Match-Mounting Tires & Wheels
The tires and wheels are match-mounted at the assembly plant. This means that the radially stiffest part of the tire (or "high spot") is matched to the smallest radius (or "low spot") of the wheel, which helps to provide the smoothest possible ride. The "high spot" of the tire is originally marked by a paint dot or an adhesive label on the outboard sidewall. This paint dot or label will eventually wash off the tire. The "low spot" of the wheel is at the location of the valve stem.
Before dismounting a tire from its wheel, scribe a line on the tire at the valve stem to assure that it is remounted in the same position. Replacement tires that are of original equipment quality will have their high and low spot marked in the same manner.