What To Look For When Buying A Used Semi Truck May 2026

: Request a detailed history showing regular oil changes (typically every 15,000–30,000 miles for modern diesels), filter replacements, and cooling system flushes.

: Blue smoke can indicate oil burning, while excessive white or black smoke suggests fueling or aftertreatment issues. what to look for when buying a used semi truck

: Check for excessive crankcase pressure, which can indicate internal engine wear. : Request a detailed history showing regular oil

: Check for documented engine overhauls, transmission repairs, or aftertreatment (DPF/SCR) service. If an engine was rebuilt, verify it was done by a certified mechanic. 000 miles for modern diesels)

Before touching a wrench, review the documentation. A truck's history is the best predictor of its future downtime.

The engine is your most expensive component to repair, making its inspection non-negotiable.