310T Preventive Maintenance and Inspection

Question 1

What is the minimum tread depth required on front (steer axle) tires of a commercial vehicle per FMCSA regulations?

Accepted Answer

4/32 inch

Answer

FMCSA requires a minimum of 4/32 inch tread depth on steer axle tires, which is higher than the 2/32 inch minimum for drive or trailer axle tires.

Question 2

Which fluids should be inspected as standard practice during a preventive maintenance service on a heavy-duty truck?

Accepted Answer

Engine oil, coolant, transmission fluid, power steering fluid, and brake fluid

Answer

A thorough PM service requires checking all fluid levels — engine oil, coolant, transmission, power steering, and brake fluid — to detect early loss or contamination.

Question 3

What is the primary function of an air filter restriction indicator on a diesel engine?

Accepted Answer

To warn when air filter restriction has reached its service limit

Answer

The restriction indicator signals when the pressure drop across the air filter exceeds acceptable limits, indicating the filter must be replaced.

Question 4

Under FMCSA 49 CFR Part 396.17, how often must a commercial motor vehicle undergo a periodic inspection?

Accepted Answer

At least once every 12 months

Answer

FMCSA requires commercial motor vehicles to be inspected at least once every 12 months to verify they meet minimum safety standards.

Question 5

What does a PM-A service interval typically include on a heavy-duty commercial truck?

Accepted Answer

Oil and oil filter change plus a basic visual inspection

Answer

PM-A is the most frequent service interval and covers an oil and filter change along with a general visual inspection of key components.

(310t) Truck and Coach Technician Certification Practice Test

(310t) Truck and Coach Technician Certification Practice Test

310T Preventive Maintenance and Inspection