Prius shaking at highway speeds

I would check the alignment, like you suggested. Are all the tires up to pressure?

 

Are your wheels balanced? You might want to check that as well.

 

My money says it's a wheel out of balance. I've had this in the past: shaking would occur only at a particular speed, such as 48 MPH. Slow down or speed up, it goes away either way.

Do you remember hitting a curb somewhat hard? Are you the only driver of the car? If not, would the other driver(s) tell you if they had hit a curb? Sometimes people hit curbs hard enough to throw a wheel out of balance and don't give it a second thought.

Any tire place will put each wheel on a dynamometer and spin it up to the equivalent of about 100 MPH. If it's out of whack, the light will show it at any point where it occurs. (Sometimes it can be seen with the naked eye.)

I've also had it happen where the vibration/shaking occurs at TWO different speeds. Or it can occur dramatically at one speed, then taper off to "barely detectable" as you speed up.

Good luck.

 

What about cross wind's? If it was balanced and aligned it would be at the same speed, you said "The vibration is an on and off thing. Sometimes, I get it and sometime not, even at the same speed."
So I'm wondering about strong cross winds or around big vehicles or big rigs?

 

Since it has been doing it for a month now, the tire would very likely show damage at this point.

Look for uneven wear, like a spot that is starting to bald. That is a dead giveaway of a tire in desperate need of balancing.

 

Scotty and Ghost have hit the buzzer. You threw a front wheel balancing weight. Or maybe there is a big chunk of mud on the inside of the wheel where folks would not normally look.

Good on you for noticing. Now do the right thing.

 

i just brought a 2011 leftover prius..not the plug in...it started vibrating at highway speeds....first day ....twice in one day it happened...brand new car....what the h.....

 

As others have written:
- check tire pressures are even
- check the tires for stones, dirt or damage that would make them roll uneven
- if you can't resolve it take it back to the dealer, describe the problem and tell them to fix it. No, it's not "normal behavior".

 

thanks, i did check the tire pressure...everything looks good...

 

mine doesn't shake but is sometimes hard to control because of crosswinds. suggestions.

VM670 ?

 

Get thee to the dealer right away, might be something dangerous. If I had to guess, it would be a defective out of round tire, happens more often that you would think.