New Duramax Question
Hey All, I'm considering a new GMC 3500 single rear wheel diesel and have never owned a diesel before. How often do you have to change the fuel filter on a Duramax? Every 5000 miles? 10000 miles? M...
Forum Discussion
Turtle n Peeps wrote:
Unlike oil filters, fuel filters do not have a bypass system in them.
The more they filter the better they filter (smaller and smaller particle size) until they become restrictive at full fuel flow.
This is 100% correct. Also, anyone with a HPFP, particularly a Bosch CP4.2 HPFP on their Duramax or Ford ABSOLUTELY needs to suck all the water and poop and debris out of the bottom of their fuel filter canister, every single fuel filter change... AND, you absolutely, positively MUST PRIME the whole fuel filter, lines, HPFP, accumulator, rails, and injector of any air in the fuel system, BEFORE ATTEMPTING TO RESTART YOUR ENGINE the first time, after a fuel filter change. Air in the fuel system can cause cavitation of the HPFP, damaging the cam and rollers, and starting a catastrophic HPFP failure. Many HPFP's in VW's and Audi's end up failing shortly after a fuel filter service.
Make sure you positively KNOW the procedure for bleeding and priming your whole fuel system when doing a fuel filter change, and BEFORE you start up your motor, first time after a fuel filter change.
