2004.5-2005 GM 2500HD/3500HD 6.6L LL Duramax Engine & Performance

2004.5-2005 6.6L Silverado & Sierra 2500HD/3500HD

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Crate Engines

Crate Engines

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Gaskets, Gasket Kits & Bearings

Gaskets

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Glow Plugs

Glow Plugs

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Head Studs & Main Studs

Head Studs & Main Studs

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Heads & Valve Train

Heads & Valve Train

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Motor Mounts

Motor Mounts

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Oil Pans

Oil Pans

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Radiators & Cooling Upgrades

Radiators & Cooling Upgrades

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Rebuild Kits & Internal Parts

Rebuild Kits & Internal Parts

2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Rods, Pistons, Cams & More

Rods/Pistons/Cams & More

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Tuner DT8120010107000 Optimized Stock Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010107000 Optimized Stock Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010107000 Optimized Stock Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010107000
$808
Tuner DT8120010106000 Heavy Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010106000 Heavy Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010106000 Heavy Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010106000
$808
Tuner DT8120010105000 Light Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010105000 Light Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010105000 Light Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010105000
$808
Tuner DT8120010103000 Sport Tune incl EFI Live Spade Sport Tune | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010103000 Sport Tune incl EFI Live Spade Sport Tune | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010103000 Sport Tune incl EFI Live Spade Sport Tune | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010103000
$808
Tuner DT1120010107009 Optimized Stock Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010107009 Optimized Stock Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010107009 Optimized Stock Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010107009
$808
Tuner DT1120010106009 Heavy Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010106009 Heavy Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010106009 Heavy Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010106009
$808
Tuner DT1120010104009 Street Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010104009 Street Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010104009 Street Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010104009
$808
Tuner DT1120010105009 Light Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010105009 Light Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010105009 Light Tow Tune incl EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010105009
$808
Tuner DT1120010103009 Sport Tune incl EFI Live Spade Sport Tune | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010103009 Sport Tune incl EFI Live Spade Sport Tune | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010103009 Sport Tune incl EFI Live Spade Sport Tune | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010103009
$808
Tuner DT8120010001000 Switch on the Fly Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010001000 Switch on the Fly Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010001000 Switch on the Fly Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010001000
$550
Tuner DT1120010001009 Switch on the Fly Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010001009 Switch on the Fly Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010001009 Switch on the Fly Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010001009
$550
Tuner DT8120010007000 Optimized Stock Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010007000 Optimized Stock Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010007000 Optimized Stock Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010007000
$300
Tuner DT8120010006000 Heavy Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010006000 Heavy Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010006000 Heavy Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010006000
$300
Tuner DT8120010004000 Street Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010004000 Street Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010004000 Street Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010004000
$300
Tuner DT8120010005000 Light Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010005000 Light Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010005000 Light Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010005000
$300
Tuner DT8120010003000 Sport Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT8120010003000 Sport Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT8120010003000 Sport Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT8120010003000
$300
Tuner DT1120010007009 Optimized Stock Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010007009 Optimized Stock Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010007009 Optimized Stock Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010007009
$300
Tuner DT1120010006009 Heavy Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010006009 Heavy Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010006009 Heavy Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010006009
$300
Tuner DT1120010005009 Light Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010005009 Light Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010005009 Light Tow Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010005009
$300
Tuner DT1120010004009 Street Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010004009 Street Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010004009 Street Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010004009
$300
Tuner DT1120010003009 Sport Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Tuner DT1120010003009 Sport Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Duramax Tuner

Tuner DT1120010003009 Sport Tune Only for EFI Live Spade | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: DMTDT1120010003009
$300
Edge 98655 EAS Shift On The Fly Accessory | 2001-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7
Edge 98655 EAS Shift On The Fly Accessory | 2001-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7

Edge Products

Edge 98655 EAS Shift On The Fly Accessory | 2001-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7

SKU: EDG98655
$299.95
PPE 119023100 Green Upper & Lower Coolant Hose Kit | 2001-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 119023100 Green Upper & Lower Coolant Hose Kit | 2001-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

PPE

PPE 119023100 Green Upper & Lower Coolant Hose Kit | 2001-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: PPE119023100
$269.99
Sinister SD-EGRC-LLY Upgraded EGR Cooler | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Sinister SD-EGRC-LLY Upgraded EGR Cooler | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Sinister SD-EGRC-LLY Upgraded EGR Cooler | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Sinister SD-EGRC-LLY Upgraded EGR Cooler | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY
Sinister SD-EGRC-LLY Upgraded EGR Cooler | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

Sinister Diesel

Sinister SD-EGRC-LLY Upgraded EGR Cooler | 2004.5-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LLY

SKU: SINSDEGRCLLY
$369.99

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2004.5-2005 6.6L Silverado & Sierra 2500HD/3500HD

Power Lift Shop All

The 6.6L Duramax LLY under the hood of your 2004.5-2005 GM Sierra/Silverado 2500/3500 may be one of the best and most efficient engines out there, but even the toughest trucks have some power and performance waiting to be unleashed through various performance modifications. Here at Alligator Performance, we carry a selection of cold air intakes, tuners, fuel upgrades, and turbo upgrades to help you get the most out of your diesel engine. Many of these upgrades like the cold air intakes and fuel upgrades even help promote component longevity so you can enjoy long-lasting and consistent performance without compromise. After you've added a few engine upgrades to your custom build, be sure to check out our premium 2004.5-2005 GM 6.6L Duramax LLY Transmission Upgrades to compliment the increase in power you're throwing down! GM Duramax Fitments: 2004, 2005 GM 6.6L Duramax. Submodel Fitments: WT, Custom, LT, LTZ, High Country, 1LT, 2LT, Pro, SLE, SLT, AT4, Denali. Some exceptions apply, please see individual product pages for specific fitments.

GM Duramax>2004.5-2005 6.6L LLY
Tuners & Monitors
Cooling Upgrades
Head Studs & Main Studs
Rods, Pistons & Cams
Heads & Valve Train

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