L5P Duramax Fuel Tank Pump Module Kit | GM 86534329

Replace a weak or failed L5P in-tank lift pump with the genuine GM module. GM 86534329 is the current OEM fuel tank / fuel pump module kit for 2020–2025 Silverado and Sierra HD trucks with the 6.6L Duramax. It sits in the tank, feeds the high-pressure pump, and includes the fuel-level sender. A failing module can cause hard start, no-start, low supply pressure, a noisy tank, or a fuel gauge that reads wrong. This kit supersedes 84777079, 85105758, and 85557026.

Key features

• Genuine GM / ACDelco OE fuel pump module
• Complete in-tank assembly with pump, sender, and strainer
• Restores factory diesel supply pressure to the high-pressure pump
• Fuel sending unit included for correct gauge operation
• Gasket / seal included
• Direct-fit replacement for the listed crew-cab short-box trucks
• Current GM supersession for earlier L5P module numbers

Fitment

• 2020–2025 Chevrolet Silverado 2500HD 6.6L Duramax L5P
• 2020–2025 Chevrolet Silverado 3500HD 6.6L Duramax L5P
• 2020–2025 GMC Sierra 2500HD 6.6L Duramax L5P
• 2020–2025 GMC Sierra 3500HD 6.6L Duramax L5P
• Crew cab, short box (6 ft 6 in / 6.9 ft bed)
• 3500HD single-tank applications

Does not fit 2017–2019 L5P trucks, gas engines, long-box models, dual-tank setups, or cab-and-chassis tanks. Confirm cab, bed length, and tank count before ordering.

What’s in the box

• GM fuel tank pump module assembly
• Fuel sending unit
• Strainer
• Tank gasket / seal

Lock ring, mounting hardware, and wiring harness are not included. The lock ring is reused only if it is in good condition; GM notes the related seal cannot be reused.

Notes & specs

• Brand/part number: GM 86534329
• Also listed as: ACDelco 86534329
• Type: in-tank electric fuel pump module
• Fuel: diesel
• Voltage: 12V
• Outlet: quick-connect, 0.37 in
• Sender range: 40 ohm full / 250 ohm empty
• Lock ring included: no
• Gasket included: yes
• Strainer included: yes
• Supersedes: 84777079, 85105758, 85557026

Relieve fuel-system pressure, support the tank, and replace the lock-ring seal during install. After start-up, check for leaks and confirm the gauge sweeps correctly. If a 2020–2025 L5P crew-cab short-box truck is starving the CP4 or reading fuel level wrong, GM 86534329 is the OEM in-tank pump module for that tank.