The GMC Sonoma is GMC's light-duty truck. This truck uses an in-line fuel filter to pull the debris and sediment out of the fuel as it is pushed to the engine from the fuel tank. Replacing this filter will help to improve fuel economy and also increase engine performance. The recommended interval for replacement is 30,000 miles. The filter should also be replaced when changing out the fuel pump.
Park the truck on a flat and level surface. Ensure the wheels are chocked and the parking brake is set.
Open the hood for access to the fuse panel behind the battery. Open the fuse panel and pull the fuel pump relay. The relays will be labeled for easy identification.
Start the truck. Allow the truck to idle until it stalls. This will depressurize the fuel system. Insert the relay back into the fuse panel.
Find the filter under the truck. The filter is located by the driver side underneath the truck. Following the fuel line coming out of the fuel tank will also help you to find the filter.
Loosen the outlet line from the filter by holding the stationary nut on the filter with a line wrench. Loosen the nut on the fuel line with a second wrench.
Pull the inlet line off by separating the tabs on the quick disconnect fitting. Pull it away from the filter.
Unbolt the mounting bracket with a socket wrench. Pull the bracket and the filter off the frame rail.
Slide the new filter on the bracket. Tighten it to the frame rail with the socket wrench.
Push the inlet line onto the filter. The fitting will lock in place once it is pushed far enough on the inlet pipe.
Bolt the outlet line onto the filter with a line wrench. Hold the inner stationary nut with a line wrench and tighten the line down with a second wrench.
Start the truck. Observe the filter for any leaks.
