Exergy 17-24 Chevrolet Duramax 6.6L L5P Denso HP4 Pump
The 6.6L L5P Duramax in 2017-2024 Chevrolet Silverado and GMC Sierra 2500 HD and 3500 HD trucks uses a Denso HP4 high pressure pump to feed its common rail. When that pump wears, the truck loses rail pressure, starts hard or stalls, and in a bad failure it can push debris into the injectors. The Exergy E04 10702 is a new Denso stock replacement HP4 that Exergy builds with upgraded internal bushings, aimed at the low lubricity fuel that shortens factory pump life.
The low pressure side delivers filtered diesel to the HP4. A metering valve on the pump decides how much of that fuel enters the pumping chambers, and the pump raises it to rail pressure for the eight injectors, with the engine computer adjusting the amount to hit the rail pressure it wants. Like other modern common rail pumps, the HP4 is lubricated and cooled by the fuel passing through it. Poor lubricity, water or air in the supply speeds up wear on the internal bearing surfaces. Exergy says its upgraded bushings resist low lubricity fuel and give a longer service life than the original pump, based on years of in-house testing.
Log desired and actual rail pressure together with low side supply pressure. If supply pressure is steady and rail pressure still cannot keep up, the high pressure side is the problem. Change the fuel filter and cut the old one open. Metal means internal pump wear, and the injectors and fuel lines downstream need inspection. Water in the filter points to the root cause. A truck that drops into reduced power with no fuel codes may have a transmission fault instead. On 2017-2019 trucks with the Allison 1000, start with our Allison 1000 limp mode guide.
Exergy lists E04 10702 for 2017 through 2024 Chevrolet Silverado 2500 HD and 3500 HD and GMC Sierra 2500 HD and 3500 HD with the 6.6L L5P Duramax. Exergy states it directly replaces GM 12678993 and 12701094, Denso 294050-0701, Alliant Power AP54850 and AP54851, and International 6040608C91. Compare the number on your pump, or send us your year and VIN to confirm before ordering. More parts for these trucks are on our Allison 1000 parts page and in the engine and fuel parts category.
If you are servicing the transmission while the truck is down, see our Allison 1000 service guide and the L5P cooler line kit.
| Brand | Exergy |
| Part number | E04 10702 |
| Fits | Exergy 17-24 Chevrolet Duramax 6.6L L5P Denso HP4 Pump |
| Vehicle fitment | Chevrolet Duramax (2017-2024) |
| Type | Injection Pumps & Controllers |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Yes. Exergy lists E04 10702 for 2017 through 2024 Silverado and Sierra 2500 HD and 3500 HD with the 6.6L L5P Duramax. Confirm with your year and VIN if you are unsure.
Exergy lists it as a direct replacement for GM 12678993 and 12701094, Denso 294050-0701, Alliant Power AP54850 and AP54851, and International 6040608C91.
No. It is a new Denso stock replacement pump with Exergy's upgraded internal bushings.
No. It is a stock replacement unit for the L5P, so a stock truck needs no tuning changes.
Always replace the fuel filter and drain any water. If the old pump shed metal, the injectors, rails and high pressure lines also need to be cleaned or replaced.
P0087 fuel rail pressure too low is the most common. Confirm with a scan tool by logging desired versus actual rail pressure and low side supply pressure.
