The fuel filter is real easy to replace on these trucks. First you need to put a drain pan under front axle then turn the fuel filter drain valve lever open to drain the fuel out of the housing. Then you should use compressed air to blow around the top of the filter housing. You can then loosen the cap by using a 11/8" socket. Remove cap and filter, then install new filter in cap by snapping it in with the hole in filter facing out. Install the new o-ring on cap and thread the cap back in the housing. It is supposed to be torque to 25 ft lbs, but you can just snug it on. It doesn't have to be real tight. Then turn drain valve lever closed. Then all you have to do is just bump the key to the start position and leave key on for 25 seconds, then repeat this again. After 25 seconds you can start the truck. Here is a picture of the filter. I hope I have helped and If you have anymore questions feel free. Thanks!
Refer to maintenance schedules in this manual, or the Owner's Manual for recommended fuel filter replacement intervals.
Draining water from fuel filter/water separator housing:
The housing drain valve (9) (FILTER HOUSING) serves two purposes. One is to partially drain the filter housing of excess water. The other is to completely drain the housing for fuel filter, drain valve, heater element or water-in-fuel sensor replacement.
The filter housing should be partially drained whenever the water-in-fuel warning lamp remains illuminated. (Note that lamp will be illuminated for approximately two seconds when ignition key is initially placed in ON position for a bulb check).