O.K. I do know the difference.

However; if a air filter works better semi used than a new one, why is a fuel filter any different?

Why change fuel filter with lesser milage on it? Would it not filter better, with more milage on it, than less? So why change the fuel filter at 10,000 miles than at say 25,000 miles?

Max Owner

I would say because fuel flow restriction is more noticable and or harmful than air flow restriction.

Josh

I guess I see several reasons.

The fuel filter is much more critical because of the size of the passages the fuel must pass through. Fuel is pressurized with a close tolerance pump and shot through a tiny electric valve and then through a tiny orifice.

The air filter is on the intake side of a exhaust driven turbin then through a large valve into a combustion chamber the back out through a valve and back through the turbin and into the exhaust pipe. Tolarences are not as tight and where the tolarences are tight the chance of getting a piece of dirt into the space is much less.

I hope this helped a little.

Fuel filters will also filter better when used but you don't want to let the pressure drop get too high on the fuel filter as some (small amt.)of contaminates will begin to pull through as the down stream side of the media begins to fluff. (fiber separating). Same thing for the air filter but performance will drop drastically or the filter will fail before reaching that point.

Just curious. When the air filter info popped back up again, some of this was discussed. Got me thinking about the fuel filter. Wondering if the guys who religiously changed their fuel filters, were having injector issues.

Sorry. The highlight of my Sunday was goin' to church. And trying to get into the new site. :confused:

They both work a little better when dirty but at some point when they get so dirty fuel/air flow is impeded, engine performance suffers and eventually the engine dies.

Bill; I do understand that, but was wondering if changing the fuel filter with lesser milage on it could be allowing finer particles through?

Are people changing the filter at the time it just starts to filter the most efficiently?

Max, I think that the filter is relative to what duty the truck preforms. A puller or a Juiced truck may have some issues extending the fuel filter change, while regular 'air haulers' could probably extend their drop by 2x. Also, remeber how the media is used. Vacuum and pressure will vary the way the filter media performs.
Note: the best way to destroy a fuel pump....... run it out of fuel.

Just thinking out.....well typing out loud, so to speak.

If you want to wait until 25,000 miles before you change your fuel filter be my guest.

However all the posts I have ever read over the last 3 years indicate that you are really pushing your luck at 15,000 miles.

I would suggest you carry a spare fuel filter as many other do.

good luck