What to Check
Measure tread depth at all 4 tires in 3 positions across the tread face. Record mm or 32nds. Check spare if equipped. Set tire pressure to the door jamb spec (not the tire wall). Inspect for uneven wear patterns that indicate alignment or inflation issues.
What to Say to the Customer
"Your front tires are at [X]mm, rears at [Y]mm. [Any amount above 4/32":] You've got good tread for now. [At or below 4/32":] I want to flag this — at [X]mm, you're at the threshold where wet-road stopping distance increases significantly. The legal minimum is 2/32", so you're legal, but I wanted you to know where you actually are."
Upsell Trigger
Seasonal: "With the coming [summer heat / winter freeze], tire pressure is one of the most important adjustments you can make. Under-inflated tires flex more and generate more heat — a leading cause of blowouts in July. Cold weather makes pressure drop even further."
Common Missed
Setting tire pressure to the number on the tire sidewall rather than the vehicle specification. The door jamb decal specifies the correct pressure for the vehicle's weight and tire size — sidewall is a maximum, not a target.