Why do diesel engines seem to outlast gasoline engines? Shouldn’t they be built with the same stress safety factors built in and fail at around the same rate?

Question

Edit: Specifically referring to passenger vehicles and consumer trucks, not commercial vehicles that i assume would be built to go much longer anyway.

In: Technology

Answer 1

Diesel engines operate on simpler engine design than gasoline engines. They also run at lower RPM’s since the fuel has more energy. So the main reasons small diesel engines typically outlast their gasoline counterparts is that they **run at lower RPM’s and do not have spark plugs or complex timing mechanisms**.

However, maintenance is key to a long lasting engine. Most diesel engines have turbo’s, and that can often be the weakest link in a poor maintenance scenario. A turbo replacement can cost thousands of dollars. But if it triggers a runaway engine before you can replace it, then you’ll be replacing the entire engine (A runaway diesel is caused by oil leaking from the turbo into the intake, and causing the engine to run on its own oil. The only way to stop it is to cut off the air intake).