Air Valve Replacement
Relay valves, protection valves and other air valves control how the brakes respond. A failed valve can cause leaks or erratic brake behaviour.
- AvailabilityCalls and messages 24/7
- WhereRoadside, yard or jobsite
- CategoryTrailer Repair
- On-site repairWhere feasible and safe
About air valve replacement.
Relay valves, protection valves and other air valves control how the brakes respond. A failed valve can cause leaks or erratic brake behaviour.
A mobile mechanic can look at the unit where it stands, whether that is the roadside, a yard or a jobsite. That can avoid a tow and shorten downtime when the fault is suited to on-site work.
Part of Trailer Repair.
When you might need it.
Any of these is a good reason to call and describe what the unit is doing.
Brakes slow to apply or release
Air escaping from a valve
Pressure that won't hold
Brake lock-up
What the service involves.
Identifying the faulty valve
Replacing the valve and seals
Leak and function testing
Checking related lines
Causes and good habits.
These are possibilities, not a diagnosis. The only way to know is to test the unit.
Possible causes
- Contaminated air supply
- Worn seals and springs
- Freezing in cold weather
Practical tips
- Drain moisture from air tanks
- Use an air dryer in good condition
What to expect.
Valve parts vary by trailer. Details help us confirm availability.
On-site repair depends on the fault, parts, vehicle condition, safety and service feasibility.
(437) 601-8551Before you call
- Exact location, and direction of travel on a highway
- Truck or trailer type, make and year if known
- What happened and what warnings you see
- Whether the unit is somewhere safe
- A number we can call back
From the first call to the fix.
Call or message
Tell us where the unit is.
Describe the fault
Symptoms, lights, noises, leaks.
Agree the plan
Feasibility and dispatch, discussed honestly.
Diagnose and repair
On site where it is possible and safe.
Services that often go together.
Trailer Air Leak Repair
Trailer air leaks drain the brake system and can lock up the spring brakes.
Trailer Brake Repair
Trailer brakes take a lot of abuse.
Brake Chamber Replacement
A failed brake chamber leaks air or fails to apply or release.
Air Compressor Repair
The air compressor feeds the brakes and air accessories.
Frequently asked questions.
Which valves fail most often?
It varies. Diagnosis identifies the actual failed part.
How do I request this service?
Call (437) 601-8551 or message us on WhatsApp with your location and the issue. For non-urgent work, use the contact form.
Can every repair be done on site?
No. It depends on the fault, parts, vehicle condition, safety and feasibility.
Stranded on the Road? Let's Talk.
Tell us where your truck or trailer is located and what happened. Contact Fellows to discuss mobile repair options and next steps.
(437) 601-8551Have ready: exact location, truck or trailer type, what happened or what warnings you see, whether the unit is somewhere safe, and a callback number. Timing, dispatch and on-site repair depend on location, availability, the fault, parts and safety.