Vehicle InspectionQuestion 2 of 120
What is the minimum legal tread depth in a major groove of a front steering-axle tire on a commercial motor vehicle?
a.4/32 of an inch
b.2/32 of an inch
c.6/32 of an inch
d.1/32 of an inch
Explanation
Steer tires must have at least 4/32 inch of tread in every major groove because they carry the steering and a large share of the load. The 2/32 figure is the minimum for all other tires on the vehicle, and 6/32 and 1/32 are not federal minimums for any position.
Law Reference: 49 CFR §393.75Practice all 120 questions free — no signup required.
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