If the rubber hose on your vehicle's fuel lines is hardened, cracked, leaking or damaged in any other way, it needs to be replaced immediately. Bad fuel lines will result in lost gas mileage along with other problems and hazards. The fuel lines are connected directly to the fuel filter. If the hoses are old and damaged, there's a good chance the filter needs replacing, too, so change it with the fuel line.
Open the fuse box and remove the fuse to the fuel pump. Start the vehicle and let it run until it stops, relieving the pressure from the fuel system, then disconnect the negative battery cable. It also helps to siphon out as much fuel as possible ahead of time.
Remove the fuel filter. This generally means disconnecting the mounting bolts or quick-connect fittings mounting the filter to the fuel tank. Install the new filter onto the tank without connecting the new fuel lines to it.
Disconnect the fuel line from the old filter. (Although you're replacing both, you need the line separate to measure the new line.) Place rags under and at the end of the hose to catch any fuel and loosen the hose's metal clamps to remove it. Disconnect the other end from the steel tube connected to the fuel block.
Clean the end of the steel tube, wiping away any dirt, fuel or pieces of hard rubber. Use the old fuel line hose to cut the length of the new one, making it two inches longer than the old one.
Attach the clamps from the old hose onto the new one while they are loose, making sure they face the same direction as with the old hose. Connect the hose to the steel tube and the new fuel filter.
Check to make sure the new fuel line fits. If the hose has any bends or kinks, remove and trim it until it fits properly. Tighten the clamps onto the hose and then onto the filter and steel tube.
