The Interceptor Crown Vics had a different driveshaft.