Brake problems are consistently among the most common reasons trucks get placed out of service at roadside inspections — and air system trouble is behind a lot of them.
Air brake systems take a beating in harbor drayage. A port tractor makes hundreds of stops a week in gate queues and yard traffic, which wears shoes and drums and works slack adjusters hard. Constant hook-and-drop wears out gladhand seals — and on a pool chassis, those seals were already somebody else’s deferred maintenance before you got there. Coastal salt air corrodes fittings and valve threads. And a leak the compressor keeps up with while you are moving can leave a truck unable to release its spring brakes after an hour in a queue.
We come to your truck to find the leak, replace the failed component, and make sure the system builds, holds, and releases air the way it should.
What our Air Brake Service covers
- Finding and repairing air leaks at lines, fittings, valves, and tanks
- Gladhand seal and gladhand replacement
- Trailer air lines — red emergency and blue service — and line hangers
- Brake chamber replacement, including spring brake chambers
- Slack adjuster inspection and replacement, plus pushrod stroke checks
- Brake shoe and drum inspection, and replacement where access allows
- S-cam, cam bushing, and brake hardware problems
- Air dryer and purge valve service, including desiccant cartridge replacement
- Governor testing and replacement
- Air compressor diagnosis — slow build-up, oil in the air system, or no air
- Relay valves, quick release valves, tractor protection valves, and foot valve leaks
- Draining air tanks and checking for oil or water contamination
- ABS warning lights and wheel speed sensor faults on tractors and trailers
What can't be done on the roadside
- Air compressor replacement on engines where it requires removing major components — possible on some trucks, a shop job on others
- Brake jobs on wheel ends with seized hardware or damaged hubs that need extensive disassembly
- Drum machining
- Complete brake overhauls on several axles at once, which are more efficient in a shop
Don’t cage a spring brake to move a truck unless you’re trained to do it and certain you still have enough braking. Caging disables that brake.
Fix it on site or tow it?
Most air brake problems get fixed on site: leaking lines and fittings, gladhands, chambers, slack adjusters, air dryers, and valves are all standard mobile work. A truck that can’t release its brakes because of a leak can often be repaired and driven away the same visit.
A tow is the better option when a wheel end is badly damaged, when the compressor has failed on an engine where replacing it roadside isn’t practical, or when a brake failure caused other damage. A truck should never be driven with a known air system failure that affects braking.
What to tell dispatch when you call
The more dispatch knows up front, the better the odds the mechanic shows up with the right parts and tools on the first trip.
- Whether the low-air warning is on, and what pressure the gauges show
- Whether the brakes won’t release, won’t apply, or are dragging
- Where you hear the leak — tractor or trailer, front or back — and whether it leaks with the brakes applied or released
- Whether the problem started right after hooking a trailer
- If the truck was put out of service, the violations listed on the inspection report
Truck makes & engines we work on
- Freightliner
- Peterbilt
- Kenworth
- Volvo
- Mack
- International
- Western Star
Class 6 through Class 8 trucks, including engines from Cummins, Detroit Diesel, PACCAR, Volvo, Mack, Navistar, and Caterpillar.
Air Brake Service around the harbor & the South Bay
Air brake calls are common in the container yards along Harry Bridges Boulevard and Anaheim Street, where constant hook-and-drop wears out gladhands and lines, and in the terminal gate queues on Terminal Island and at the Long Beach piers. Brake problems also surface at roadside inspections, which are a routine part of moving freight on the 710 and the 110.
Freeways
Service areas
Air Brake Service FAQ
How do I find where my air leak is?
Listen with the engine off. A leak with the brakes released points to the supply side — lines, tanks, and valves. A leak only when the brakes are applied points to service chambers, the foot valve, or relay valves. Our air leak guide walks through it step by step.
Why won’t my trailer brakes release?
Common causes are low air pressure from a leak, damaged or crossed gladhand connections, a failed spring brake chamber, or a problem with the trailer’s relay emergency valve.
What does “brake out of adjustment” mean?
Each brake chamber size has a maximum allowed pushrod stroke. When stroke goes past that limit, the brake loses effectiveness. Automatic slack adjusters are supposed to prevent it, so a brake out of adjustment usually means a slack adjuster or foundation brake part needs attention.
Can’t I just adjust my automatic slack adjusters by hand?
Routinely adjusting automatic slack adjusters by hand hides the real problem. If an automatic slack keeps going out of adjustment, the brake should be inspected to find out why.
Is oil in my air tanks a problem?
Some moisture is normal, but oil suggests the compressor is passing oil or the air dryer isn’t doing its job. Oil in the system damages valves and seals over time.
Can you repair brakes so an out-of-service truck can move again?
Brake-related out-of-service defects can often be repaired right where the truck is stopped. Keep the inspection report handy and ask for an itemized repair record.