When i get up to around 80 mph the car starts shaking/vibrating pretty bad, its mainly the dash and steering wheel and i dont know why. I recently changed the driveshft to the 3in aluminium one thinking it would cure the problem but it didnt, only other thing i can think of is wheels may need to be balanced, any ideas what may be causing this?

 

Could be an wheel alignment/balance problem. Similar thing happend to me last Halloween when I hit a crater dressed up like a pothole. At about 80 it would vibrate like hell and past 100 it was vibrating so fast it pretty much went away. If that's the problem and you don't get it fixed you'll be buying new tires in a month like I did.

 

It's a balance problem more than likely. Wheel alignment will not cause vibrations.

Bring it somewhere reputable and have them rebalance the wheels. If you dont want to spend a lot of money, have just the front two redone. And ask them if they can recalibrate their balancer, if possible. We have an FMC balancer and it only takes about 30 seconds to recalibrate....it's just a matter of knowing HOW.

 

i had the same problem, but it was time 4 new tires anyway, so i put new ones on and it rode like a cloud....just awesome.

 

I agree with the tire balance statement. You didn't say if the brake pedal vibrated as fiercely, but if it does, your problem could actually lie in warped rotors.