You are here:

Tires/bent rim or out of round tire?


I recently purchased new tires for my Ford Ranger. The tires that I had replaced were 12 year old Michelin's with 97,000 miles and never had any problems. I replaced them with Cooper Mastercrafts and I'm having a vibration at speeds over 60 mph in the rear end. I returned to the place where I got them and after putting one on the balancer he said that the one tire is 'out of round'.

Back when I first had the Michelins installed, the tire guy at that place told me I had a slightly bent rim but after all of the miles I put on those tires, I could never tell the difference.

My the man at this tire shop misdiagnosing the bent rim as an 'out of round tire' or maybe it's both? Can he tell the difference by just spinning the tire on the balancer?



The people who were in the best position to diagnose this were the ones who had the tire and rim in front of them.  Based on your description, I can't tell which is correct.

Yes, the guy saying the tire is out of round night be overlooking the bent rim.  And, Yes, the guy who said the rim was bent could have been just saying that.

You need to find someone with a Hunter GSP9700 Road Force balancer - and ghe will be able to diagnose which it is.  


All Answers

Answers by Expert:

Ask Experts


Barry Smith


I have over 30 years experience in the design, manufacturing, and testing of tires. I have served as the technical advisor to the "800" number. I have authored or co-authored many publications - usually without credit. I can answer almost any technical question, but please don`t ask me to compare brands. I probably have prejudices because of my work experience.


Member SAE (Society of Automotive Engineers) Member Tire Society (Tire Technical Organization) SCCA Regional Competiton License holder Authored many training manuals on tires, their care and use.

SAE (Society of Automotive Engineers) SCCA (Sports Car Club of America) Tire Society

You may want to visit my web site:

I am a graduate of the University of Dayton, Dayton, OH - BME, 1971 I attended graduate school at the University of Akron - but did not complete my PhD - something I regret.

©2017 All rights reserved.