This guy pulled up next to me an said my left rear passanger tire appears to have a little wobble.

I immediately thought my lugs for some reason were loose. I pulled over and checked the lugs, but they were tight.

What could cause such a wobble if the wheel is on tight? Bent Rim? Or, I purchased some used tires from Discount Tire to put on the car since it is driven very little around town because its main duty will be for the road course. Do you think it could be this tire?

Ideas?

Thanks

 

You mean right rear? Anyway, I'd take the wheel off and roll it in the driveway to see if the tire is out-of-round. The rim could be bent but then they should have caught that when the tires were balanced. The other possibility is a bent axle shaft. But if you haven't hit anything, it shouldn't be that.