The ongoing fight over how often to change fuel filters on older Cummins engines

I keep seeing guys online saying change your fuel filter every 15,000 miles on a 5.9 Cummins, but then the old timers at my shop in Ohio swear by 30,000 miles and say the extra filtering just makes the injection pump rely on new filters too much. My own 2001 Dodge with 280k miles ran fine on a 20k mile schedule for years until I stretched it to 32k and got stalling on a grade. So what's the real sweet spot for ISB engines that see highway and towing, not just light duty?

3 comments

3 Comments

the_laura26d ago

Right, so I stretched mine once too and got a nice stall going up a hill with a trailer behind me, real fun. The old timers saying new filters make the pump "too reliant" just sounds like some engine astrology to me, like saying clean oil makes your bearings too soft. On a 5.9 that's seen some highway miles, 20k is definitely the sweet spot if you're towing, 30k might be okay for strictly light duty but it's a gamble with that old injection pump. If you're getting stalling at 32k that's your engine screaming at you to stop being cheap, so I'd stick with 20k and change the fuel filter with every other oil change to make it easy.

daniel_lane3026d ago

Engine astrology, I'm stealing that one. Next thing you know someone will be telling me changing the air filter makes the turbo breathe too easy.

seth68326d ago

Right there with you, that uphill stall is a nightmare nobody needs.