How often do you change Fuel filter, Oil filter and water/fuel separator?

Oil Change & Fuel Filter @ 25,000mi
Water Separator when it looks like absolute crap which is about every like 10,000.

 

10,000. Not sure if it's bad fuel in the area or because of the additives we have to add or what but the filter turns straight black and starts like scrunching up so we just replace it pretty often, even though filter restriction gauge usually doesn't get that high.

 

I change my oil (t4), oil filter, fuel filter, and water fuel separator about every 12000 miles depending on when I can make it home. I'm probably doing it to often at that milage interval but I want to keep the soot down on my isx15 as much as possible. Really trying to get this truck to 1 million before it needs its first rebuild.

 

250 or 500 hours depending on what the manufacturer recommends.

 

10-15k with an oil change for the filter, fuel the same and one at the 5-7500 mile half way point depending on what work I’m doing

 

Every oil change 12000-15000 miles

 

You didn’t mentioned the engine and year …..