Diesel Repair Blog
Long-form field guides for heavy-duty trucks — written for drivers and shop techs who need practical answers.
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Emissions
DEF Crystal Buildup: Prevention and Repair
Why DEF crystallizes in lines, tanks, and dosing valves — and how shops clear crystals without wrecking the SCR system.
2026-07-20
Emissions
SCR Derate: What Drivers Should Do When Power Is Cut
Practical steps for drivers and dispatch when SCR or DEF faults trigger a derate — from limp mode response to getting the truck fixed right.
2026-07-20
Emissions
How to Clean a DPF Filter on a Heavy-Duty Truck
Learn how to clean a DPF filter on a heavy-duty truck, including soot vs ash diagnosis, on-truck and off-truck cleaning methods, safety steps, costs, and prevention tips for fleet uptime.
2026-07-19