Ford trucks equipped with diesel engines have been around since 1983. The Ford diesel engine costs more than its gasoline counterpart, but the expense is offset by better fuel economy, more power and torque, and better longevity. However, the demands on a diesel engine require rigorous maintenance practices. One of the best things you can do for a diesel engine is to change the fuel filter regularly to keep dirt, water and other contaminants from getting into the fuel injection system.
Open the bonnet and locate the fuel filter. It's toward the front of the engine. Gain access to the filter housing by using a wrench to loosen and remove the two nuts holding the black plastic trim cover in place.
Attach a 2-foot length of 5/16-inch rubber hose over the end of the drain petcock, which is on the lower left side of the fuel filter housing. Place a drain pan on the ground under the truck, and route the other end of the hose into the pan.
Drain the remaining fuel in the fuel filter housing by turning the drain petcock counterclockwise with your fingers. Only a few ounces will drain out; close the drain petcock after the fuel has drained. Remove the rubber hose from the drain petcock, as well as the drain pan from under the truck.
Unscrew with your hand the round plastic cover from the top of the fuel filter housing. If the cover is secured too tightly, use a large set of channel locks to remove it, but be careful not to damage the cover or housing. Discard the O-ring seal. Remove the fuel filter from the housing and dispose of it properly.
Install the larger of the two O-rings that came with the new filter onto the fuel filter housing cover. Then install the smaller O-ring on the filter. Check the old fuel filter for the correct placement of the O-ring if you are not sure where to install it.
Insert the fuel filter into the fuel filter housing. Screw the fuel filter housing cover back on, in a clockwise direction. Don't over-tighten it.
Reinstall the black plastic trim cover using a wrench, being careful not to over-tighten the two holding nuts.
Let the filter housing fill with fuel before starting. Do this by turning the ignition switch to the "On" position and waiting a few seconds.
Start the truck, and make sure there are no leaks.
Record the fuel filter type and manufacturer in your maintenance records. This will help you find the correct replacement filter when it's time to change it again.