Maintenance, diagnostics, DPF and emissions, fleet, RV & ag, cost guides and state regulations — written mechanic-to-owner.
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The EGR valve controls how much exhaust gas recirculates back into the intake to cut NOx emissions. Soot buildup, carbon clogging, and heat cycling are the top reasons it fails. Here's how it works, what breaks it, and what repair really costs.
DEF fluid is a urea-water solution that cuts NOx emissions from diesel engines. Learn how DEF works with SCR, why your truck needs it, what happens if you run out, and how to store it right.
Diesel in a gas engine causes rough running, stalling, or a no-start because gas engines rely on spark ignition that diesel can't support. Here's what actually happens, why it differs from gas-in-diesel mistakes, and what fixing it costs.
Yes, you can bolt a supercharger to a diesel — and some classic engines did it from the factory. But here's why almost every modern diesel uses a turbo instead, what changes if you add forced induction, and what it costs to boost a diesel the right way.
Gasoline in a diesel engine is a serious misfuel, not a minor mix-up. It strips lubricity from the fuel system and can wreck the injection pump and injectors in minutes. Here's what actually happens, what it costs to fix, and what to do the moment you realize the mistake.
Learn how to change a diesel fuel filter step by step, including tools, priming the system, OEM service intervals, and the warning signs that mean it's overdue. Includes a cost comparison for DIY versus shop service.
Picking a fleet diesel repair shop is about more than the nearest bay. Learn what certifications, turnaround times, record-keeping, and downtime math actually separate a shop worth keeping from one that'll cost you miles.
A complete DOT annual inspection checklist for fleet managers, built around FMCSA 49 CFR §396.17. Covers required systems, who can sign off, record retention, costs, and how to fold it into your PM program.
CSA scores decide which fleets get pulled for audits, pay more for insurance, and lose freight contracts. Here's how FMCSA's Safety Measurement System calculates your BASIC percentiles — and what the 2026 methodology changes mean for your operation.
