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Diesel crankshaft repair covers the crank itself, its main and rod bearings, and the seals at each end. Route 66 Auto Repair in Upland diagnoses crankshaft problems on diesel pickups and vans, from a leaking rear seal to a deep knock from a spun bearing. Our ASE-certified technicians confirm the cause, show you the evidence, and lay out repair versus replacement options. Your written estimate shows every step before any teardown.
What are the signs of diesel crankshaft trouble?
- Deep, rhythmic knock that rises with engine speed
- Low oil pressure alongside the knock
- Metal flakes in the oil filter
- Oil leaking where the engine meets the transmission
- Oil leaking behind the front pulley
- Crank position sensor codes after a harmonic balancer issue
A seal leak and a bearing failure are very different jobs
A rear main seal leak is common on older diesels. It means removing the transmission, but the engine itself stays together. A front seal is usually easier. Both are repairs we quote with a clear scope.
A knock with metal in the oil points to bearings and possibly a damaged crank journal. That becomes a decision between a crank repair, an engine overhaul or a replacement engine. We walk through the cost and time of each honestly, including when the truck may not be worth it.
Our crankshaft diagnosis and repair process
Step 1: Listen and measure
We locate the knock, check oil pressure with a gauge and inspect the filter for metal.
Step 2: Rule out other knocks
Injector knock, loose accessories and flywheel issues are checked so the diagnosis is right.
Step 3: Present options
Seal repair, bearing and crank work, overhaul or replacement are laid out with parts and time.
Step 4: Repair and break in
After approval, the work is done to spec, oil is changed, and the engine is run and road tested.
What's included in crankshaft diagnosis
Included on the work order
- 01Mechanical oil pressure test
- 02Oil filter inspection for metal
- 03Knock location with a stethoscope
- 04Photos of leaks or debris
- 05Written options with need-now and need-later lines
Is it a need-now or need-later repair?
Need now: call
- Knocking with low oil pressure
- Metal in the oil
Need later: book
- A slow rear main seal seep
- Light oil mist at the front seal
How pricing and timing work
Seal work is priced mainly by the labor to reach it. Bearing and crank repairs involve inspection, measuring and possibly outside work on parts; your written estimate shows every step. If the job grows once the engine is open, we stop and ask again. Related gas-engine work is on crankshaft repair.
Aftercare
After a bearing repair, follow the break-in guidance on the invoice and plan the first oil change early. Keep up with diesel engine oil filter replacement. Watch the oil pressure gauge closely.
Frequently asked questions
Can I drive with a knocking diesel?
No. A bearing knock can turn into a thrown rod quickly. Park it and have it towed. We accept tow-ins.
Is a rear main seal leak urgent?
Usually not, unless oil is dripping on the exhaust or the level drops fast. Many owners plan it with a clutch or transmission job.
Is it better to replace the engine?
Sometimes. It depends on mileage, the vehicle's condition and the damage found. We give you the numbers for each path so you can decide.