Low Oil Pressure
A bad sender, thin or low oil, a clogged filter, a weak pump or worn bearings. Shut it down and call.
Checked:SenderOil pumpBearings
Repair or rebuild
Heavy-duty diesel engines · Louisville, KYEngine Repair, Rebuild& Conversion.
Superior Truck & Trailer repairs, rebuilds and converts heavy-duty diesel engines for semi trucks, fleets and owner-operators in Louisville, KY. From low oil pressure and misfires to a full teardown or a newer engine, it starts with finding what's actually wrong.
- RepairTune-ups to major repairs
- RebuildTorn down, rebuilt to spec
- ConversionA newer or different engine
Three kinds of engine work
Repair, Rebuild Or Convert.
Same diesel, three very different jobs. Pick one and watch what happens to the engine.
Diesel Engine Repair
Everything from basic maintenance and tune-ups to major repairs and overhauls, with the diagnosis first so the fix is the actual problem.
Diesel Engine Rebuild
When an engine is beyond repair, or has high miles or a long time in service, a rebuild takes it all the way down and back up to factory specifications.
Diesel Engine Conversion
For more power and performance, the engine gets replaced with a more powerful and efficient one.
- Upgrade to a newer model engine
- Switch to a different type of diesel engine
- More power and performance
- Can improve fuel efficiency and reduce emissions
Diesel engine repair checklist
Low oil pressure: what gets checked
- Oil pressure sender and gauge reading
- Oil level, grade and condition
- Oil filter and filter bypass valve
- Oil pump, pickup tube and relief valve
- Oil cooler condition
- Main and rod bearing clearance
Engine misfires: what gets checked
- ECM fault codes and live data
- Injector cut-out and balance tests
- Injector cups, seals and O-rings
- Fuel pressure and fuel filters
- Valve lash and overhead adjustment
- Compression and cylinder leak-down
Cylinder head issues: what gets checked
- Head gasket and coolant leaks
- Cracks between valve seats
- Warped head or block deck
- Valves, seats, guides and springs
- Injector sleeves and cups
- Cooling system pressure test
In a typical diesel engine rebuild
Taken apart and inspected
- Cylinder block and deck surface
- Cylinder liners and bores
- Crankshaft and journals
- Camshaft, lifters and followers
- Cylinder head and valve train
- Connecting rods
Commonly replaced
- Pistons and piston rings
- Cylinder liners
- Main and rod bearings
- Gaskets and seals
- Valves, seats and guides as needed
- Oil pump and water pump as needed
Checked on reassembly
- Torqued to factory specifications
- Bearing and ring clearances
- Valve and injector adjustment
- Pre-lube before the first start
- Leak and pressure checks
- Run-in before it goes back to work
Planning a diesel engine conversion
Lined up before the swap
- Engine mounts and crossmembers
- Transmission and bellhousing fit
- Cooling system capacity
- Wiring harness and ECM
- Exhaust and aftertreatment
- Emissions rules for the truck
What a conversion can bring
- More horsepower and torque
- A newer model engine
- A different type of diesel engine
- Better fuel efficiency
- Lower emissions
- Performance matched to the job
When it makes sense
- The engine is beyond repair
- A rebuild costs close to a replacement
- The chassis still has life left
- The work needs more power
- Fuel costs are climbing
- The truck is moving to new work
Diesel engine work, system by system
Cylinder HeadHead gaskets, cracked heads, valves, seats and guides.
Fuel InjectorsMisfires, injector cups and seals, fuel pressure and filters.
LubricationLow oil pressure, oil pumps, oil coolers and leaks.
TurbochargerLow boost, oil in the intake, whining and smoke.
Related repairs
Diagnostics & Electrical RepairFault codes, sensors, wiring and ECM troubleshooting.EGR & DPFEGR valves and coolers, DPF cleaning and regen problems.Coolant System RepairRadiators, water pumps, hoses, thermostats and leaks.Oil & FluidOil changes, filters and fluid service on schedule.Exhaust System RepairManifolds, leaks, pipes and exhaust components.Performance ECM TuningEngine calibration for power and fuel economy.
What drivers notice first
Signs It Needs Engine Work.
Where each one usually leads. Only a diagnosis confirms the cause, so call before it gets worse.
Misfire Or Rough Running
A cylinder dropping out: often an injector or a valve, sometimes low compression.
Checked:InjectorsValve lashCompression
Often a repair
A Knock That Follows RPM
A deep knock that speeds up with the engine can mean rod or main bearings. Don't keep running it.
Checked:Rod bearingsMain bearingsPistons
Can mean a rebuild
Coolant Loss Or Milky Oil
Coolant disappearing or oil turning milky points to the head gasket, the head or the oil cooler.
Checked:Head gasketOil coolerCylinder head
Repair or rebuild
Heavy Blow-By And Oil Use
Pressure pushing out the breather and oil going faster than it should are classic worn ring and liner signs.
Checked:RingsLinersTurbo seals
Can mean a rebuild
Losing Power
Low power can come from fuel, air, boost or compression. The diagnosis sorts out which.
Checked:Fuel systemBoostCompression
Often a repair
Diesel engine rebuild
Inside A Rebuild.
A good option for high-mileage engines or ones that have been in service a long time. A rebuilt engine runs like new.
How engine work moves through the shop
From the first call to a running engine.
Tell us what the engine is doing. We diagnose it, lay out repair, rebuild or conversion, do the approved work and get the truck back into service.
01You call
Tell us the truck, the engine and what it's doing: the noise, the smoke, the light on the dash.
02We diagnose it
The engine gets tested so the work starts from what's actually wrong.
03You pick the path
Repair, rebuild or conversion, laid out up front. Nothing gets done until you approve it.
04You roll
The work gets done, the engine gets 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.
Engine work backed by a full truck shop
The Rest Of The Truck,Same Shop.
Engine work often turns up other jobs. Everything else the truck needs is handled from the same Louisville shop.
Engine repair FAQ · Louisville, KY
Diesel Engine Questions.
Low oil pressure, misfires, head gaskets, rebuilds and conversions: the diesel engine questions truck owners ask most.
(502) 789-6644What's the difference between engine repair and an engine rebuild?
A repair fixes the part or system that failed, from a tune-up to a major repair like a cylinder head. A rebuild is for an engine that's beyond repair: it's completely disassembled, inspected, the worn parts are replaced, and it's reassembled to factory specifications.
When does a diesel engine need a rebuild?
A rebuild makes sense when an engine is beyond repair, or when it has high mileage or has been in service for a long time. Signs like heavy blow-by, rising oil use and low compression can point that way, but a diagnosis confirms it before any teardown. See Diagnostics & Electrical Repair.
What does an engine conversion involve?
An engine conversion replaces the engine with a more powerful and efficient one. That can mean upgrading to a newer model engine or switching to a different type of diesel engine, and it can also improve fuel efficiency and reduce emissions.
What causes low oil pressure in a diesel engine?
A failing oil pressure sender, low or thin oil, a clogged filter, a worn oil pump or pickup, a stuck relief valve, or worn main and rod bearings. A sender or oil problem is a quick repair. Worn bearings can mean a rebuild. Shut the engine down and call when the gauge drops.
What causes a diesel engine to misfire?
Most often a failing injector, a leaking injector cup or seal, low fuel pressure, clogged fuel filters, valve lash out of adjustment, or low compression in one cylinder. Injector cut-out tests and a compression check narrow it down to the cylinder and the cause.
What are the signs of a blown head gasket on a diesel?
Coolant loss with no visible leak, milky oil, white smoke with a sweet smell, bubbles in the coolant, overheating and pressure in the cooling system. A pressure test confirms whether it is the head gasket, a cracked head or the oil cooler.
Can low oil pressure or a misfire be fixed without a rebuild?
Often, yes. Low oil pressure can come from a sensor, the oil, the filter or the pump as well as worn bearings, and a misfire can come from a single injector or valve. The diagnosis decides whether it's a repair or a rebuild.
Do you work on heavy-duty truck diesel engines?
Yes. Superior Truck & Trailer specializes in engine repair, rebuild and conversion for heavy-duty trucks, with the focus on diesel engines. See General Diesel Repair.
Where can I get diesel engine repair near Louisville, KY?
Superior Truck & Trailer does diesel engine repair, rebuilds and conversions 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, the engine and what it's doing.
Is it better to rebuild or replace a diesel engine?
It depends on the engine, the truck and the cost. A rebuild keeps the engine and replaces the worn parts. A conversion puts in a newer or different engine, which can make sense when the engine is beyond repair or the work needs more power.
What is included in a diesel engine rebuild?
The engine is completely disassembled and inspected, worn parts like pistons, rings, liners, bearings, gaskets and seals are replaced, and it is reassembled to factory specifications, with clearances, torque and valve adjustment checked along the way.
How do I know if my diesel engine needs a rebuild?
Heavy blow-by from the breather, rising oil consumption, low compression, a knock that follows RPM and oil in the coolant can all point that way, especially on a high-mileage engine. A diagnosis confirms it before any teardown.
Engine acting up?
Get The Engine Looked At.
Call Superior Truck & Trailer in Louisville, KY with the truck, the engine and what it's doing. We'll get it diagnosed and lay out repair, rebuild or conversion.
(502) 789-6644
3816 Bishop Lane #1, Louisville, KY 40218