Truck maintenance is one of the most critical (and most expensive!) responsibilities when managing a fleet. No matter if you have five trucks or five hundred, poor truck maintenance always leads to breakdowns, big downtime, safety risks, and high repair costs.
Strong fleet maintenance, on the other hand, is all about building a structured, repeatable truck maintenance program that protects uptime, controls costs, and extends asset life.
To help you implement a clear maintenance strategy, we designed this guide as a complete, practical fleet maintenance checklist based on U.S. industry standards, covering everything from daily inspections to major service intervals.
1. Pre‑Trip & Daily Inspection (driver responsibility)
Interval: Every shift / every trip
- Engine oil level
- Coolant level
- Power steering fluid
- Windshield washer fluid
- Belts & hoses (visual)
- Tire condition & inflation
- Wheel lug nuts
- Brake air pressure build‑up
- Air leaks (listen)
- Lights, reflectors, turn signals
- Mirrors & windshield
- Wipers
- Horn
- Fifth wheel locking (tractor)
- Trailer connection & airlines
Why it matters: Prevents DOT violations, roadside breakdowns, and safety incidents.
2. Weekly Maintenance Checklist
Interval: Every 7 days or ~2,500 miles
- Check battery terminals & corrosion
- Inspect brake chambers & slack adjusters
- Inspect air lines & electrical lines
- Drain air tanks (if not automatic)
- Check DEF level & DEF quality
- Visual inspection for fluid leaks
- Inspect suspension components
Why it matters: Weekly truck maintenance bridges the gap between daily inspections and PM services. It helps reduce unexpected failures and identify wear patterns early.
3. Preventive Maintenance (PM) Service Levels
PM A – Light Service
Interval: Every 10,000–15,000 miles
- Engine oil & filter change
- Fuel filter (primary)
- Chassis lubrication
- Inspect belts, hoses, and pulleys
- Inspect brake pads/shoes
- Inspect tires & rotation if needed
- Check fault codes
Why it matters: Weekly truck maintenance bridges the gap between daily inspections and PM services. It helps reduce unexpected failures and identify wear patterns early.
PM B – Standard Service
Interval: Every 20,000–30,000 miles
- All PM A items
- Secondary fuel filter
- Air filter inspection/replacement
- Transmission fluid level
- Differential fluid level
- Cooling system pressure test
- Inspect exhaust & DPF mounting
Why it matters: PM B expands fleet maintenance beyond the engine. It emphasizes the drivetrain, cooling, and emission components, which are highly sensitive to neglect.
PM C – Major Service
Interval: Every 50,000–60,000 miles
- All PM A & B items
- Transmission service (fluid & filter, if applicable)
- Differential fluid replacement (if required)
- Full brake inspection & adjustment
- Alignment check
- Steering system inspection
Why it matters: PM C prevents catastrophic failures. This level of truck maintenance addresses high-load components that directly impact safety, handling, and long-term operating costs.
4. Engine System Maintenance
- Engine oil & filter: 10K-30K miles (engine dependent)
- Fuel filters: 15K-30K miles
- Air filter: Inspect every PM, replace as needed
- Valve adjustment: 150K-250K miles
- EGR system inspection: 50K-100K miles
- Cooling system flush: 300K-600K miles or 3-5 years
Why it matters: The engine is the most expensive component in truck maintenance. Proper engine-focused fleet maintenance reduces wear, improves fuel efficiency, prevents overheating, and increases longevity.
5. Aftertreatment System (EPA trucks)
- DPF passive regen: Continuous
- DPF forced regen: As required
- DPF cleaning: 150K-250K miles
- SCR inspection: Every PM
- DEF filter: 200K-300K miles
Why it matters: Aftertreatment failures cause derates, downtime, and massive repair bills. Consistent truck maintenance of DPF and SCR systems keeps fleets compliant and efficient.
6. Brake System Maintenance
- Brake inspection: Every PM
- Brake pads/shoes: 100K-200K miles
- Brake drums/rotors: As worn
- Air dryer cartridge: 100K-150K miles
- Slack adjusters: Inspect every PM
Why it matters: Brakes are absolutely critical for safety and DOT compliance. Strong brake-focused fleet maintenance reduces accident risk and prevents violations.
7. Tires & Wheels
- Tire pressure: Daily
- Tire rotation: 50K-75K miles
- Alignment: 100K miles or irregular wear
- Wheel bearings: Inspect every PM, service at 250K-500K miles
Why it matters: Tires are one of the highest operating costs in truck maintenance. Proper pressure, alignment, and rotation dramatically extend tire life and improve fuel economy across the fleet.
8. Transmission & Drivetrain
- Transmission fluid: 250K-500K miles
- Clutch adjustment: As needed
- Driveshaft & U-joints: Inspect every PM
- Differential fluid: 250K-500K miles
Why it matters: Drivetrain failures create long downtimes and high repair bills. Preventive truck maintenance here protects power delivery and keeps vehicles road-ready.
9. Electrical & Electronics
- Battery test: Every PM
- Alternator output: Every PM
- Starter inspection: 100K+ miles
- Season & wiring inspection: Every PM
Why it matters: Electrical issues are a top cause of no-starts and false fault codes. Strong electrical fleet maintenance improves reliability and reduces diagnostic time.
10. Trailer Maintenance
- Brake inspection: Every PM
- ABS system: Every PM
- Floor & wall inspection: 50K miles
- Door seals & hinges: Every PM
- Landing gear lubrication: Every PM
Why it matters: Trailer neglect leads directly to DOT violations and cargo damage. Good trailer maintenance practices protect the cargo, the trailer itself, and boost fleet reputation.
Each of the 10 core areas of proper truck and trailer maintenance plays an equally important role, and following all of these intervals can significantly increase the longevity of your vehicles.
That said, we all know a checklist alone won’t keep trucks on the road. Turning maintenance into a real, working system takes more than good intentions. It requires organization, clear communication across the team, and a proactive mindset instead of reacting when something breaks.
That’s exactly where FleetMate comes in. The RouteMate’s easy-to-use fleet maintenance platform helps you stay ahead by reminding you about the upcoming services, logging every inspection, and managing repairs through the Work Orders feature, all in one place. This way, it simplifies every single segment of fleet maintenance.
Book a demo with FleetMate today to see how it works and take your maintenance approach to the highest level!
