2007 Mercedes GL450 Fuel Pump Location: A Complete Owner's Guide

The bottom line up front: On a 2007 Mercedes GL450, the fuel pump is located inside the fuel tank, which sits beneath the vehicle near the rear axle. To physically access the pump assembly, you must remove the rear seats from inside the cabin, peel back the floor mat, and open a round access cap sealed to the body. The powered fuel pump module is on the passenger side, while the driver's side unit is a passive suction jet pump that uses the Venturi effect to move fuel.

This guide walks you through the exact location, how to access it safely, what tools you need, and what to expect when replacing the pump on your 2007 GL450. We also cover common symptoms of a failing pump, the typical cost of replacement, and a reliable aftermarket option if you decide to do the job yourself.

Where Exactly Is the Fuel Pump on a 2007 GL450?

The fuel pump on the 2007 Mercedes GL450 is not under the hood. It is mounted inside the fuel tank, which is positioned beneath the rear of the vehicle. From inside the cabin, the access point is under the rear seat area. Here is the breakdown:

  1. Passenger side rear seat – The main electric fuel pump module is located on the passenger side of the fuel tank. This is the component that actually pressurizes fuel and sends it to the engine.
  2. Driver side rear seat – The driver's side contains a fuel filter and pressure regulator assembly, not a powered pump. This side uses a suction jet pump that operates on the Venturi principle, drawing fuel from the lower part of the tank using the flow of returning fuel.

To see the top of the pump assembly, you must remove the rear seats. Specifically, you need to take out the 40% seat (rear passenger side) and slide the 60% seat forward to access the driver's side cap.

How to Access the Fuel Pump: Step-by-Step

Accessing the fuel pump on a 2007 GL450 is a involved process that requires patience and the right tools. Here is what you need to do in order:

Step 1: Disconnect the battery

Before doing anything, disconnect the negative battery cable. This reduces the risk of accidental electrical discharge or sparks while working around fuel system components.

Step 2: Remove the rear seat flaps and bottom covers

On the rear passenger side, locate the flaps at the base of the seat. These are held in place by tabs, not screws. Be careful when releasing them, as the tabs can break easily. Once removed, you will see the underlying cover and the bolts securing the seat.

Step 3: Disconnect SRS cables and remove the rear seats

There are two hex nuts and several Torx bolts holding each rear seat in place. Before lifting the seat out, disconnect the SRS (Supplemental Restraint System) cable. There is one cable per seat. Once disconnected, you can lift the 40% seat out of the vehicle. The 60% seat is heavy, so slide it over to the open side rather than lifting it out completely.

Step 4: Locate and open the access cap

Fold back the floor mat on the driver's side corner. You will see a round cap covering the access hole. This cap is attached to the body with sealant only. Remove the sealant and lift the cap off. Now you can see the top of the fuel pump module.

Step 5: Document the connections

Before disconnecting anything, take a picture of the pump top. This will help you reconnect the fuel lines and electrical connectors correctly during installation.

What Tools and Parts Do You Need?

To remove the fuel pump on a 2007 GL450, gather the following items:

  • Jack and jack stands – You may need to raise the vehicle, depending on how much access you have.
  • Socket set – For removing the rear seat bolts and any tank straps.
  • T25 Torx spline wrench – For removing the fuel pump cover plate.
  • 17mm socket wrench – For the fuel pump strainer/filter retaining ring.
  • Screwdriver – For releasing the electrical connector clips.
  • Fuel line disconnect tool – For safely separating the quick-connect fittings.
  • Drain pan – To catch residual fuel in the lines and pump reservoir.
  • New fuel pump module – The OE part number for the 2007 GL450 is 1644701994. This module includes the electric pump, filter, pressure regulator, and fuel level sender in one assembly.

Safety First: Relieving Fuel Pressure

Before disconnecting any fuel lines, you must relieve the pressure in the fuel system. The recommended way to do this is:

  1. Disconnect the fuel pump relay or fuse.
  2. Start the engine and let it run until it stalls from lack of fuel.
  3. Crank the engine for a few more seconds to clear any remaining pressure.

This step minimizes fuel spillage when you open the tank and disconnect the lines. Also, be aware that fuel in the tank cools and lubricates the pump, so try to keep the tank at least a quarter full after installing a new pump to maximize its lifespan.

Removing the Old Fuel Pump

Once you have access and the fuel pressure is relieved, follow these steps:

  1. Remove the fuel pump cover plate – Use the T25 Torx wrench to remove the locking ring or cover plate.
  2. Disconnect the fuel lines and electrical connector – Use the fuel line disconnect tool to separate the quick-connect fittings. Unplug the electrical connector from the top of the pump module.
  3. Lift the pump out – Carefully lift the old fuel pump assembly straight up. Do not tilt it more than 45 degrees, or fuel from the pump reservoir will spill.

Important: On these Mercedes models, the fuel pump module is replaced as a complete assembly. You cannot just replace the pump itself, because the module houses the pump, filter, pressure regulator, and fuel level sender as a single sealed unit.

Installing the New Fuel Pump

Installing the new pump is the reverse of removal, but you need to pay close attention to detail:

  1. Clean the area – Wipe down the tank opening and mounting surface with a lint-free cloth and isopropyl alcohol to remove dirt and residue.
  2. Seat the new pump – Align the pump assembly with the tank's mounting points. Ensure the rubber gasket or seal is properly seated to create an airtight connection.
  3. Replace the locking ring – Torque the retaining bolts to the manufacturer's specification, typically 10 to 15 Nm. Do not over-tighten, as this can crack the tank or damage the pump.
  4. Reconnect the fuel lines – Press the quick-connect fittings until they click securely into place. Inspect the hoses for cracks or brittleness and replace them if needed.
  5. Reconnect the electrical connector – Make sure it is fully seated to prevent shorts or disconnections.
  6. Seal the access cap – Apply body sealant around the cap and press it back into place.
  7. Reinstall the rear seats – Bolt the seats back down, reconnect the SRS cables, and reinstall the trim flaps.
  8. Reconnect the battery – Restore power to the vehicle.

Testing the Installation

After everything is back together, test the system:

  1. Cycle the ignition – Turn the key to the "on" position without starting the engine. This activates the fuel pump and pressurizes the system. Do this a few times.
  2. Check for leaks – Use a spray bottle with soapy water on all connections. If you see bubbles, there is a leak that needs to be addressed.
  3. Start the engine – Listen for unusual noises from the fuel tank area. A properly installed pump should operate quietly and maintain consistent fuel pressure.

Common Symptoms of a Failing Fuel Pump on the 2007 GL450

Knowing the location of the pump is only half the battle. You also need to recognize when it is failing. Common symptoms include:

  • Engine cranks but won't start – This is the most obvious sign of pump failure.
  • Loss of power during acceleration – The pump cannot deliver enough fuel pressure under load.
  • Engine sputters or stalls at highway speeds – Inconsistent fuel delivery causes hesitation and stalling.
  • Whining noise from the fuel tank – A loud buzzing or whining sound that changes with engine speed indicates the pump is struggling.
  • Poor fuel economy – A weak pump causes the engine to run inefficiently.

If you experience any of these symptoms, check the fuel pump before assuming it is something else. A professional mechanic will test fuel pressure at the injectors and verify the pump's electrical circuit before condemning the pump itself.

Replacement Cost for a 2007 GL450 Fuel Pump

The cost of replacing the fuel pump on a 2007 GL450 varies depending on where you have the work done:

  • Dealership replacement – Can cost upwards of $2,300.
  • Independent shop – The average cost for a GL450 fuel pump replacement is between $1,026 and $1,307.
  • DIY replacement – You can save significantly by doing the job yourself. The parts cost for a fuel pump module ranges from $45 to $80 for aftermarket options, but you will need to factor in the time and tools required.

The labor is the expensive part. Accessing the pump requires removing the rear seats, which adds several hours to the job.

A Smart Choice: KEMSO Fuel Pump for Your 2007 GL450

If you are planning to replace the fuel pump on your 2007 Mercedes GL450, you need a part that delivers reliable performance without breaking the bank. That is where KEMSO comes in.

KEMSO fuel pumps are engineered to meet or exceed original equipment specifications. Each pump is built as a direct OEM replacement, meaning it bolts in exactly where the factory pump came out. No modifications, no guesswork, no fitment issues.

Here is what you get with a KEMSO fuel pump:

  1. High-performance construction – KEMSO pumps are designed to deliver consistent fuel pressure under all driving conditions, ensuring your GL450 starts quickly and runs smoothly.
  2. True OEM replacement fitment – Every pump is manufactured to match the original dimensions, electrical connections, and flow characteristics of the factory pump.
  3. Lifetime warranty – KEMSO stands behind its products with a lifetime warranty. If the pump ever fails, you are covered.

Whether you drive a Mercedes GL450 or any other vehicle, KEMSO has a fuel pump engineered for your application. Their product lineup covers cars, trucks, motorcycles, and watercraft, all with the same commitment to quality and durability.

Visit KEMSO today at https://www.kemsoracing.com/ to find the right fuel pump for your 2007 Mercedes GL450. With KEMSO, you get a high-performance replacement at a fraction of the dealership cost, backed by a lifetime warranty.

Final Thoughts

The 2007 Mercedes GL450 fuel pump is located inside the fuel tank, accessed through the rear seat area of the cabin. The main electric pump is on the passenger side, while the driver's side houses a passive suction jet pump and pressure regulator. Replacing the fuel pump module is a complex job that requires removing the rear seats, relieving fuel pressure, and carefully handling fuel system components.

If you are comfortable with automotive repairs and have the right tools, this is a doable DIY project. If not, factor in the labor cost from a professional mechanic. Either way, use a quality replacement pump like KEMSO to ensure your GL450 stays on the road for years to come.

For more information and to purchase a KEMSO fuel pump for your vehicle, visit https://www.kemsoracing.com/


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