Farther Pedal Travel
More pedal before the brakes bite usually means slack adjusters out of adjustment or worn brake pads.
Checked:Slack adjustersPushrod strokePads
Often a repair
Medium & heavy-duty air brakes · Louisville, KY
Heavy-DutyBrake Repair.
Drum brake assemblies, worn brake pads, slack adjusters and leaks in the compressed air system. Superior Truck & Trailer repairs and maintains brakes on medium and heavy-duty trucks, fleets and trailers in Louisville, KY.
- Drum BrakesPads, drums and S-cams
- Slack AdjustersCalibrated to stop straight
- Air SystemLeaks, lines and chambers
Where stopping power gets lost
Drums, Slacks Or Air.
Pick one and watch the brake apply: the drum, the slack adjuster that sets it, and the air that works it.
Common Drum Brake Services
Drum brake assemblies bring trucks as heavy as 100,000 pounds to a stop. Brake pads last a while, but they wear, and you won't always notice.
Slack Adjuster Calibration
Slack adjusters take up the slack as the pads wear. They're automatic, but they can and often do malfunction, and one small error can be catastrophic.
Compressed Air System
A leak somewhere in the compressed air system takes stopping power with it. Pick where it starts.
Drum brake checklist
Brake pads: what gets checked
- Lining thickness at the thinnest point
- Cracks, glazing and missing pieces
- Oil or grease on the linings
- Pads matched side to side on the axle
- Shoe rollers and anchor pins
- Return springs
Brake drums: what gets checked
- Heat cracks across the braking face
- Scoring and hard spots
- Drum diameter against the stamped limit
- Bell-mouthing and out-of-round
- Balance weights
- Hub and wheel bearing condition
S-cams: what gets checked
- S-cam head wear
- Camshaft bushings and seals
- Camshaft play
- Shoe rollers and retainers
- Return springs
- Spider and anchor pins
Slack adjuster checklist
Poor braking: what gets checked
- Pushrod stroke at each wheel
- Slack adjuster function
- Brake pad and drum wear
- Chamber sizes matched per axle
- Air pressure at the chamber
- Brake timing and balance
Pulling: what gets checked
- Stroke compared side to side
- Mismatched pads or drums
- Seized S-cam or bushings
- Grease on a lining
- Chamber and pushrod on each side
- Alignment and tire pressure
Pedal travel: what gets checked
- Stroke on every brake
- Self-adjusting mechanism
- Clevis and pin wear
- Worn linings taking up travel
- Air leaks during an application
- Brake valve and pedal linkage
Air brake system checklist
Air lines: what gets checked
- Audible leaks, applied and released
- Chafed or kinked lines
- Fittings and gladhands
- Line routing and supports
- Leak-down rate on the gauges
- Trailer supply and service lines
Brake chambers: what gets checked
- Service diaphragm leaks
- Spring brake operation
- Chamber housing and clamp
- Pushrod alignment
- Dust plugs and caging bolts
- Mounting studs and brackets
Tanks and valves: what gets checked
- Water and oil in the tanks
- Drain valves
- Air dryer cartridge
- Compressor build-up time
- Governor cut-in and cut-out
- Low air warning
Brake work, part by part
Brake Pads & ShoesPad life measured, linings replaced, shoes and rollers checked.
Brake DrumsHeat cracks, scoring and wear beyond the limit.
S-Cams & BushingsWorn cams, loose bushings and tired return springs.
Slack AdjustersCalibration, stroke checks and replacement.
Brake ChambersService diaphragms, spring brakes and pushrods.
Air Lines & ValvesLeaks, fittings, tanks, drains and the air dryer.
Related repairs and services
Tire RepairTires that wear from brakes that drag or pull.Axle RepairHubs, bearings and seals at the same wheel end.Suspension RepairSprings and mounts that change how the truck stops.Diagnostics & Electrical RepairABS lights, sensors and wiring.DOT InspectionsBrake adjustment and air system checks on the annual.Preventative MaintenancePad life and slack checks on a schedule.
What drivers notice first
Signs The Brakes Need Work.
Where each one usually leads. Brake problems don't get cheaper or safer with time.
Pulling To One Side
A truck that pulls when it brakes has one side doing more of the work: adjustment, a lining or a stuck S-cam.
Checked:Slack adjustersLiningsS-cams
Often a repair
Air Pressure Dropping
A gauge that falls with the truck parked, or a hiss you can hear, means a leak in a line, fitting, valve or chamber.
Checked:LinesFittingsChambers
Often a repair
Low Air Warning
Pull over safely. The spring brakes can come on as pressure keeps dropping. Call before you drive it.
Checked:CompressorGovernorLeaks
Stop and call
Grinding Or Squealing
Metal-on-metal grinding means a lining is gone and the shoe is cutting the drum. Brakes don't fix themselves.
Checked:PadsDrumsShoes
Repair now
A Hot Or Smoking Wheel
A wheel end much hotter than the others means a brake dragging: a stuck S-cam, a weak spring brake or bad adjustment.
Checked:S-camChamberAdjustment
Repair or replace
Brake work
At The Wheel End.
Every brake job starts at the wheel end, and the air system that feeds it gets checked too.
How brake work moves through the shop
From the first call to a straight, sure stop.
Tell us how it stops, pulls or leaks. We check the brakes, lay out the repair, do the approved work and get the truck back into service.
01You call
Tell us the truck and what the brakes are doing: the pull, the pedal, the hiss.
02We check the brakes
Pads measured, slack adjuster stroke checked, and the air system leak-tested applied and released.
03You approve the repair
The repair and the parts, laid out before any work starts. Nothing gets done until you approve it.
04You roll
The work gets done, the brakes get checked, and the truck goes back to work.
Working trucks, real shop work
The work happens here, on the road and in the bay.
The trucks, trailers, service vehicles, roadside calls and shop work behind the services on this site. This is the kind of commercial equipment Superior works on every day in and around Louisville.
Truck repair customer reviews
What Drivers SayAbout The Shop.
Read customer feedback on Superior Truck & Trailer's repair work, communication, and service experience in Louisville.
Brake work backed by a full truck shop
The Rest Of The Truck,Same Shop.
Brake work often turns up other jobs. Everything else the truck needs is handled from the same Louisville shop.
Brake repair FAQ · Louisville, KY
Truck Brake Questions.
Brake pads, slack adjusters, air leaks and pulling: the brake questions truck owners ask most.
(502) 789-6644How often do truck brake pads need to be changed?
Brake pads last for quite a while, but they need to be changed every so often, and how often depends on miles, loads and the kind of driving. You won't always notice symptoms as they wear, so the pads should be measured. Superior Truck & Trailer has the tools to measure brake pad life.
Why can't I tell my brake pads are worn?
The slack adjuster takes up the slack a worn pad creates, which keeps the brakes working but hides the wear. The truck can feel normal while the pads get thin, which is why pad life gets measured instead of guessed.
What are the symptoms of a bad slack adjuster?
Poor braking performance, pulling to one side when braking, and farther brake pedal travel. Slack adjusters are designed to work automatically, but they can and often do malfunction.
Why do slack adjusters need to be calibrated?
Slack adjusters are an integral part of the drum brake assembly, and one small error can have catastrophic consequences. Getting them calibrated by a trained technician keeps every brake doing its share of the work.
What causes an air brake leak?
Cracked, chafed or loose air lines and fittings, a leaking brake chamber diaphragm, worn gladhand seals, or a valve, drain or air dryer that won't seal. A leak can show up only with the brakes applied or only with them released.
How do I check a truck for an air leak?
With the air system at full pressure and the engine off, listen around the lines, chambers and valves, and watch the gauges with the brakes released and then applied. A pressure drop faster than your air brake check allows means find the leak before you drive.
Why does my truck pull to one side when braking?
One side is braking harder than the other. The usual causes are slack adjusters out of adjustment side to side, mismatched or contaminated linings, a sticking S-cam, or a chamber problem on one wheel. Alignment and tire pressure can add to it.
What does the low air warning mean?
The low air warning comes on when pressure in a reservoir drops below a safe level. Pull over safely and don't keep driving, because the spring brakes can apply as pressure keeps dropping. Call and have the compressor, governor and leaks checked.
What causes brake drums to crack?
Heat. Drums crack from repeated hard stops, heavy loads, a dragging brake, or brakes out of adjustment that leave other drums doing extra work. Heat cracks that run across the braking face mean the drum gets replaced.
Do you repair brakes on medium-duty trucks too?
Yes. Superior Truck & Trailer offers brake repair and maintenance for medium and heavy-duty trucks, from drum brake assemblies to leaks in the compressed air system.
Are out-of-adjustment brakes a DOT problem?
Yes. Brake adjustment is checked at roadside inspections and on the annual DOT inspection, and brakes out of adjustment are one of the most common violations found. Keeping slack adjusters calibrated keeps the truck in service.
Where can I get truck brake repair near Louisville, KY?
Superior Truck & Trailer repairs medium and heavy-duty truck brakes at 3816 Bishop Lane in Louisville, KY, for trucks from Louisville and the surrounding Kentucky and Southern Indiana counties. Call (502) 789-6644 with the truck and what the brakes are doing.
Brakes pulling, fading or leaking?
Get The Brakes Checked.
Call Superior Truck & Trailer in Louisville, KY with the truck and what the brakes are doing. We'll check them and lay out the repair.
(502) 789-6644
3816 Bishop Lane #1, Louisville, KY 40218