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

Availability
Manufacturer
Make
Model
Year
Price
$0
$27,677.69
Rating
Loading products...
Filter
265 products
Sort by:
Best selling
Availability
Manufacturer
Make
Model
Year
Price
$0
$27,677.69
Rating
PPE 119020010 Engine to CAB Coolant Hose | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 119020010 Engine to CAB Coolant Hose | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

PPE

PPE 119020010 Engine to CAB Coolant Hose | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: PPE119020010
$11.69
Wehrli 100189 Billet Crankcase PCV Vent Fitting Kit | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Wehrli 100189 Billet Crankcase PCV Vent Fitting Kit | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Wehrli 100189 Billet Crankcase PCV Vent Fitting Kit | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Wehrli 100189 Billet Crankcase PCV Vent Fitting Kit | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Wehrli Custom Fab

Wehrli 100189 Billet Crankcase PCV Vent Fitting Kit | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: WCF100189
$44.62
Mahle 54580 Left Side Head Gasket | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Mahle 54580 Left Side Head Gasket | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Mahle

Mahle 54580 Left Side Head Gasket | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: MCI54583
$88.86
$188.38
PPE 168030150 Engine Mount Kit 50 Hardness | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 168030150 Engine Mount Kit 50 Hardness | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 168030150 Engine Mount Kit 50 Hardness | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 168030150 Engine Mount Kit 50 Hardness | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 168030150 Engine Mount Kit 50 Hardness | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

PPE

PPE 168030150 Engine Mount Kit 50 Hardness | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: PPE168030150
$269.99
PPE 114000565 Oil Filter - Micropure Extreme Performance with Torqstop Technology | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 114000565 Oil Filter - Micropure Extreme Performance with Torqstop Technology | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 114000565 Oil Filter - Micropure Extreme Performance with Torqstop Technology | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 114000565 Oil Filter - Micropure Extreme Performance with Torqstop Technology | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 114000565 Oil Filter - Micropure Extreme Performance with Torqstop Technology | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

PPE

PPE 114000565 Oil Filter - Micropure Extreme Performance with Torqstop Technology | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: PPE114000565
$35.99
Mahle SH-1999S SH-1999S Cam Shaft Bearing Set | 2001-2013 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Mahle SH-1999S SH-1999S Cam Shaft Bearing Set | 2001-2013 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Mahle

Mahle SH-1999S SH-1999S Cam Shaft Bearing Set | 2001-2013 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: MCISH-1999S
$80
$245.57
HP Tuners M03-000-04 MPVI3 OBII Scanning and Calibration Tool with 4 Universal Credits
HP Tuners M03-000-04 MPVI3 OBII Scanning and Calibration Tool with 4 Universal Credits
HP Tuners M03-000-04 MPVI3 OBII Scanning and Calibration Tool with 4 Universal Credits
HP Tuners M03-000-04 MPVI3 OBII Scanning and Calibration Tool with 4 Universal Credits
HP Tuners M03-000-04 MPVI3 OBII Scanning and Calibration Tool with 4 Universal Credits

HP Tuners

HP Tuners M03-000-04 MPVI3 OBII Scanning and Calibration Tool with 4 Universal Credits

SKU: HPTM03-000-04
$589.95
Edge 85300 Evolution CS2 | GM/Ford/Dodge Applications
Edge 85300 Evolution CS2 | GM/Ford/Dodge Applications
Edge 85300 Evolution CS2 | GM/Ford/Dodge Applications
Edge 85300 Evolution CS2 | GM/Ford/Dodge Applications
Edge 85300 Evolution CS2 | GM/Ford/Dodge Applications

Edge Products

Edge 85300 Evolution CS2 | GM/Ford/Dodge Applications

SKU: EDG85300
$499.95
ARP 230-4202 Custom Age 625+ Head Stud Kit | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
ARP 230-4202 Custom Age 625+ Head Stud Kit | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

ARP

ARP 230-4202 Custom Age 625+ Head Stud Kit | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: ARP230-4202
$1,727.31
$3,294.60
ARP 129-2503 Harmonic Balancer Bolt Kit | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax V8
ARP 129-2503 Harmonic Balancer Bolt Kit | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax V8

ARP

ARP 129-2503 Harmonic Balancer Bolt Kit | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax V8

SKU: ARP129-2503
$23.92
$45.62
ARP 100-7533 8MM 12pt Valve Cover Bolt Kit | 2004.5-2016 GM 2500HD/3500HD 6.6L Duramax
ARP 100-7533 8MM 12pt Valve Cover Bolt Kit | 2004.5-2016 GM 2500HD/3500HD 6.6L Duramax

ARP

ARP 100-7533 8MM 12pt Valve Cover Bolt Kit | 2004.5-2016 GM 2500HD/3500HD 6.6L Duramax

SKU: ARP100-7533
$116.51
Merchant 10251 Automotive Glow Plug Nuts (Set of 8) | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Merchant 10251 Automotive Glow Plug Nuts (Set of 8) | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Merchant Automotive

Merchant 10251 Automotive Glow Plug Nuts (Set of 8) | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: MAT10251
$4.72
Tuner 1101A021 DSP5 Switch | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Tuner 1101A021 DSP5 Switch | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Duramax Tuner

Tuner 1101A021 DSP5 Switch | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: DMT1101A021
$40
Edge 98654 EAS Shift On The Fly Accessory | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Edge 98654 EAS Shift On The Fly Accessory | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Edge Products

Edge 98654 EAS Shift On The Fly Accessory | 2004.5-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: EDG98654
$274.95
Merchant 13939 Valve Guide Seal | 2001-2010 GM 2500HD/3500HD 6.6L Duramax
Merchant 13939 Valve Guide Seal | 2001-2010 GM 2500HD/3500HD 6.6L Duramax

Merchant Automotive

Merchant 13939 Valve Guide Seal | 2001-2010 GM 2500HD/3500HD 6.6L Duramax

SKU: MAT13939
$1.39
PPE 119000630 Coolant Bypass Tube - Water Pump to Thermostat Housing (Polished) | 2001-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 119000630 Coolant Bypass Tube - Water Pump to Thermostat Housing (Polished) | 2001-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 119000630 Coolant Bypass Tube - Water Pump to Thermostat Housing (Polished) | 2001-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

PPE

PPE 119000630 Coolant Bypass Tube - Water Pump to Thermostat Housing (Polished) | 2001-2005 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: PPE119000630
$116.99
Mahle 54597/54598 Victor Reinz 1.05mm Thick Left & Right Head Gasket | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Mahle 54597/54598 Victor Reinz 1.05mm Thick Left & Right Head Gasket | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Victor Reinz

Mahle 54597/54598 Victor Reinz 1.05mm Thick Left & Right Head Gasket | 2001-2010 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: MCI54597/54598
$220.64
Fleece FPE-HAR-DMAX-CPS-0416 Crankshaft Position Sensor Pigtail | 2004-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Fleece FPE-HAR-DMAX-CPS-0416 Crankshaft Position Sensor Pigtail | 2004-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Fleece FPE-HAR-DMAX-CPS-0416 Crankshaft Position Sensor Pigtail | 2004-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Fleece FPE-HAR-DMAX-CPS-0416 Crankshaft Position Sensor Pigtail | 2004-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Fleece Performance Products

Fleece FPE-HAR-DMAX-CPS-0416 Crankshaft Position Sensor Pigtail | 2004-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: FLCFPE-HAR-DMAX-CPS-0416
$21.99
Mahle 54580 Right Hand Side Head Gasket Grade A | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Mahle 54580 Right Hand Side Head Gasket Grade A | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Mahle

Mahle 54580 Right Hand Side Head Gasket Grade A | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: MCI54580
$88.86
$185.02
PPE 149000135 Heat/Sound Insulator Firewall - Silver | 1999-2007 GM Silverado/Sierra
PPE 149000135 Heat/Sound Insulator Firewall - Silver | 1999-2007 GM Silverado/Sierra
PPE 149000135 Heat/Sound Insulator Firewall - Silver | 1999-2007 GM Silverado/Sierra
PPE 149000135 Heat/Sound Insulator Firewall - Silver | 1999-2007 GM Silverado/Sierra

PPE

PPE 149000135 Heat/Sound Insulator Firewall - Silver | 1999-2007 GM Silverado/Sierra

SKU: PPE149000135
$269.99
PPE 119000500 Engine Coolant Thermostat Housing | 2001-2007 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 119000500 Engine Coolant Thermostat Housing | 2001-2007 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 119000500 Engine Coolant Thermostat Housing | 2001-2007 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

PPE

PPE 119000500 Engine Coolant Thermostat Housing | 2001-2007 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: PPE119000500
$269.99
PPE 118034250 Harmonic Balancer Bolt 12 Point | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 118034250 Harmonic Balancer Bolt 12 Point | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 118034250 Harmonic Balancer Bolt 12 Point | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

PPE

PPE 118034250 Harmonic Balancer Bolt 12 Point | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: PPE118034250
$26.99
PPE 114052001 14mm Billet Hardened Stainless Steel Magnetic Drain Plug for OEM & PPE Engine Oil Pans | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 114052001 14mm Billet Hardened Stainless Steel Magnetic Drain Plug for OEM & PPE Engine Oil Pans | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

PPE

PPE 114052001 14mm Billet Hardened Stainless Steel Magnetic Drain Plug for OEM & PPE Engine Oil Pans | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: PPE114052001
$17.99
PPE 113061064 Dual Fueler Idler Pulley 4 inch Diameter | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 113061064 Dual Fueler Idler Pulley 4 inch Diameter | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
PPE 113061064 Dual Fueler Idler Pulley 4 inch Diameter | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

PPE

PPE 113061064 Dual Fueler Idler Pulley 4 inch Diameter | 2001-2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

SKU: PPE113061064
$31.49

FREE SHIPPING ON ALL
ORDERS OVER $70

PRICE MATCH GUARANTEE

BUILD NOW, PAY LATER
FINANCING OPTIONS

30-DAY RETURN SATISFACTION GUARANTEE

DIESEL TRUCK EXPERTS STANDING BY

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

Can We Help You Find Something?

Give us a call: +1-208-719-7400

Chat With Us
THE GARAGE

The Garage

Welcome to The Garage – your one-stop shop for all your car care and maintenance needs. From premium oils and filters to top-notch car care products, we have everything you need to keep your vehicle running smoothly and looking its best. Whether you're a DIY enthusiast or a professional mechanic, our carefully curated selection of high-quality products will help you take care of your ride like never before.

Shop The Garage