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UnderDog Diesel » 2021, Sierra 3500
Products for:
- Year: 2021
- Model: Sierra 3500
View Universal items for: 2021 Sierra 3500
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Description: Fits; 2011-2025 Chevy/GMC 2500/3500 HD Truck
Item #: KR1025
Condition:
New
Price: $9.99
Sale: $9.49
Save: 5%
Save: $0.50
Description: Fits; Most all 8 Lug GM Trucks (Front end) from 2011-2024
Item #: KRP0179
Condition:
New
Price: $12.99
Sale: $12.34
Save: 5%
Save: $0.65
Description: To install this drop in compressor wheel, turbocharger removal is REQUIRED!!!
Item #: VSE-L5P-FTR-WHL
Condition:
New
Price: $499.99
Description: Actuator Included
Airflow to support 700HP
Up to 650 RWHP with stock emissions equipment and basic supporting mods
Tested in competition setups with extensive supporting mods to make 700+ RWHP
41 psi boost @ Sea Level
Item #: DM1MO1070203010
Condition:
New
Price: $3,700.00
Description: Actuator Not Included
Airflow to support 700HP
Up to 650 RWHP with stock emissions equipment and basic supporting mods
Tested in competition setups with extensive supporting mods to make 700+ RWHP
41 psi boost @ Sea Level
Item #: DM1MO1070203000
Condition:
New
Price: $3,100.00
Description: Actuator Included
Airflow to support 800HP
Up to 650 RWHP with stock emissions equipment and basic supporting mods
Tested in competition setups with extensive supporting mods to make 800+ RWHP
Item #: DM1MO1070303010
Condition:
New
Price: $3,975.00
Description: Does not include Actuator
Airflow to support 800HP
Up to 650 RWHP with stock emissions equipment and basic supporting mods
Tested in competition setups with extensive supporting mods to make 800+ RWHP
Item #: DM1MO1070303000
Condition:
New
Price: $3,500.00
Description: -Actuator Included
-Proven to support up to 625 RWHP with stock emissions
-Extra airflow to make 80-100rwhp over 'Tune only' L5P
-Works great with box tuners, custom tuning, or without tuning...More Details »
Item #: DM1MO1070103010
Condition:
New
Price: $2,650.00
Description: -Actuator Not Included
-Proven to support up to 625 RWHP with stock emissions
-Extra airflow to make 80-100rwhp over 'Tune only' L5P
-Works great with box tuners, custom tuning, or without...More Details »
Item #: DM1MO1070103000
Condition:
New
Price: $1,950.00
Price: $69.00
Exhaust Tail Pipe Tip
Description: Tip 6in OD 5in Inlet 15.5in Length 30° Bend Black-Coated Stainless Steel. Note: Cutting May Be Required for Installation.
Item #: T5154BLK
Condition:
New
Price: $179.11
Sale: $144.99
Save: 19%
Save: $34.12
Exhaust Tail Pipe Tip
Description: Tip 6in OD 5in Inlet 15.5in Length 30° Bend T304 Stainless Steel. Note: Cutting May Be Required for Installation.
Item #: T5154
Condition:
New
Price: $172.93
Sale: $139.99
Save: 19%
Save: $32.94
Engine Coolant Thermostat
Description: Low Temperature Thermostats (set of 2), fits Chevrolet/GMC 6.6L Duramax 2001-2016
Item #: MMTS-CHV-01DL
Condition:
New
Price: $87.95
Engine Coolant Thermostat
Description: High Temperature Thermostats (set of 2), fits Chevrolet/GMC 6.6L Duramax 2001-2016
Item #: MMTS-CHV-01DH
Condition:
New
Price: $85.95
Automatic Transmission Oil Cooler
Description: Transmission Thermal Bypass Valve Kit, fits Chevrolet/GMC 6.6L Duramax L5P 2017+
Item #: MMTC-L5P-TBV
Condition:
New
Price: $128.95
NEW!
Description: Made in America
Uses OEM Connector
Uses OEM Pins
100% Sealed
LIFETIME WARRANTY
Item #: USCAN2D
Condition:
New
Price: $179.99
Electronic Throttle Controller
Description: Pedal Commander throttle response controller with Bluetooth support. You can adjust your gas pedal sensitivity with 36 different modes. It will help your GMC Sierra 3500 HD to accelerate faster!
Item #: PC77
Condition:
New
Price: $299.99
Engine Oil Pan
Item #: 114052201
Condition:
New
Price: $17.99
Steering Tie Rod
Item #: 158030211
Condition:
New
Price: $67.49
Description: Fits 2020-2024 GM 2500/3500 w/ Overload Springs
~6400LBS Load Leveling Capacity at 150PSI
Confirmed 5th Wheel Hitch Compatibility:
OEM Puck System
GNRK1020
For use with factory overload...More Details »
Item #: 88-33200
Condition:
New
Price: $849.95
Suspension Lift Kit
Description: Big Lift Kit w/Shocks 6 in. Lift w/Falcon 1.1 Monotube Shock w/o Factory Air
Item #: 44-19601
Condition:
New
Price: $2,349.95
Suspension Lift Kit
Description: Big Lift Kit w/Shocks 6 in. Lift w/Falcon 1.1 Shocks
Item #: 44-30620
Condition:
New
Price: $2,699.95
Suspension Lift Kit
Description: Big Lift Kit w/Shocks 6 in. Lift w/Rear Falcon 1.1 Monotube Shocks
Item #: 44-39600
Condition:
New
Price: $2,449.95
Suspension Lift Kit
Description: Big Lift Kit w/Shocks 6 in. Lift w/SST3000 Shocks
Item #: 44-30601
Condition:
New
Price: $2,399.95
Suspension Lift Kit
Description: Big Lift Kit w/Shocks 8 in. Lift w/Falcon 1.1 Shocks
Item #: 44-30820
Condition:
New
Price: $2,899.95
Suspension Lift Kit
Description: Big Lift Kit w/Shocks 8 in. Lift w/SST3000 Shocks
Item #: 44-30801
Condition:
New
Price: $2,599.95
Suspension Lift Kit
Description: Big Lift Kit w/Shocks 8 in. Lift w/Upper Control Arms Rear Falcon 1.1 Monotube Shocks
Item #: 44-39800
Condition:
New
Price: $2,849.95
Leaf Helper Spring
Description: Block And Add-A-Leaf Kit 4 in. Blocks Incl. U-Bolts Fits: 2011-15 SILVERADO/SIERRA 2500HD/3500HD-4in. Block kit and U-Bolt
Item #: 26-3204
Condition:
New
Price: $179.95
Leaf Helper Spring
Description: Block And Add-A-Leaf Kit 5 in. Blocks Incl. U-Bolts Fits: 2011-16 SILVERADO/SIERRA 2500HD/3500HD-5in. Block kit and U-Bolt
Item #: 26-3205
Condition:
New
Price: $189.95
Suspension Control Arm
Description: Control Arm Fabricated Upper
Item #: 44-3035
Condition:
New
Price: $499.95
Suspension Leaf Spring Block Kit
Description: Rear Block Kit 1 in. Cast Iron Blocks Incl. Integrated Locating Pin E-Coated U-Bolts Fits: 2011-16 GM/CHEVY HD 2500 2WD/4WD-1.0in. TALL OEM STYLE REAR BLOCK KIT. . CAST CONSTRUCTION WITH PRE CUT...More Details »
Item #: 66-3111
Condition:
New
Price: $149.95
Suspension Leaf Spring Block Kit
Description: Rear Block Kit 1 in. Cast Iron Blocks Incl. Integrated Locating Pin E-Coated U-Bolts Nuts/Washers For Use w/Factory Top Overloads Fits: 2011-16 GM/CHEVY HD 2500 2WD/4WD-1.0in. TALL OEM STYLE...More Details »
Item #: 66-3121
Condition:
New
Price: $149.95
Suspension Leaf Spring Block Kit
Description: Rear Block Kit 2 in. Cast Iron Blocks Incl. Integrated Locating Pin E-Coated U-Bolts Nuts/Washers Fits: 2011-16 GM/CHEVY HD 2500 2WD/4WD-2.0in. TALL OEM STYLE REAR BLOCK KIT. . CAST CONSTRUCTION...More Details »
Item #: 66-3112
Condition:
New
Price: $159.95
Suspension Leaf Spring Block Kit
Description: Rear Block Kit 2 in. Cast Iron Blocks Incl. Integrated Locating Pin E-Coated U-Bolts Nuts/Washers For Use w/Factory Top Overloads Fits: 2011-16 GM/CHEVY HD 2500 2WD/4WD-2.0in. TALL OEM STYLE...More Details »
Item #: 66-3122
Condition:
New
Price: $159.95
Suspension Lift Kit
Description: SST® Lift Kit 3.0 in. Front 2.0 in. Rear
Item #: 69-3030
Condition:
New
Price: $449.95
Suspension Lift Kit
Description: SST® Lift Kit w/Shocks 3.5 in. Front Key Way 2 in. Rear Block Fabricated A-Arm w/ Falcon 1.1 Monotube Shocks
Item #: 69-30350
Condition:
New
Price: $1,499.95
Suspension Lift Kit
Description: SST® Lift Kit w/Shocks 3.5 in. Front/3.0 in. Rear Lift w/Fabricated Control Arms And Bilstein Shocks
Item #: 69-3035
Condition:
New
Price: $1,399.95
Cold Air Intake
Item #: 75-5136
Condition:
New
Price: $349.00
Cold Air Intake
Item #: 75-5136D
Condition:
New
Price: $349.00
Fuel Tank
Description: The distance to empty (DTE) on GM trucks can’t be reprogrammed, so it will show about half the mileage that is really left. This occurs with all aftermarket high-capacity fuel tanks.
The fuel...More Details »
Item #: 10-1016-1
Condition:
New
Price: $1,349.00
Fuel Tank
Description: Important Note about the Fuel Gauge Operation:
The distance to empty (DTE) on GM trucks can’t be reprogrammed, so it will show about half the mileage that is really left. You can multiple the...More Details »
Item #: 10-1017
Condition:
New
Price: $1,249.00
Description: For modified trucks only.
Item #: L5P-CP3-10
Condition:
New
This item will dropship from S&S directly. Rough lead time is 5 Business Days.
This product cannot ship to California.
Price: $2,912.00
Description: For modified trucks only.
Item #: L5P-CP3-12
Condition:
New
This item will dropship from S&S directly. Rough lead time is 5 Business Days.
This product cannot ship to California.
Price: $3,406.00
Description: For modified trucks only.
Item #: L5P-CP3-14
Condition:
New
This item will dropship from S&S directly. Rough lead time is 5 Business Days.
This product cannot ship to California.
Price: $3,900.00
Description: *NO CORE CHARGE*
Item #: L5P-100-SAC
Condition:
New
This item will dropship from S&S directly. Rough lead time is 5 Business Days.
This product cannot ship to California.
Price: $4,305.60
Description: *NO CORE CHARGE*
Item #: L5P-150-SAC
Condition:
New
This item will dropship from S&S directly. Rough lead time is 5 Business Days.
This product cannot ship to California.
Price: $4,903.60
Description: *NO CORE CHARGE*
Item #: L5P-200-SAC
Condition:
New
This item will dropship from S&S directly. Rough lead time is 5 Business Days.
This product cannot ship to California.
Price: $5,501.60
Description: *NO CORE CHARGE*
Item #: L5P-050-SAC
Condition:
New
This item will dropship from S&S directly. Rough lead time is 5 Business Days.
This product cannot ship to California.
Price: $3,707.60
Description: OPEN BOX! 2 of the injectors have a broken connector side guide from the bubble wrap (shown in product photo). This does not affect the connector at all and will still click/lock in.
No Returns.
Item #: L5P-050-SAC - Open Box
Condition:
New
Limited Supply: Only 0 Left!
This product cannot ship to California.
Price: $3,707.60
Sale: $3,000.00
Save: 19%
Save: $707.60
Fuel Tank
Description: Extra Large Midship Tank 56 Gallon
Item #: 7010220
Condition:
New
Price: $1,300.55
Fuel Tank
Description: Extra Large Midship Tank 60 Gallon
Item #: 7010320
Condition:
New
Price: $1,367.05
Description: Brand New - No Core Charge
Item #: ZSG7675
Condition:
New
Price: $509.99
Description: Replaces failure prone plastic factory GM Heater Core Firewall Coolant Fitting
Billet direct-fit replacement with 5/8" barb connection
More resistant to heat and vibration
Double O-ring...More Details »
Item #: WCF100155
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $41.00
Sale: $39.77
Save: 3%
Save: $1.23
Description: - CNC Machined Billet Cap is a direct OEM Replacement not a cover
- Includes new diaphragm seal
- Made in USA
- Black Anodized Finish
- Installs in seconds
Item #: WCF100216
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $44.00
Sale: $42.68
Save: 3%
Save: $1.32
Description: - CNC Machined Billet Cap is a direct OEM Replacement not a cover
- Includes new diaphragm seal
- Made in USA
- Clear Anodized Finish
- Installs in seconds
Item #: WCF100215
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $44.00
Sale: $42.68
Save: 3%
Save: $1.32
Description: #NAME?
Item #: WCF206-19
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $49.00
Sale: $47.53
Save: 3%
Save: $1.47
Description: -CNC Machined Billet Aluminum GM factory oil cap filler neck replacement
-Matches WCFab Billet Aluminum Coolant Tank and Brake Reservoir Caps
-Includes o-ring seal
-Machined cam lock
-Black...More Details »
Item #: WCF100443
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $51.00
Sale: $49.47
Save: 3%
Save: $1.53
Description: -CNC Machined Billet Aluminum GM factory oil cap filler neck replacement
-Matches WCFab Billet Aluminum Coolant Tank and Brake Reservoir Caps
-Includes o-ring seal
-Machined cam lock
-Clear...More Details »
Item #: WCF100442
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $51.00
Sale: $49.47
Save: 3%
Save: $1.53
Description: This aluminum panel cleanly finishes the bottom opening of your 2011-2014 Chevy Silverado HD truck bumper when the lower plastic air dam has been removed.
Allows for installation of more...More Details »
Item #: WCF100368
Condition:
New
Fine Texture Black and Raw in stock and ships in 3-5 business days.10-15 business day lead time on other colors.
Price: $215.00
Sale: $208.55
Save: 3%
Save: $6.45
Description: Fits 2017-2019 Short Bed & Long Bed and 2020-2024 Long Bed (except 2023 & 2024 duallys)
Increase fuel filter capacity and amount of time between filter changes
Anodized billet aluminum fuel...More Details »
Item #: WCF100361
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $245.00
Sale: $237.65
Save: 3%
Save: $7.35