: Check for "blow-by" pressure, oil leaks around the block, and even exhaust color. Blue smoke often indicates burning oil.

: The most popular Class 8 truck in North America. It is favored for its Detroit engine efficiency and an unmatched service network.

: Often the most budget-friendly entry point for a quality used Class 8 truck, particularly with the Cummins X15 engine. Essential Pre-Purchase Checklist

: Offers excellent aerodynamics and fuel economy. Like the Peterbilt, it uses reliable PACCAR powertrain components.

A thorough inspection is non-negotiable. Reviewers at BAS World and Signature Truck Center suggest prioritizing these areas:

: Specifically models 760 and 860. These are highly rated for driver comfort, safety tech, and D13 engine longevity, which can exceed 1.2 million miles.

Used Truck Buying Guide: 10 Steps to Take Before Making a Purchase

: Request a download of the engine control module data to see true fuel mileage, idle time, and any recurring fault codes. Used vs. New: The Financial Breakdown