Calling all diesel guys!

Yep, the lift pump trucks are up at the fuel filter and have to pull fuel from the tank. Later they shifted to in tank pumps that pushed to the fuel filter.

I pulled apart my lift pumps that failed and they all had the same problem. The vanes that slid out during rotation to pull the fuel would wear and get cocked in the pump hub that spun them. You would first see pressure fluctuations, then eventually they would wear so much that they wouldn’t extend anymore and catch the fuel.