Fuel Pump

In-tank fuel pump replacement on the 2003-2009 GX470 requires removing the fuel tank. The factory sequence starts inside the cabin: the left second-row seat and trim come out to reach a floor service hole, where the pump connector is disconnected before the truck ever goes on a lift. The tank is then drained, unstrapped, and lowered; the pump assembly comes out of the tank top with a ring-wrench retainer. No exhaust components are involved. There is no factory floor access large enough to change the pump without dropping the tank.

Warnings

Tools required

Parts

• Fuel pump
• Suction plate gasket
• Retainer ring
• E-rings (2)
• Tank cushions (3)
• Tank-to-filler-pipe hose

Preparation

1. Cool engine. Ventilated space, no ignition sources.
2. Fuel level as low as possible before starting — siphoning time is part of this job.

Procedure

1. 1

   Remove the left second-row seat and interior trim
   This job starts inside the cabin, not under the truck. Remove the left rear No.1 seat assembly, the rear floor step cover, the inside quarter scuff plate (2 bolts), and the rear door scuff plate. Peel back the rear floor carpet to expose an oval steel cover in the floor above the fuel tank.
2. 2

   Open the floor service hole and disconnect the pump connector
   Remove the three screws securing the rear floor service hole cover and lift it out. Disconnect the fuel pump harness connector through the opening. This connector must be disconnected from inside the cabin before the tank comes down — it is the reason the interior comes apart first.
3. 3

   Depressurize the fuel system and disconnect the battery
   With the pump connector disconnected, start the engine and let it run until it stalls from fuel starvation, then crank it briefly two or three more times. Turn the ignition off and disconnect the negative battery cable.
   ⚠️Residual fuel remains in the lines after depressurizing. Keep shop towels ready at every connection.
4. 4

   Drain the fuel tank
   After disconnecting the filler hose in the next step, drain the fuel tank completely through the filler pipe before lowering the tank. Never lower a full tank. A full tank holds well over a hundred pounds of fuel and cannot be lowered safely.
   ⚠️Never attempt to lower a full or mostly-full tank. Drain first, every time.
5. 5

   Disconnect the filler hose at the filler pipe
   Under the vehicle, disconnect the tank-to-filler-pipe hose at the filler pipe side. Plan on installing a new hose during reassembly — this hose is a non-reusable part and must be aligned to its location marking within 3 mm.
6. 6

   Remove the fuel tank protector
   Support the fuel tank protector with a transmission jack, remove its six bolts, and remove it clear. Set it aside. This is the tank protector, not an exhaust heat shield — no exhaust components are disturbed anywhere in this job.
7. 7

   Release the fuel line quick-connectors
   Release the main tube, return tube, and breather tube quick-connectors by hand only: pinch and rotate each retainer to unlock, then pull the tube straight out. Never use tools on these fittings, never bend the nylon lines, and cap or bag every open joint immediately. If a connector is stuck, work the retainer gently — do not pry.
8. 8

   Disconnect the tank vent hose
   Push the vent connector slightly inward, pinch the release, and pull it free.
9. 9

   Support the tank and remove the tank bands
   Position the transmission jack under the tank and take its weight. Remove the two band bolts — one per band; the opposite ends of the bands locate on pins — and swing the bands down and clear.
10. 10

    Lower and remove the tank
    Lower the jack slowly, checking that every line and connector is free as the tank comes down. Roll the tank out to a ventilated work area.
11. 11

    Clean the suction plate area
    Before opening the tank, clean the top of the tank around the suction plate thoroughly. Any grit that falls into the tank stays in the tank.
12. 12

    Remove the retainer ring with the ring wrench
    The plastic retainer requires Toyota ring wrench SST 09808-14020 or an equivalent that engages the ribs. Unscrew it and lift it off. The retainer is a non-reusable part.
13. 13

    Remove the pump and gauge assembly
    Lift the fuel suction with pump and gauge tube assembly out of the tank, tilting carefully so the sender gauge arm is not bent. Remove and discard the plate gasket.
14. 14

    Transfer the new pump into the assembly
    On the bench, release the plastic claws to separate the sub-tank, suction support, and filter from the plate — use a taped screwdriver tip and work gently; the claws are the assembly. Swap in the new pump with a new O-ring (wipe it with clean gasoline first), reconnect its harness, and rebuild the stack with new E-rings on the suction plate posts.
15. 15

    Install the assembly with a new gasket and retainer
    Set a new gasket on the tank, lower the assembly in with the plate spline indexed into the tank keyway, and start a NEW retainer with its mark aligned to the thread starting point. Tighten one full turn by hand, then one more full turn with the ring wrench so the mark lands inside the index range on the tank.
16. 16

    Reinstall the tank
    Fit new tank cushions, raise the tank on the jack, and secure the two bands with their bolts torqued to 30 ft-lbf. Reconnect the main, return, breather, and vent connectors — push each until it clicks, then pull-check every one.
17. 17

    Refit the protector and a new filler hose
    Reinstall the tank protector with its six bolts at 15 ft-lbf. Install a NEW tank-to-filler-pipe hose, aligned to its location marking within 0-3 mm, and secure the clamps.
18. 18

    Leak-check, then close up the interior
    Reconnect the pump connector through the floor service hole and the battery. Cycle the key several times without starting to pressurize the system, then start the engine and inspect every joint you touched. Only after a clean leak check: reinstall the service hole cover (three screws), carpet, scuff plates, step cover, and the seat with its bolts at 27 ft-lbf.

Verification

• No fuel odor or seepage at any joint after several key cycles and a run-up.
• Fuel gauge reads correctly.
• No check-engine light after a short drive.