The Part That Costs $40 and Destroys $15,000 Engines: What Fleet Managers Need to Know About Thermostat Failure
A failing thermostat is one of the most misdiagnosed problems in a diesel engine — and by the time most fleet managers figure out what's actually wrong, the engine has already paid a steep price. Understanding how coolant flow problems masquerade as other issues could be the difference between a $40 fix and a catastrophic engine repair. Here's what you need to know.