Tires need to be rebalanced?

[89_3SFE]

I took my 89 Celica GT to Firestone to get an oil change and I also got the tires rotated and balanced. Well, later that night I replaced the brake rotor on the front, drivers-side wheel because it was making a humming noise and needed to be replaced. I noticed that the steering wheel would rock back and forth if I was accelerating under about 30 mph. Well, I don't think it's the brakes because the brakes work great now and the steering wheel rocked back and forth when I took it off the lot at firestone.

I also just took it on a little 4-hour trip for the 4th of July and noticed that the car would vibrate a little when i was driving around 80 mph. Do you guys think that's just an imbalanced tire and that I should just take it back to firestone to do it, or could it be something worse? Thanks for your help guys!

[flex-appeal]

yeah sounds like a tyre is out of balance, make them sort it out for you. Its possible that when they balanced the tyre, one of the weights wasnt clipped on right.
Are the tyres directional? Make sure they are going the right way...

[EggBeater59]

it may seem silly, but check your lug nuts. make sure they're completely tightened and not on backwards.