Exergy 01-04 Chevrolet Duramax 6.6L LB7 Sportsman CP3 Pump (LBZ Based w/FCA)
This is the pump for a 2001-2004 Chevrolet Silverado or GMC Sierra 2500 HD or 3500 with the LB7 Duramax that is losing rail pressure, cranking long before it fires, or falling on its face under load because the original CP3 is worn out. The Exergy Sportsman E04 10105 is a new, upgraded replacement pump, not a rebuilt core, and it is built for stock trucks and mild builds up to roughly 650 horsepower without needing a big lift pump or a custom tune to run it.
The LB7 was GM's first common-rail Duramax, and the CP3 is the gear-driven high-pressure pump that feeds both fuel rails. Low-pressure fuel arrives from the tank, the pump's internal gear stage pressurizes it, and three radial plungers push it to rail pressure. A fuel control actuator (FCA) on the pump meters how much fuel those plungers receive, which is how the engine computer holds the pressure it commands. When the plungers or valves wear, the pump can no longer reach target, and the computer cuts fuel to protect the engine.
Exergy builds this LB7 version on its LBZ-based pump body and fits it with an LB7 fuel pressure regulator so the factory calibration controls it without extra tuning work. Exergy says this pump is for LB7 applications only. Compared with a stock pump, the Sportsman uses higher-flowing valves, DLC-coated plungers that resist scoring, and more bearing surface to carry the pumping load. Exergy also notes that a stock CP3 stops adding flow at about 3,000 RPM, while the Sportsman keeps climbing past that point.
The LB7 is famous for injector failures, and a leaking injector can drain rail pressure just like a tired pump. Before you spend money here, log desired versus actual rail pressure, run an injector balance rate or return-flow test, and check fuel filter restriction and supply pressure. If the injectors are returning too much fuel, a new pump will only mask the problem. Also be sure the complaint is really fuel: a truck that flares or feels weak on a hill can be an Allison slipping. Our Allison 1000 limp mode guide walks through the transmission side so you can rule it out.
Exergy lists the E04 10105 for 2001, 2002, 2003 and 2004 Chevrolet Silverado 2500 HD and 3500, and GMC Sierra 2500 HD and 3500, with the 6.6L LB7. It replaces Bosch numbers 0 445 020 017, 0 445 020 005 and 0 986 437 303, and GM numbers 97208073 and 97720662. If your truck is a 2004.5-2005 with the LLY, this is not your pump. The quickest check is the eighth digit of the VIN, which is 1 on an LB7. When in doubt, send us the year and VIN before you order. Every Duramax and Allison part we carry is grouped under engine performance and the Allison 1000 parts page.
Restoring full rail pressure brings back the torque the Allison was used to, so it is a good time to service it. Our Allison 1000 fluid and filter specs cover what to use.
| Brand | Exergy |
| Part number | E04 10105 |
| Fits | Exergy 01-04 Chevrolet Duramax 6.6L LB7 Sportsman CP3 Pump (LBZ Based w/FCA) |
| Vehicle fitment | Chevrolet Duramax (2001-2004) |
| Type | Injection Pumps & Controllers |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Only if it is a 2001-2004 LB7. A 2004.5-2005 truck has the LLY engine and needs a different pump. Check the eighth VIN digit: 1 means LB7. Send us the VIN if you are not sure.
Exergy builds the LB7 Sportsman on its LBZ pump body and adds an LB7 fuel pressure regulator so the stock LB7 calibration can control it. Exergy says it should only be used on LB7 engines.
No. Exergy says the Sportsman runs without significant supporting mods or tuning. For maximum output it recommends a fuel supply of 150 GPH at 8-10 psi.
No. This is a new pump with no core charge and no core to send back.
No. Leaking injectors, a plugged fuel filter, air in the supply side or a bad FCA can all drop rail pressure. Test injector return and supply pressure before replacing the CP3.
A new fuel filter at minimum. If the old pump failed with debris, flush the rails and lines, and test the injectors. A supply pump helps the new CP3 reach full flow.
