A 12‑ton truck arrived at the shop with a no‑start condition after a long haul.

My task was to quickly identify the root cause and get the truck back on the road.

I first checked the battery voltage and connections, then inspected the starter relay and fuses. Using a diagnostic scanner, I read any fault codes, performed a fuel pressure test, and verified glow plug operation. After ruling out electrical issues, I inspected the fuel pump and injectors for blockage.

The fault code indicated a faulty fuel pump relay, which I replaced. The engine started on the first try, and the driver was back on schedule within two hours.

During a routine inspection on a fleet of 18‑wheelers, I noticed several trucks experiencing reduced braking performance.

Identify the root causes and implement corrective actions to prevent future failures.

I inspected the air compressor, checked for air leaks using a soap‑solution test, measured system pressure, and examined the brake chambers and valve assemblies. I found worn brake shoes, a cracked air line, and a malfunctioning compressor governor.

I replaced the brake shoes, repaired the cracked line, and serviced the compressor governor. After the fixes, all trucks passed the brake performance test and the fleet recorded zero brake‑related incidents for the next six months.

Our company schedules quarterly preventative maintenance for all long‑haul trucks to avoid costly transmission failures.

Conduct a comprehensive transmission check that meets OEM recommendations and ensures driver safety.

I drained the transmission fluid, inspected the fluid color and particle count, checked for leaks, examined the torque converter and clutch plates for wear, and verified proper shift timing using a diagnostic tool. I also inspected the cooler lines for blockages and ensured the transmission filter was clean or replaced it if needed.

The maintenance revealed a slight fluid contamination, which I corrected by flushing and refilling with fresh fluid. No wear issues were found, and the trucks continued to operate without transmission downtime for the next service interval.

A client required a retrofit to meet the latest EPA Tier 4 emission standards on a fleet of 2015 diesel trucks.

Modify the engines to achieve compliance without sacrificing performance.

I performed a thorough inspection of the exhaust after‑treatment system, replaced the diesel particulate filter (DPF) and selective catalytic reduction (SCR) components, and calibrated the engine control module using the manufacturer’s software. I also conducted emissions testing on a chassis dynamometer to verify compliance.

All trucks passed the EPA emissions test on the first attempt, and the client avoided potential fines while maintaining fuel efficiency.

During a busy shift, I noticed that a hydraulic lift was leaking oil onto the floor near the tire rack.

Prevent a slip hazard and ensure the lift could be used safely.

I immediately placed warning signs around the area, reported the leak to the shop manager, and shut down the lift. I then assisted the maintenance team in draining the oil, cleaning the floor with a degreaser, and replacing the faulty seal on the lift cylinder.

The leak was fixed within an hour, the floor was dry and safe, and no injuries occurred. The incident prompted a weekly inspection checklist to catch similar issues early.

A truck arrived with a malfunctioning air suspension that required disassembly of the high‑pressure air lines.

Service the system without risking injury from sudden air release.

I first depressurized the system by opening the service valve and bleeding all air from the lines. I locked out the compressor, used a pressure gauge to verify zero pressure, and wore appropriate PPE. After confirming the system was safe, I removed the faulty air spring, inspected the fittings, and replaced the damaged line. I then re‑pressurized the system gradually, checking for leaks at each step.

The air suspension was restored to full functionality, and the truck passed the post‑repair air system test with no leaks detected.

A driver was upset because his truck kept losing power after a recent repair, and he didn’t understand the technical cause.

Explain the issue in plain language and restore his confidence in the service shop.

I used a simple analogy comparing the fuel pump to a heart that needs a steady beat. I showed him the diagnostic scan results on a tablet, pointed out the clogged fuel filter, and explained how replacing it would restore proper flow. I answered his questions patiently and offered a short test drive to demonstrate the improvement.

The driver left satisfied, thanked me for the clear explanation, and continued to use our shop for future maintenance.

A trucking company needed a critical delivery the next morning, but one of their trucks broke down with a transmission issue during the night shift.

Diagnose and repair the transmission before the driver’s departure at 6 AM.

I coordinated with the night crew to prioritize the job, performed a rapid diagnostic using a handheld scanner, identified a faulty shift solenoid, and ordered the part from the on‑site inventory. While waiting for the part, I pre‑assembled the replacement to save time. Once the solenoid arrived, I completed the swap, performed a quick road test, and documented the work.

The truck was back on the road by 5:30 AM, allowing the driver to meet the delivery schedule without delay.

The industry is rapidly adopting electronic control modules and advanced telematics in heavy‑duty trucks.

Continuously update my knowledge to service modern fleets effectively.

I subscribe to OEM service bulletins, attend quarterly technical webinars hosted by manufacturers, and participate in local trade‑school workshops. I also maintain a reference library of service manuals and use a diagnostic software subscription to practice on simulated fault codes. Whenever a new tool is released, I schedule hands‑on training with the vendor’s representative.

My up‑to‑date expertise has reduced diagnostic time by 20% and earned positive feedback from fleet managers who appreciate my ability to handle the latest technology.