Gmc Fuel Filter: Changing And Maintenance Guide

Changing the fuel filter in your GMC Envoy is a relatively straightforward process, but it's important to take the necessary precautions and follow the correct steps to ensure a safe and successful outcome. Here's a step-by-step guide to help you through the process:

Step 1: Locate the Fuel Filter

The fuel filter in your GMC Envoy is located on the driver's side, underneath the car, near the fuel tank.

Step 2: Prepare the Vehicle

Park your car on a level surface and engage the parking brake. Make sure the engine is cool before starting work.

Step 3: Relieve Fuel System Pressure

Locate the fuse box and remove the fuse for the fuel pump. Start the engine and let it run for a minute before shutting it off. Reinstall the fuse.

Step 4: Disconnect the Battery

Disconnect the negative terminal of the battery to prevent accidental starting during the procedure.

Step 5: Jack Up the Vehicle

If the fuel filter is located underneath the car, use a jack to raise the vehicle and securely support it on jack stands.

Step 6: Place a Container Under the Fuel Filter

Place a suitable container, such as a bowl or bucket, under the fuel filter to catch any fuel that may spill during the process.

Step 7: Remove the Fuel Lines and Clips

Use a flat-head screwdriver to remove the plastic clips holding the fuel filter in place. Then, carefully slide the fuel lines away from the filter and remove them from the nozzles on both ends of the filter.

Step 8: Remove the Old Fuel Filter

With the clips and fuel lines removed, slide the old fuel filter out of its bracket. Be careful not to spill any remaining fuel.

Step 9: Compare the New and Old Fuel Filters

Before installing the new fuel filter, compare it to the old one to ensure they have the same dimensions and nozzle sizes.

Step 10: Install the New Fuel Filter

Slide the new fuel filter into the bracket, ensuring it is seated properly. Reattach the fuel lines and secure them with the plastic clips.

Step 11: Lower the Vehicle and Reconnect the Battery

Once the new fuel filter is securely in place, lower the vehicle from the jack stands and reconnect the battery.

Step 12: Final Checks

Start the engine and check for any leaks. If there are no leaks, your new fuel filter is successfully installed!

GMC Envoy fuel filter location

The GMC Envoy fuel filter is located on the driver's side of the car, underneath the vehicle, near the fuel tank. The location of the fuel filter can vary from one car to another, but the procedure for replacing it remains the same. If you are unable to locate the fuel filter, follow the fuel pipes.

Step 1: Release Fuel Filter Pressure

Locate the fuel pump relay under the fuse box housing according to the fuse map. Start the engine and then remove the fuse. The car will run out of fuel. Stop the engine and reinsert the fuse.

Step 2: Remove the Fuel Filter

Take out the cap of the pipe attached to the fuel filter to release the remaining pressure from the pipe. To do this, push in with a screwdriver on the pipe tab. Prepare a receptacle to collect any leakage. Remove the first and second pipes. Use a screwdriver to release the clamp that holds the fuel filter attached to the vehicle's body.

Step 3: Install the New Fuel Filter

Take out the old fuel filter and insert the new one. Tighten the clamp. Remove the caps on the new fuel filter and insert the hoses back onto the fuel filter. Tighten the caps.

Step 4: Final Checks

Check for any leakages and then start the engine.

It is recommended that you replace the fuel filter according to your owner's manual and that this operation is done at a car service.

GMC fuel filter replacement procedure

Disclaimer: *This is a general step-by-step guide for GMC fuel filter replacement. The specific process may vary slightly depending on the model and year of your GMC vehicle. Always refer to the owner's manual or seek advice from a qualified mechanic if you are unsure about any steps or procedures.*

Tools Required:

• Trim fastener removal tool or a flathead screwdriver
• 10mm socket and socket wrench
• Medium-size channel lock style pliers
• Two wrenches (for screw-in fittings)
• Deep socket or wrench
• Pick tool or small flathead screwdriver
• Small angled pliers
• 12mm bolts

Step-by-Step Guide:

Step 1: Relieve Fuel System Pressure

Before starting any work on the fuel system, it is crucial to relieve the fuel system pressure. Refer to Chapter 4 of your GMC repair manual for detailed instructions on how to safely release the pressure.

Step 2: Raise and Secure the Vehicle

Use a jack to raise the vehicle and securely support it on jack stands. This will provide better access to the fuel filter, which is typically located near the fuel tank.

Step 3: Locate the Fuel Filter

For GMC Envoy models from 2003 to 2008, the fuel filter is located on the driver's side, under the car, near the fuel tank. For GMC Sierra HD models from 2001 to 2016, the fuel filter is on the passenger side of the Duramax engine, below the air intake tube.

Step 4: Clean the Fuel Inlet and Outlet Line Fittings

Use compressed air or carburetor cleaner to clean any dirt or debris around the fuel inlet and outlet line fittings of the fuel filter. This will help ensure that no contaminants enter the fuel system during the replacement process.

Step 5: Remove the Fuel Filter

• Have spare rags or a small container ready to catch any spilled fuel from the filter assembly.
• Use a flare-nut wrench to disconnect the fittings. Remove the nuts on the carriage bolts to detach the fuel filter and its bracket.
• Use an open-end wrench to steady the hex on the filter, and then separate the fuel line from the filter using a flare-nut wrench to avoid rounding off the corners of the fuel line nuts.
• Detach the fuel filter mounting bracket nuts and carefully remove the old fuel filter.

Step 6: Prepare the New Fuel Filter

• Check that the old gasket or O-ring is not stuck to the fuel filter head, and remove it if necessary.
• Inspect the water-in-fuel sensor assembly for any damage. If it is damaged or worn, replace it with a new one.
• Lubricate the new O-ring and gasket (if provided with the new fuel filter) with clean engine oil before installing them.

Step 7: Install the New Fuel Filter

• Install the new fuel filter by following the removal steps in reverse. Ensure that the water-in-fuel sensor wire does not get tangled during the process.
• Do not tighten the new fuel filter with tools; install it by hand only.
• Open the bleed valve on the fuel filter head.
• Prime the new fuel filter by pumping the plunger on the fuel filter housing until all air escapes and fuel starts to flow out of the bleed valve. Then, close the bleed valve, being careful not to over-tighten it.

Step 8: Reinstall Components and Check for Leaks

• Reinstall the inner fender and intake tube that were removed earlier.
• Start the engine and slide underneath the vehicle to check for any fuel leaks.
• The engine may run rough for the first 30 seconds after starting. If it does not smooth out after about a minute, re-bleed the system and repeat the pumping process.

Additional Notes:

• For GMC Sierra HD models, it is recommended to replace the entire fuel filter housing as a unit, rather than just the fuel filter. This can make the process easier and reduce the risk of leaks.
• Always exercise extreme caution when working on the fuel system. Gasoline is highly flammable, so ensure there are no open flames or sparks nearby. Wear safety gear, such as latex gloves and safety glasses, and have a fire extinguisher on hand.
• Refer to your owner's manual for the recommended fuel filter replacement interval for your specific GMC model.

GMC fuel filter replacement safety precautions

Before you start

Before attempting to replace the fuel filter on your GMC, there are a few safety precautions you should take to ensure the process goes smoothly and safely.

Firstly, make sure you have the necessary tools for the job. You will need a socket wrench, some spare rags or a small container, and safety gear such as gloves and safety glasses. It is also recommended to work in a well-ventilated area to minimise the risk of inhaling fuel vapours.

Disconnect the battery

As a safety precaution, always disconnect the battery before working on your vehicle. Disconnect the negative terminal (black) and wrap it in a towel to prevent it from touching anything metal and creating a spark.

Relieve the fuel system pressure

The fuel system is under constant pressure, so it is important to relieve this pressure before disconnecting any fuel lines. Refer to Chapter 4 of your GMC manual for step-by-step instructions on how to do this.

Take extra precautions when working on the fuel system

Gasoline is extremely flammable, so take extra care when working on any part of the fuel system. Do not smoke or allow open flames or bare light bulbs near the work area. Do not work near any gas appliances such as a water heater or clothes dryer. Since gasoline is also carcinogenic, wear latex gloves and rinse off immediately with soap and water if any fuel comes into contact with your skin. Mop up any spills immediately and dispose of fuel-soaked rags properly to avoid the risk of ignition. Keep a Class B type fire extinguisher on hand in case of any accidents.

Be careful with fuel spills

When removing the old fuel filter, be prepared for some fuel to spill out. Have rags or a container ready to catch any spills and dispose of them properly.

Reattach the battery and test your vehicle

Once you have installed the new fuel filter and reconnected the fuel lines, reattach the negative battery terminal and make sure it is secure. Start your GMC and let it idle for a few minutes to ensure everything is running smoothly. Take it for a test drive and check for any fuel leaks around the new filter.

GMC fuel filter housing replacement

To replace the fuel filter housing on a GMC Sierra 2500/3500 HD, follow these steps:

Tools Required:

• Trim fastener removal tool or a flathead screwdriver
• 10mm socket and socket wrench
• Medium-size channel lock style pliers
• Pick tool or a small flathead screwdriver

Step-by-Step Guide:

• Remove the center air intake tube between the air filter housing and the turbocharger.
• Remove the passenger side inner fender. It is held in place by plastic body clips and two 10mm bolts.
• Locate the water-fuel separator drain valve at the bottom of the fuel filter. Open the bleed screw at the top of the fuel filter housing, then open the water separator drain valve to drain the water/fuel into a container.
• Disconnect the water-in-fuel sensor electrical connector.
• Rotate the fuel filter counter-clockwise (from the bottom) and remove it. Keep the filter upright to avoid spilling fuel.
• Drain and dispose of the remaining fuel from the fuel filter.
• Check that the old gasket is not stuck to the fuel filter head.
• Using a wrench, deep socket, or pliers, remove the water-in-fuel sensor assembly from the bottom of the filter.
• If the new fuel filter has an o-ring for the water-in-fuel sensor assembly, replace the old o-ring. Lubricate the new o-ring with clean engine oil before installing.
• Inspect the water in the fuel sensor assembly for any damage. If there is any, replace the assembly with a new one. The old one cannot be reused.
• If the new fuel filter comes with a new gasket, replace the old gasket. Lubricate the new gasket with clean engine oil before installing.
• Install the new fuel filter in the reverse order of removal. Do not fill the new filter with fuel as it will be primed after installation. Ensure the water-in-fuel sensor wire doesn't get tangled. Install by hand only, without tightening with tools.
• Open the bleed valve fuel filter head and pump the plunger on top of the fuel filter housing until all air escapes and fuel starts to flow out of the bleed valve. Close the bleed valve, being careful not to over-tighten it.
• Reinstall the inner fender and intake tube.
• Start the engine and slide underneath the truck to check for leaks. The engine will run rough for the first 30 seconds. If it doesn't smooth out after about a minute, re-bleed the system and repeat the pumping process.

Alternatively, you can replace the entire fuel filter housing as a unit, without having to remove the filter first. This process includes some overlapping steps with the fuel filter replacement procedure outlined above. Here are the additional steps:

• Disconnect the fuel heater wiring harness.
• Disconnect the fuel lines from the filter head using a small angled pliers to release the spring clips. Slide them onto the hose.
• Use a pick tool or small flathead screwdriver to break the fuel hose free from the filter head fuel inlet and outlet.
• Inspect the fuel lines and replace them if they show spiderweb cracks or flat spots. You can use a standard fuel hose instead of a pre-bent hose.
• Remove the 12mm bolts attaching the filter head and remove the fuel filter housing assembly.
• Install the new fuel filter housing in the reverse order of removal. When reinstalling the fuel line, consider replacing the spring clips with stainless steel hose clamps.
• Don't fill the new filter with fuel, as it will be primed after installation.
• Check that the fuel filter is snug in the filter head, doing this by hand only.

If you have any questions or need assistance with the replacement process, don't hesitate to contact a GMC service professional or a trusted mechanic.

GMC fuel filter replacement tools

Replacing the fuel filter on a GMC vehicle is a relatively straightforward process, but it does require some specific tools. The fuel filter is located on the undercarriage of the vehicle, typically on the driver's side, near the fuel tank.

To replace the fuel filter, you will need the following tools and materials:

• New fuel filter (OEM quality or better is recommended)
• Fuel line release tools or a set of line wrenches
• Screwdriver
• Recipe to collect any leaking fuel
• Rags
• Fuel filter socket set (optional)

• Locate the fuel pump relay under the fuse box housing and remove the fuse. The car will run out of fuel, so make sure to do this before starting the replacement process.
• Remove the cap on the pipe attached to the fuel filter to release any remaining pressure. You may need to use a screwdriver to push in on the pipe tab.
• Remove the first and second pipes.
• Use a screwdriver to release the clamp that holds the fuel filter to the vehicle's body.
• Take out the old fuel filter and insert the new one.
• Tighten the clamp to secure the new fuel filter in place.
• Reattach the hoses to the fuel filter and tighten the caps.
• Check for any leakages and then start the engine.

It is important to note that the location of the fuel filter may vary slightly between different GMC models, so it is always a good idea to refer to your owner's manual for specific instructions. Additionally, some GM vehicles require special tools to release the fuel lines, so it is worth checking if you have the correct tools before beginning the replacement process.

Frequently asked questions