High Speed Vibration:
 

Wife told me her 2007 Equinox was making a vibrating feeling when she got between 75-80mph on the hwy, jokingly I stated to slow down however I drove it the other day and it did just as she stated, vibrating feeling at the speeds listed above, 53k miles on it and I know we need to get the tires rotated, so has anyone heard of or experienced this issue and if so, can you elaborate on what the issue may be?

yes check the carrier bearing 1st.. if not that its prolly your basic tires needing rebalanced or also check the sticker in the door to see what size tires it is suppose to have and see what size are ont it.. if there the same size that wer on my girls car they jus barly clear the front struts so when u get going that fast the tires swell up and may rub..

could be ball joints..nythign over 65 in my truck it would vibrate and bounce.

I've also had a car shake because of snow or mud packed up underneith! Just checking the obvious first because it can happen!

Thanks all for the replies, I will look into it,

So, what am I looking for as far as the carrier bearing or Ball joint
Play within the two or what?