Grand Am tech question

[darkred87T]

I guess I could go on the Grand Am forum but I think there is alot more knowlege in general about cars in this forum.

I have a 2001 Pontiac Grand AM and it shakes like crazy on the highway. I noticed today that the outside edge of the left front tire is wearing severly. I jacked it up tonight but couldn't duplicate the problem. Any guesses about what it might be?

I'm guessing it needs a ball joint but could it be a strut bearing or the strut itself? It looks like a pretty simple set up. I recently replaced a tie rod end on the other side but this is a totally new symptom.

I'm trying to avoid bringing somewhere as it will probably only be guess work there as well and I don't want to get charged for a whole new front end.

Thanks in advance for any advice,

Mike

[kh440]

I seem to recall the Malibu (same chassis) having issues with the strut plates/bearings. Think there was a TSB about it but I can't swear to that.

[gunslinger]

If the outside edge is wearing that badly, you've either got something bent (strut, or knuckle) or you've got a separated tire.

If you hit anything hard enough to bend something in the front end, you'd remember it, so I'd be taking a close look at the tire. Take it to a good tire shop (not one of those national chains) and have them check it out for you.

[SRGN]

Originally Posted by gunslinger

If the outside edge is wearing that badly, you've either got something bent (strut, or knuckle) or you've got a separated tire.

I agree.

[Madcat455]

a seperated tire would be felt at almost all speeds...

I agree with a strut bearing, or wheel hub... both are common issues with these cars.

My 2000 ALero has a bad vib when braking from hwy speeds only. Probably the beginning of a strut bearing.

[gunslinger]

Originally Posted by Madcat455

a seperated tire would be felt at almost all speeds...

I agree with a strut bearing, or wheel hub... both are common issues with these cars.

My 2000 ALero has a bad vib when braking from hwy speeds only. Probably the beginning of a strut bearing.

Depends how bad the separation is.

A bad strut mount bearing will NOT cause a vibration....memory steer, pull, noise, eventually broken springs...but not a vibration.

Wheel hub, maybe...but it would be noisy well before that, and would have to have quite a bit of play.

[Madcat455]

Originally Posted by gunslinger

Depends how bad the separation is.

A bad strut mount bearing will NOT cause a vibration....memory steer, pull, noise, eventually broken springs...but not a vibration.

Wheel hub, maybe...but it would be noisy well before that, and would have to have quite a bit of play.

I've been in a grand am that did exactly that... any speed over 45, as long as it was good pavement it'd be fine, but hit a bump, steer, shift the weight of the car in any way, and the wheel wouldn't stop shaking until you slowed way down.

Replaced strut mounts, problem solved

My 2000 Alero is the same way that GA was, only when braking from speeds 60+... anything lower and it stops smooth as silk, but try hitting the brake above 60 and you better be holding that wheel tightly.

Had 4 different mech. shops(looking for best price) confirm bad strut mounts, haven't bothered to replace them yet

I only mentioned the hubs because they're known issues on these cars... I agree that he would've probably noticed other signs long before it got bad enough to shake.

[TTA81]

If the car is shaking badly only when braking from 60+, I know for a fact it is the brake rotors. This is talked about a gazillion times on grandamgt.com

If you still have the original rotors on there, they are junk. I believe there is a TSB on this for these cars. My 2000 GA did the same thing when it had about 20K miles on it and the dealer replaced it with a new "improved" version and to this day (124K mi) no violent shaking while braking.

HTH

[Madcat455]

Originally Posted by TTA81

If the car is shaking badly only when braking from 60+, I know for a fact it is the brake rotors. This is talked about a gazillion times on grandamgt.com

If you still have the original rotors on there, they are junk. I believe there is a TSB on this for these cars. My 2000 GA did the same thing when it had about 20K miles on it and the dealer replaced it with a new "improved" version and to this day (124K mi) no violent shaking while braking.

HTH

Rotors were replaced @ 55K..... car only has 70K on it Maybe I'll change them anyway, not like they're expensive..lol.

I'll never own another one of these body cars again.

[usetaboost]

Most probable cause would be tire, but COULD be bad strut mount. Worked in a tire shop for 4 years, even seen new tires do this. I've seen them separate all around just like you've described. If you yourself can't see the height variance from the broken belt take it to a tire shop and have them spin it on a balancer and watch for a bad tire or bent wheel. Bad tires can cause a lot of problems, kinda like a transmission being low on fluid. If it isn't the tire then have the suspension checked and have the alignment looked at to see if you have anything bent-If you are way outta spec that will tell you right there. Hell if there was front suspension parts that were that bad I guarantee you could duplicate them if you knew half of what you should. Our 99 grand am has almost 140k on her and still going strong. Everything works except for the stupid light in the stereo. All I've done to it is 2 outers, full tune up, radiator cap, front brakes and rotors, upper hose, battery, water pump, serp belt and tensioner, alignment and currently on it's third set of tires (originals included).
A few of those things weren't in need but I did them cause we were going on a 4 hour trip out in no man's land Yes they are common like ford tempos and escorts, but at least I'm not embarrased to drive it to my friends' house Oh, no oil or transmission leaks either

[darkred87T]

Thanks for the replies.

It's been a great little car since Iv'e owned it. I haven't had any major problems with it up until this point and I keep a pretty close eye on things.

I took it to work yesterday and it was shaking pretty badly at around 70MPH. That's when it became apparent to me that something was wrong. When I parked it, I checked out the tire and found the outside tread was worn down.

The roads get pretty nasty in some parts of my commute. I hit some pretty bad pot holes sometimes but I usually don't think much of it. It never crossed my mind that I might have bent somenthing. The control arms are pressed steel.

I have a ball joint on order from my local auto parts store. For $46 bucks and a little bit of my own labor it's worth a shot.

[usetaboost]

If it were me and I had trouble with this problem I would take it to an independantly owned shop and have it looked at. I wouldn't go wasting money throwing parts at it. If they charge you 25 bucks to look at it, it's still cheaper than wasting time and money installing a ball joint that you haven't been able to find anything wrong with. Hell my old camaro had blown struts, busted springs, tie rod ends that were so bad I was told not to drive it to work again until I got them replaced, and you'd never know it going 100 mph down the interstate . Don't waste your money, start with the rim and tire and go there. You DID get an alignment done when you replaced the tie rod, right?