Truck Cooling System & Radiator Repair
An overheating truck can mean the radiator, water pump, thermostat, or an EGR cooler leaking coolant into places it shouldn’t be. We trace the actual source before replacing parts, since more than one of these can look the same from the driver’s seat.
Symptoms we see
| Symptom | Likely cause | What we do |
|---|---|---|
| Engine temperature climbing on grades or in traffic | Radiator restriction, a failing water pump, or low coolant from an undetected leak | Pressure-test the system and check water pump flow before assuming the radiator is at fault |
| Coolant loss with no visible external puddle | Internal leak — often the EGR cooler crossing coolant into the exhaust | Pressure test to isolate whether the leak is internal or external |
| Temperature swings, slow to warm up or won't reach operating temp | Stuck-open thermostat or a failing temperature sensor | Test the thermostat and sensor readings against spec |
| Visible coolant leak, hose or clamp area | Deteriorated hose, loose clamp, or a cracked fitting | Inspect and replace the affected hose, clamp, or fitting |
| White exhaust smoke with overheating | Coolant entering the combustion chamber — a cracked EGR cooler or head gasket | Pressure test to determine which component is actually failing |
SymptomEngine temperature climbing on grades or in traffic
Likely causeRadiator restriction, a failing water pump, or low coolant from an undetected leak
What we doPressure-test the system and check water pump flow before assuming the radiator is at fault
SymptomCoolant loss with no visible external puddle
Likely causeInternal leak — often the EGR cooler crossing coolant into the exhaust
What we doPressure test to isolate whether the leak is internal or external
SymptomTemperature swings, slow to warm up or won't reach operating temp
Likely causeStuck-open thermostat or a failing temperature sensor
What we doTest the thermostat and sensor readings against spec
SymptomVisible coolant leak, hose or clamp area
Likely causeDeteriorated hose, loose clamp, or a cracked fitting
What we doInspect and replace the affected hose, clamp, or fitting
SymptomWhite exhaust smoke with overheating
Likely causeCoolant entering the combustion chamber — a cracked EGR cooler or head gasket
What we doPressure test to determine which component is actually failing
What the job involves
We pressure-test the cooling system first — it’s the fastest way to tell an external leak from an internal one, and internal leaks (EGR cooler, head gasket) need a very different repair than a bad hose.
Water pump flow and thermostat function get checked against spec, not just visually inspected, since a weak pump can look like a clogged radiator.
If the EGR cooler is the source, that repair is covered in detail on /services/egr-repair — we link you there for the specifics.
Once the actual leak is fixed, we bleed the system properly — an improperly bled cooling system can mimic the original overheating complaint.
What drives the cost
What this costs depends on whether it's an external leak or an internal one, which component is actually failing, and how much of the cooling system has to come apart to reach it. We tell you after we look at it, before we start.
Platforms
- Cummins X15
- EGR cooler cracking on this platform is a common cause of coolant loss that presents as an overheating or white-smoke complaint.
- Volvo D13 / Mack MP8
- DPF/DOC degradation and EGR-related issues on this platform can present alongside cooling system symptoms.
Common questions
How do you know if it’s the radiator or something else?
We pressure-test the whole system first — that isolates whether it’s the radiator, water pump, or an internal leak like the EGR cooler.
Why is my truck losing coolant with no visible leak?
Usually means the leak is internal — the EGR cooler or head gasket letting coolant into the engine or exhaust.
Can I keep driving with an overheating truck?
Not safely for long — you risk head gasket or engine damage. It's worth pulling in before it gets worse.
Is white smoke always the cooling system?
It's one of the most common causes, but we confirm it with a pressure test before assuming.
What does a cooling system repair cost?
Depends on what's actually failing and how much has to come apart to reach it. We diagnose first.
Related services
EGR Valve & Cooler Repair
White smoke at startup and coolant that disappears without a visible leak is the classic sign of a cracked EGR cooler letting coolant cross into the exhaust. We pressure-test the cooling system to confirm it before anything comes apart.
Learn more Engines
Diesel Engine Repair
A diesel engine problem is rarely simple — it's cylinder head, fuel system, turbo, or something deeper, and the fix ranges from a single component to a full overhaul. We diagnose first, then tell you honestly whether it's worth repairing, overhauling, or replacing.
Learn more Engines
Turbocharger Repair & Replacement
A whining turbo, boost that won’t build, or visible smoke from oil in the intake usually means the VGT actuator, a boost leak, or the turbo itself is failing. We isolate the actual source before replacing the turbocharger.
Learn more
Service area
Ready when you are
Call now or send a quote request — we’ll tell you what it takes to fix it.