I've had a vibration problem with my car and have had the suspension checked a few times. Sounds like you're having the same problem I've had after I got new tires. Here's what I found, maybe it will help........if the place balancing your tires is not very good at it they may be doing it wrong. Because of our wheels they can't put wheel weights on the outsides of the rims, so an inexperienced technician may try to do a static balance. That is typically never good enough to get rid of the vibration - they need to do a dynamic balance using sticky weights near the outside edge of the rim and regular weights on the inside. First go somewhere and have them check your suspension to rule that out - a lot of places will do it free (Sears auto, Belle tire, etc, maybe the dealer). Then go back to the place you got the tires and make sure they do a dynamic balance the way I just described. I've had a problem because of this and I work at the place that did the balancing for me (ridiculous, huh?). I finally figured out what was going wrong and had them do it this way, also using a "high-accuracy" balance mode on the machine (which you might be able to request - or they might not know what you're talking about, depending on the place).