Rolling Resistance
- Tire size/type & balance
- Wheel bearing friction reduction
-
Proper wheel bearing adjustment
- Tire pressure monitoring
A lot of small stuff to consider in re rolling resistance. A search on wheel bearing adjustment shows it may be source of side-to-side temp discrepancies. Too tight is a possibility (improper method; sloppy work).
A product to consider in re wheel/tire balance:
True Balance
.