How to Replace the Fuel Pump on a 2012 GMC Sierra 1500
Step-by-step in-tank fuel pump module replacement with tools, parts, torque specs, and safety tips for 2009, 2010, 2011, 2012, 2013
How to Replace the Fuel Pump on a 2012 GMC Sierra 1500
Step-by-step in-tank fuel pump module replacement with tools, parts, torque specs, and safety tips for 2009, 2010, 2011, 2012, 2013
🔧 Fuel Pump - Replacement
Your Sierra uses an in-tank fuel pump module, so the repair means relieving fuel pressure, lowering the fuel tank, and swapping the pump assembly. This is a messy, flammable repair, so take your time and work safely. A clean workspace and a nearly empty tank make the job much easier.
Difficulty Level: Advanced | Estimated Time: 4-6 hours
⚠️ Safety & Precautions
- Work outside or in a very well-ventilated area. Fuel vapors are dangerous.
- No smoking, sparks, open flames, heat guns, or drop lights near the fuel system.
- Relieve fuel pressure before disconnecting any fuel lines.
- Disconnect the negative battery cable before starting. Reconnect only after all fuel lines are secured.
- Use approved fuel-safe drain containers if the tank must be emptied.
- Support the fuel tank with a transmission jack or floor jack before removing straps.
- Keep a class B fire extinguisher nearby.
🔧 Required Tools
You'll need the following tools for this repair:
- 3/8-inch drive ratchet
- 10mm socket
- 13mm socket
- 15mm socket
- Fuel line disconnect tool set (specialty)
- Flat-blade screwdriver
- Pliers
- Torque wrench
- Floor jack (rated 3-ton minimum)
- Jack stands (rated for truck weight)
- Transmission jack or wide jack saddle
- Drain pan
- Shop towels
- Safety glasses
- Nitrile gloves
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Fuel pump module assembly - Qty: 1
- Fuel tank module seal/gasket - Qty: 1
- Fuel pump locking ring - Qty: 1
- Fuel filter - Qty: 1
- Fuel tank strap bolts - Qty: 2
- Fuel line O-rings/clips - Qty: As needed
- Fuel tank - Qty: 1
- Fuel injector-safe cleaner - Qty: 1 can
📋 Before You Begin
- Run the tank as low as safely possible before starting. A nearly empty tank is much lighter and easier to lower.
- Park on level ground and set the parking brake.
- Disconnect the negative battery cable using a 10mm socket.
- Relieve fuel system pressure at the fuel rail service port if equipped, or by following the key-off pressure bleed procedure for this truck.
- Support the truck securely on jack stands before working underneath it.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Relieve fuel pressure and disconnect the battery
- Use a 10mm socket to disconnect the negative battery cable.
- Relieve fuel pressure before opening any fuel line.
- Wrap shop towels around fittings.
Step 2: Raise and support the truck
- Use a floor jack to raise the rear of the truck, then support it with jack stands.
- Make sure the truck is stable before crawling underneath.
Step 3: Remove the fuel tank shield and disconnect hoses
- Use a 13mm socket or 15mm socket to remove any skid plate or shield hardware, if equipped.
- Disconnect the filler neck hose, vent hoses, and evap lines with pliers and a flat-blade screwdriver as needed.
- Use the fuel line disconnect tool set (specialty) to separate the fuel supply and return lines.
- Label hoses before removal.
Step 4: Support the fuel tank
- Place a transmission jack or wide jack saddle under the tank.
- Raise it slightly so the tank is supported but not lifted.
Step 5: Remove the tank straps
- Use a 15mm socket to remove the tank strap bolts.
- Lower the straps carefully and keep them positioned for reinstallation.
- Torque on installation: Torque strap bolts to 25 Nm (18 ft-lbs).
Step 6: Lower and remove the fuel tank
- Slowly lower the tank with the jack while watching for any still-connected hoses or wires.
- Disconnect the electrical connector to the pump module once it is accessible.
- Lower the tank fully and slide it out from under the truck.
Step 7: Replace the fuel pump module
- Clean the top of the tank with shop towels before opening it.
- Use a flat-blade screwdriver and brass drift or locking ring tool to remove the locking ring, if equipped.
- Lift out the old fuel pump module carefully.
- Install the new fuel tank module seal/gasket and the new pump module.
- Install the locking ring and seat it fully.
- Keep dirt out of the tank.
Step 8: Reinstall the fuel tank
- Raise the tank back into position with the transmission jack or wide jack saddle.
- Reconnect the electrical connector and all fuel/EVAP lines.
- Install the tank straps and tighten with a 15mm socket.
- Torque tank strap bolts to 25 Nm (18 ft-lbs).
Step 9: Reconnect hoses, shield, and battery
- Reconnect the filler neck, vent hoses, and fuel lines using the fuel line disconnect tool set (specialty) where needed.
- Reinstall any shield or skid plate with a 13mm socket or 15mm socket.
- Reconnect the negative battery cable with a 10mm socket.
Step 10: Prime and check for leaks
- Turn the key to ON for 2-3 seconds, then OFF. Repeat 3-4 times to prime the system.
- Start the engine and inspect all fuel connections for leaks.
- Torque any access cover fasteners to snug fit if applicable; do not overtighten plastic parts.
✅ After Repair
- Let the engine idle for a few minutes and confirm smooth operation.
- Check under the truck for fuel seepage after the first drive.
- If the engine cranks longer than normal, cycle the key ON/OFF again to finish priming.
- If a check engine light is present, scan for fuel pressure or evaporative system codes.
💰 DIY vs Shop Cost
Shop Cost: $900-$1,500 (parts + labor)
DIY Cost: $250-$550 (parts only)
You Save: $650-$950 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 4-6 hours.
🎯 Ready to get started?
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