2015 Acura TLX: Bringing the Wheels Back in Balance
August 21, 2015
Awhile back Dan wrote of "a tire imbalance or shudder from the rear" while driving our 2015 Acura TLX. Jay drove it a couple of nights later and echoed his impressions. So the next morning we asked Stokes Tire Service to perform a road-force balance on the rears.
A standard balancing machine starts by spinning a tire-mounted wheel to measure vibration outside of a designated specification. Then it recommends locations to place wheel weights to counteract and minimize that vibration. But it isn't always enough to solve the problem.
Road-force balancing is the next step. No wheel or tire is perfectly round, inherently, so this machine addresses that. Rather than simply spin the tire/wheel, it has a roller to apply pressure that simulates the weight of a car. It measures outer tire dimensions and flags the location of imperfections. Flaws in the wheel circumference are also recorded.
With these results, a tech can dismount the tire, match its high spot with the low spot of the wheel and remount it. This, in addition to standard counter-weights, usually remedies the issue.
In the case of our TLX, road-force balancing seems to have corrected our concern. There is a threshold of 20 pounds on the Hunter machine used by Stokes. Our right-rear tire measured outside of spec at 26 pounds and the left-rear at 24 pounds. After indexing, they measured 15 and 13 pounds, respectively. And the shuddering that Dan and Jay felt is gone.
Mike Schmidt, Vehicle Testing Manager