Steering wheel shakes

[le_the_thriller]

I drive a 1991 g20 automatic; (about 101000 miles) no modifications as of yet -runs great, but feels weak

Well, yesterday I'm driving on the highway at about 85 mph for a short bit and then begin to apply the breaks to come to a stop. As I'm applying the breaks, i noticed how the steering wheel started to shake up and down. This was very noticeable and I seriously doubt that this is normal.
Not long ago a mechanic at PepBoys told me that i might need to replace the motor mounts because hte car 'jumps' when you put it into gear, so i need to get that cleared up quick.

Can this in any way be related to faulty motor mount(s)?

thanks!

[AznVirus]

if you get the shaky steering wheel at high speeds during normal driving, you need a tire balance or wheel alignment. it might be the tires arent gripping the road right, which is in need for a wheel alignment. it might be the mounts, do you hear creaking noises coming from your engine bay when you drive slowly or turning? that is signs of bad mounts.

[le_the_thriller]

No, I don't hear any creaking noises when driving slowly..just the power steering "wheeeze" when I turn sharply. When I was breaking at that speed though, the wheel wasn't vibrating..it was shaking almost violently up and down. Unlike when i put the car into reverse or standing still while in gear, the wheel vibrates quickly up and down (not sure if that's normal either)

[P10DET]

Originally posted by le_the_thriller
I Well, yesterday I'm driving on the highway at about 85 mph for a short bit and then begin to apply the breaks to come to a stop. As I'm applying the breaks, i noticed how the steering wheel started to shake up and down. This was very noticeable and I seriously doubt that this is normal.

Warped rotors.

[jmgladden]

Warped rotors.

I second that. Had the same problem with my Acura Legend a few years ago. Bought some replacement Brembo rotors and it went away.

Buy new rotors, don't let someone talk you into getting them machined. It is a waste and you have the same problem again in no time. Of course you'll need to change the pads at the same time also.

The wheels shaking at high speeds is wheel balance. Bad alignment will cause a pull, bad balance will cause shaking. I have the same problem now, probably because of the shitty factory tires on the car. Don't want to buy new ones cause I'm gonna order my wheels in a few weeks.

Good luck.