Preventive Maintenance for Trailers & Trucks: San Antonio Fleet Guide 2026
Preventive maintenance (PM) is the single biggest factor in reducing breakdowns, extending equipment life, and staying DOT-compliant. In San Antonio’s hot, dusty, high-traffic environment, skipping PM can turn a $200 service into a $5,000 emergency.
At Ace Welding & Trailer, we help fleets and owner-operators set up PM schedules that save money and downtime. With 75+ years serving local haulers, we’ve learned exactly what works in Texas conditions.
This guide covers a complete PM schedule for trailers and trucks, common items to check, and how to partner with a San Antonio truck & trailer repair shop to stay ahead of problems.
Why Preventive Maintenance Pays Off in San Antonio
- Texas heat thins fluids, dries seals, and stresses hydraulics
- Road salt & grit corrode frames, brakes, and electrical
- Heavy loads & constant use wear brakes, bearings, and suspension fast
- DOT roadside inspections are frequent – out-of-service = lost revenue
A good PM program can cut repair costs 30–50% and reduce downtime dramatically.
Trailer Preventive Maintenance Schedule
Daily Pre-Trip (5–10 minutes)
- Tires: Pressure, tread, cuts
- Lights & reflectors: All working
- Chains & binders: Secure, no stretch
- Brakes: Air pressure build, no leaks
- Coupler/kingpin: Locked, no play
Weekly (15–30 minutes)
- Grease all zerks (suspension, landing gear, slack adjusters)
- Check brake pushrod stroke
- Inspect wheel bearings for heat/play
- Clean & check lights/reflectors
- Look for frame rust/cracks
Monthly (30–60 minutes)
- Full brake inspection (linings, drums, chambers)
- Check suspension U-bolts torque
- Inspect air bags/shocks
- Test landing gear operation
- Check electrical connections
Quarterly (1–2 hours)
- Repack wheel bearings
- Align axles if uneven wear
- Test air dryer function
- Inspect all hoses/lines
Annually (Shop Visit)
- Certified state inspection
- Thickness test if tank trailer
- Full frame/suspension inspection
Semi-Truck Preventive Maintenance Schedule
Daily Pre-Trip
- Lights, tires, air pressure
- Brakes, coupling
- Fluid levels (oil, coolant)
Weekly
- Grease U-joints, kingpins
- Check slack adjusters
- Inspect shocks
Monthly
- Full brake stroke & lining check
- Torque U-bolts
- Test A/C & electrical
Quarterly
- Oil/filter change
- Air dryer cartridge
- Alignment check
Annually
- DOT inspection
- Transmission/differential service
- Full suspension rebuild if needed
Tools & Supplies Every Fleet Should Have
- Grease gun & high-temp grease
- Torque wrench
- Air pressure gauge
- Flashlight & inspection mirror
- Spare bulbs, fuses, seals
How Ace Welding & Trailer Helps with PM
- Create custom PM schedules
- Perform quarterly/monthly services
- Stock parts for same-day fixes
- Certified inspections & R-Stamp repairs
Stay ahead of breakdowns.