Tires: 2001 Honda Civic Coupetires?, honda civic coupe, road irregularities

Question

Hello Mr. Smith

I currently am experienceing difficulty with my 2001 honda civic wearing Firestone fr 690S.

The symptoms include: a low frequecy, cyclical shudder or side to side shimmy when the brakes are applied at in town driving speeds. This shimmy is directly relational to the speed of the vehicle as the frequency drops when the vehicle slows.
Secondly there is a serious vibration in the front end of the vehicle when the brakes are applied aggressively at highway speeds.
While driving the car at either highway or normal town speeds however, there is neither noise nor any perceivable  vibration.The shimmy occurs only under braking.
The tires have been rotated regularly and the pressures are checked and corrected weekly.
On the occasion of taking the car to the dealer to have the situation corrected I was assured that the problem was with the tires or simply vibration due to road irregularities. This explanation seems insufficient to me. In the 20 years I have been driving and working on cars I have driven and owned several vehicles with worn, damaged or unbalanced tires and have never experienced a situation where the syptoms of a bad tire were experienced only under braking.    
My question to you would be is it possible or probable in your opinion that a tire is causing the situation in question and if so is there any easy way for me to determine which of the tires is at fault and finally, if it is posssibly a tire what failure in the tires construction might cause it to behave this way. THANX.

Answer
Steve,

This is not tires. It's brakes!  And it looks like you need to find a different place to get your car repaired.

I know of 2 things that cause the symptoms you describe - warped rotors and the rear drums being adjusted too far out.

My daughter's car has the same symptoms and when I adjusted the rear drums, the problem went away.

I do not know of any way to prove that tires aren't the problem without replacing them.  Perhaps moving them to different positions and see what changes, but if nothing changes, I don't think that is proof enough.

Hope this helps.