I was riding down I-85 lastnight. I usually drive at 55MPH bc. This time I was in a hurry and was driving at about 65-70 mph. They car was swaying a lot. Why was it doing this? Any suggestions. I know I need an alignment. Could this be the issue. I don't feel the sway at all when I riding at around 55.

55 MPH just try taking it up to 80 mph it should stop 50 55 whats up with that you have fiero (I cant drive 55) swaying when was the last time you checked the shocks and springs ? I do not think it would be the wheel alignment.the wheel alignment would make the car shake and pull to one side. Eddie

Get the alignment done. that could easily do this. could also be soft bushings or worn joint(s) some place.

Could be rear tire pressure.

Check for worn or missing bushings. also worn shocks and struts on a fiero are difficult sometimes to tell if they are worn out until they ar removed, then it is very obvious. I have had suspenshion that felt fine but when the shocks for example were removed and compressed went down and stayed down for the count.

Do you have really wide tires in front? Wide tires will "hunt" as they follow every groove in the road.

One of our local club members had that problem. We put my narrower tires (205's) on his front as a test and the problem went away.

I also agree that too high a tire pressure will cause the car to drift.

I have also had a strut on the passenger side blow a seal. Nothing is more creepy than having a dead strut on one corner at any speed puts the cars handling way out of wack...

Floaty isn't bad;twitchy is.
I'd just drive at a speed that you're comfortable with,as this is,or can be caused by a bunch of things that wear out on older cars like wheel bearings,shocks,tire wear,as well as some things that came from the factory as well,like aero-lift,grandma springs,bicycle tires.

My (daughters) 87SE was real ?? Floaty, but I knew the tires were BAD OWWww BAD DAD.
Anyway Newer tires fixed it up??
Now!! think of the conditions??? You were in??? Here in KANSAS, WIND WIND and more Wind do make a difference??? I know you are saying our cars are too short to be effected by that, but they are??? Next time you fly by an 18 wheeler, (just ask the Monkeyman) try and tell me you can't feel it??
But my guess would be tires and/or alignment!!

Thanks for the info guys. I just check the tires and they have good tread but check this.

Front Tires
205 65 15

Rear Tires
Driver rear - 225 60 15
Pass rear - 215 50 15

I thought that passenger rear looked kinda small in the wheelwell I didn't notice them when I first bought the car a couple of months ago.

These tires are on my stock rims from my 86 GT.

I have new 225 60 14s all the way around and my car tends to "hunt" as well. Once i start a lane change it seems to finish it up automatically, like it knew where to go.

My 84 SE had the same problem a while back... before i blew the engine.. it was ok until u got around 55-60 mph... and i had new tires.... i put new struts, and hub assemblies (wheel bearing assembly) on the rear and it fixed the prob...

chris

I have 215/60-15 Rs on the front and it hunts

3 different sizes! Oh man!

We had a GT come into the shop with stock wheels but we kept thinking it looked odd...it seemed to be leaning. We checked the sizes and he had the 205s on the passengers side and the 215s on the drivers side. Guess who had their tires rotated!

I used to run 225/50R16 BFGoodrich Comp TA VR4 and they wouldnt hunt unless there was a serious seam in the roadway. Right now I run more tame H rated Auroras without any problems.

I had the same problem with my '87. I replaced the front and rear bushings with urethane, installed junkyard GT springs and new struts & shocks.I already had GT 15x7 wheels with 225-60-15's. An alignment helped but a huge improvement came from switching to junkyard '93 GrandAm 16" directional rims with 205-55-16's.They even say "pontiac" on one spoke. They have more backspacing and dont extend out as far so it doesnt look quite right from the rear but it looks great from the side(especially for $60/each with almost new Goodyears mounted). I did have to buy one tire from Pep Boys for $42(50,000 mile Futura). To replace my 225-60's would have cost me $57/each. If I had a digital cam I'd throw up a pic.