Truck Equipment Installation & Repair Flashcards

When welding a bracket onto a heat-treated truck frame, why is welding often discouraged by manufacturers?

Answer: Welding heat can weaken the heat-treated steel and create stress risers

Localized heat alters the frame's metallurgy, creating stress risers that can lead to cracks.

A technician installs a fifth wheel. What adjustment ensures proper kingpin engagement?

Answer: Setting the locking jaw clearance per the manufacturer's spec

Correct jaw-to-kingpin clearance ensures a secure lock without excessive play.

What is the correct grade of bolt typically required for frame-mounted equipment on heavy trucks?

Answer: Grade 8 (high-tensile) bolts

Grade 8 bolts provide the tensile strength needed to handle frame-mounting loads.

When routing hydraulic hoses for a dump body, hoses should be:

Answer: Secured and protected from chafing against sharp edges and moving parts

Securing hoses prevents chafing failures that cause leaks and loss of system pressure.

A service body's compartment doors won't stay closed on rough roads. The most likely fix is:

Answer: Adjusting or replacing the rotary latches and strikers

Worn or misaligned rotary latches fail to hold doors closed under vibration.

Why is it important to verify GVWR and axle weight ratings before adding equipment to a truck?

Answer: Exceeding ratings is unsafe and illegal and can cause component failure

Installed equipment adds weight that must stay within legal and safe rating limits.

What is the function of an air-shift PTO control compared to a cable-shift control?

Answer: It uses vehicle air pressure to engage the PTO instead of a mechanical cable

Air-shift PTOs engage via an air cylinder rather than a manually pulled cable.