Red Seal Transport Trailer Technician study plan

Map every component of a trailer air brake system (supply, service, parking/emergency, and ABS circuits) and explain the function of each valve and reservoir in writing.

Trace air flow from the compressor through the tractor protection valve to the trailer relay valve, listing the pressure at which each protection device actuates.

Demonstrate and document a full pre-trip air brake inspection sequence, including leak-down, low-pressure warning, and spring brake application checks, on a training unit or simulator.

Identify the personal protective equipment and lockout/tagout steps required before servicing an air-braked axle, and state the stored-energy hazards involved.

Calculate the correct pushrod stroke limit for a given chamber type and slack adjuster length using the manufacturer's stroke chart.

Diagnose at least five common air brake faults (slow application, dragging brake, rapid loss of pressure, ABS lamp on, spring brake will not release) by writing a step-by-step diagnostic tree for each.

Measure brake drum diameter, lining thickness, and pushrod stroke on a real or simulated axle, and record whether each measurement passes specification.

Describe the correct procedure to cage and uncage a spring brake chamber safely, including the tools used and the torque values involved.

Explain how to inspect and adjust automatic slack adjusters, and state why manual adjustment of an auto slack is a fault, not a repair.

Outline the ABS blink-code retrieval process for two common trailer ABS configurations and interpret two sample codes.

Identify the major suspension types (spring, air ride, torsion, single-point) and list the load path and wear points of each.

Inspect and measure suspension components - bushings, hangers, U-bolts, equalizers, air springs, and shock absorbers - and record which are within or beyond service limits.

Explain axle alignment geometry (thrust angle, toe, camber) and describe how misalignment shows up as tire wear patterns.

Trace a trailer frame from kingpin plate to rear sill, naming the crossmembers, outriggers, and gussets, and describe how each carries load.

Assess structural damage such as cracks, corrosion, and bent members, and state when a repair requires engineering approval versus a standard weld repair.

Remove, inspect, and refit a hub and bearing assembly on a simulated or training axle, following correct torque and preload sequences.

Explain the difference between bearing adjustment by feel and by dial indicator, and state the specification range for a typical trailer wheel bearing.

Identify wheel and rim types (disc, spoke, aluminum, steel) and state the mounting, torque, and re-torque requirements for each.

Read a tire sidewall and decode load range, ply rating, speed rating, and date code, then match dual tires correctly by circumference.

Describe the causes and inspection signs of irregular tire wear (cupping, feathering, flat spotting) and link each to a suspension, alignment, or inflation cause.

Trace the trailer electrical system from the 7-way connector through the junction box to lamps, ABS power, and auxiliary circuits, and label a full wiring diagram.

Diagnose open, short, and high-resistance faults in lighting circuits using a multimeter and voltage-drop testing rather than parts swapping.

Explain the purpose of the auxiliary (blue) circuit and the proper way to test it at the trailer and at the tractor.

Describe the inspection and maintenance of the kingpin, upper coupler plate, and fifth wheel contact surfaces, including wear limits.

Operate and inspect landing gear, including two-speed gearbox function, leg lubrication, and the correct procedure for cranking under load.

Explain the safety chain, breakaway cable, and air line connection requirements for a towing setup, and demonstrate the correct coupling and uncoupling sequence.

Select and correctly use torque wrenches, micrometers, dial indicators, and pressure gauges, and state the calibration check for each.

Set up and use a torque wrench within its rated range, and explain why extension length and adapters affect applied torque.

Describe the maintenance requirements of specialized trailer systems such as lift axles, dump and tank bodies, refrigeration units, and hydraulic tailgates.

Explain the inspection points for cargo securement hardware, curtains, doors, and seals on a van or flatdeck trailer.

Identify hydraulic system components on a tipping trailer and state the safety checks before and during operation.

Build a job hazard analysis for three trailer repair tasks (wheel-end service, welding on a frame, working under a raised trailer) and list controls for each hazard.

Explain the requirements for supporting a trailer during repair, including jack stand placement, chocking, and never working under an air-supported load.

Describe the documentation and record-keeping expected for a repair, including inspection findings, parts used, and sign-off.

Apply a systematic diagnostic method (verify, gather information, test, confirm) to a written case study and justify each step.

Explain the environmental and disposal requirements for used oil, brake fluid, refrigerants, and scrap tires.

Complete a timed 60-question practice set weighted to the exam blueprint and score at least 80 percent overall.

Score at least 75 percent in each of the four highest-weight domains covered this week and record every missed question with its cause.

Re-teach your three weakest topics from memory, without notes, and verify against reference material.

Re-perform the brake leak-down test, the coupling checklist, and one electrical fault diagnosis under time pressure.