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UnderDog Diesel » 2020, Sierra 3500
Products for:
- Year: 2020
- Model: Sierra 3500
View Universal items for: 2020 Sierra 3500
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Suspension Leveling Kit
Description: Leveling Kit 2.0 in. Front
Item #: 66-3020
Condition:
New
Price: $229.95
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
Description: -Your Choice of Custom Exergy Sportsman, 10mm, 12mm, or 14mm CP3 pump specific to this kit
-Billet Aluminum, Black Anodized CP3 Pump Mount Plate
-High Pressure Fuel Line
-High Pressure Rail...More Details »
Item #: WCF100455, WCF100456, WCF100457, WCF100458
Condition:
New
In stock. Ships in 3-5 business days.
This Product cannot ship to the state of California
Price: $2,495.00
Sale: $2,420.15
Save: 3%
Save: $74.85
Description: -Mount Bracket
-Zinc primer & Semi gloss black powder coat finish
Item #: WCF100276
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $62.00
Sale: $60.14
Save: 3%
Save: $1.86
Description: - Gasket Kit for 2017-2023 L5P / 2019+ L5D Duramax OEM/VGT Turbos
Item #: WCF100178
Condition:
New
In stock. Ships in 3-5 business days.
Price: $145.00
Sale: $140.65
Save: 3%
Save: $4.35
Description: Passenger Side Up Pipe
Driver Side Up Pipe
Up Pipe Gaskets (4)
Flows 26% Better than OEM
Made in USA
Item #: WCF100624
Condition:
New
In Stock. Ships in 3-5 business days.
This product cannot ship to California.
Price: $689.00
Sale: $668.33
Save: 3%
Save: $20.67
Description: Flows 27% Better than Stock
True 4" Inlet Turbo Intake with smooth flowing transition to strategically designed anti-surge face which properly engages into turbo compressor cover for optimized...More Details »
Item #: WCF100775
Condition:
New
WCFab Red and WCFab Grey in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
Price: $259.00
Sale: $251.23
Save: 3%
Save: $7.77
Description: CNC Machined Billet Aluminum Plug
Black anodized finish with engraved logo
NO Tuning required, bolt on!
Will fit on stock truck no other modifications or upgrades necessary!
Item #: WCF100473
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $31.00
Sale: $30.07
Save: 3%
Save: $0.93
Description: - Fully TIG Welded, CNC machined billet steel exhaust manifolds
- Finished in Black Ceramic Coat rated for 1800ºF
- Includes new gaskets for manifold to cylinder head, EGR flange, and manifold...More Details »
Item #: WCF100226
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $2,159.00
Sale: $2,094.23
Save: 3%
Save: $64.77
Description: Fully TIG Welded, CNC machined billet steel exhaust manifolds
Finished in Black Ceramic Coat rated for 1800ºF
Includes new gaskets for manifold to cylinder head, EGR flange, and manifold...More Details »
Item #: WCF100373
Condition:
New
In Stock. Ships in 3-5 business days.
This product cannot ship to California.
Price: $1,574.00
Sale: $1,526.78
Save: 3%
Save: $47.22
Description: - Direct Replacement for OEM Thermostat Housing
- Custom Powder Coat Finish
- Cleans up engine bay appearance
- Completes the look when also running one of our Upper Coolant Pipes
Item #: WCF100188
Condition:
New
Gloss White, Gloss Black, WCFab Red, and WCFab Grey in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
Price: $179.00
Sale: $173.63
Save: 3%
Save: $5.37
Description: ARP Up Pipe Bolt kit for 2017+ Duramax. 12 Washers and Bolts for installing both up pipes. Includes ARP Lube
Item #: WCF100199
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $60.00
Sale: $58.20
Save: 3%
Save: $1.80
Item #: WCF100822
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $153.00
Sale: $148.41
Save: 3%
Save: $4.59
Description: 3.5" Steel Down Pipe
High Temp Black Ceramic Coat Finish
Heat Wrap Pre-installed
Catalyst Back - Emissions Compliant
NO TUNING REQUIRED!
Made in USA
Item #: WCF100129
Condition:
New
In Stock. Ships in 3-5 business days.
This product cannot ship to California.
Price: $335.00
Sale: $324.95
Save: 3%
Save: $10.05
Description: ***For Regular Cab Long Bed, Double Cab Short Bed and Crew Cab Short Bed Models***
-LIFETIME WARRANTY against bending or breaking (to original purchaser)
-60" Heavy Duty Bars
-Poly Bushings...More Details »
Item #: WCF100826
Condition:
New
WCFab Red with Standard Brushed Tag, Gloss Black with Standard Brushed Tag, and Gloss White with Standard Brushed Tag in stock and ships in 3-5 business days. 10-15
business day lead time on other colors.
Price: $989.00
Sale: $959.33
Save: 3%
Save: $29.67
Description: ***For Double Cab Long Bed and Crew Cab Long Bed Models***
-LIFETIME WARRANTY against bending or breaking (to original purchaser)
-68" Heavy Duty Bars
-Poly Bushings
-RockJock Johnny Joints...More Details »
Item #: WCF100876
Condition:
New
WCFab Red with Standard Brushed Tag, Gloss Black with Standard Brushed Tag, and Gloss White with Standard Brushed Tag in stock and ships in 3-5 business days. 10-15
business day lead time on other colors.
Price: $989.00
Sale: $959.33
Save: 3%
Save: $29.67
Wehrli Custom Fabrication 2020-2024 Duramax Traction Bar Brackets & Hardware Install Kit - WCF100831
Description: Includes Axle side bolt on and Frame side weld on mounts
Grade 8 Hardware
This part number is mounting hardware only - Bars not included
Powder Coating with zinc primer base coat on axle...More Details »
Item #: WCF100831
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $274.00
Sale: $265.78
Save: 3%
Save: $8.22
Description: Replaces OEM plastic front cover for lower engine bay and cooling stack which is prone to cracking and breaking.
Constructed from heavy gauge aluminum
Uses OEM mounting points
Provides...More Details »
Item #: WCF100459
Condition:
New
Fine Texture Black in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
Price: $289.00
Sale: $280.33
Save: 3%
Save: $8.67
Description: Aluminum Fabricated Cover
Stainless Hardware
Fill Plug
Custom Powder Coat Finish
Item #: WCF100114
Condition:
New
WCFab Red and Gloss Black in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
Price: $374.00
Sale: $362.78
Save: 3%
Save: $11.22
Wehrli Custom Fabrication 2020-2024 GM 2500/3500HD Truck 3/4 in. Front Bumper Spacer Kit - WCF100444
Description: WCFab 3/4" Front Bumper Spacer Kit for 2020-2024 GM 2500/3500 HD Trucks improves aftermarket wheel and tire fitment options by moving front bumper forward and away from front wheels creating more...More Details »
Item #: WCF100444
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $199.00
Sale: $193.03
Save: 3%
Save: $5.97
Wehrli Custom Fabrication 2020-2024 GM 2500/3500HD Truck 3/8 in. Front Bumper Spacer Kit - WCF100446
Description: WCFab 3/8" Front Bumper Spacer Kit for 2020-2024 GM 2500/3500 HD Trucks improves aftermarket wheel and tire fitment options by moving front bumper forward and away from front wheels creating more...More Details »
Item #: WCF100446
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $142.00
Sale: $137.74
Save: 3%
Save: $4.26
Description: Qty. 4 CNC Machined Billet Aluminum Marker Light Delete Plates
High quality mounting hardware
Marker Light Harness Dummy Plugs
Available with or without machined WCFab logo in Raw Aluminum...More Details »
Item #: WCF100390, WCF100391, WCF100392, WCF100393
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $249.00
Sale: $241.53
Save: 3%
Save: $7.47
Description: 3.5 in. Cold Side Intercooler Pipe
Incorporated threaded bung to reinstall OEM Intake Temperature Sensor
Durable Powder Coat Finish
Silicone Boot
T-Bolt Clamps
O-Rings
14g Mandrel...More Details »
Item #: WCF100381
Condition:
New
WCFab Red, WCFab Grey, and Gloss Black in stock and ships in 3-5 business days. 10-15 business day lead time on other
colors.
This product cannot ship to California.
Price: $374.00
Sale: $362.78
Save: 3%
Save: $11.22
Description: 4" Intake Pipe
Air Box & Lid Constructed of 10G Aluminum Sheet
Dry Air Filter
Outerwear's Pre-Filter Cover
Hardware
Seal for Connection to Functional Ram Air Port on Hood
High...More Details »
Item #: WCF100702
Condition:
New
This product cannot ship to California.
Price: $629.00
Sale: $610.13
Save: 3%
Save: $18.87
Description: 4" Intake Pipe
3 1/2" Intake Horn
Air Box & Lid Constructed of 10G Aluminum Sheet
Dry Air Filter
Outerwear's Pre-Filter Cover
Hardware
Seal for Connection to Functional Ram Air...More Details »
Item #: WCF100684
Condition:
New
WCFab Red, WCFab Grey, Gloss White, and Gloss Black in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
This product cannot ship to California.
Price: $835.00
Sale: $809.95
Save: 3%
Save: $25.05
Description: 4" Intake Pipe
Silicone Hump and Straight Boots
T-bolt Clamps
Powder coating
NO Tuning required, bolt on!
Will fit on stock truck no other modifications or upgrades necessary! More Details »
Item #: WCF100720
Condition:
New
WCFab Red with Standard Brushed Tag, WCFab Grey with Standard Brushed Tag, and Gloss Black with Standard Brushed Tag in stock and ships in 3-5 business days. 10-15
business day lead time on other colors.
This product cannot ship to California.
Price: $225.00
Sale: $218.25
Save: 3%
Save: $6.75
Description: - Auxiliary Coolant Tank for Fuel Cooler
- Black Anodized Billet Aluminum Cap
- Overflow Flow Fitting
- Preformed Hose
- Custom Powder Coat Finish
Item #: WCF100224
Condition:
New
WCFab Red, Bengal Red, Gloss White, and Gloss Black in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
Price: $239.00
Sale: $231.83
Save: 3%
Save: $7.17
Description: Coolant Tank
Low Coolant Level Sensor
Black Anodized Billet Aluminum Cap
Over Flow Hose
Coolant Level Sight Glass
Installation hardware
Powder Coating More Details »
Item #: WCF100268
Condition:
New
WCFab Red with Standard Brushed Tag, WCFab Grey with Standard Brushed Tag, Gloss White with Standard Brushed Tag, and Gloss Black with Standard Brushed Tag in stock and
ships in 3-5 business days. 10-15
business day lead time on other colors.
Price: $525.00
Sale: $509.25
Save: 3%
Save: $15.75
Description: 3 in. Hot Side Intercooler Pipe
3.5 in. Cold Side Intercooler Pipe
CNC Machined Flange and black anodized billet aluminum adapter with Double O-Rings provides an improved sealing surface to...More Details »
Item #: WCF100410
Condition:
New
WCFab Red, WCFab Grey and Gloss Black in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
This product cannot ship to California.
Price: $679.00
Sale: $658.63
Save: 3%
Save: $20.37
Description: 4 in. Aluminum Intake Pipe
3.5 in. Intake Horn with PCV Port and Surge Ring
Air box enclosure with dry filter assembly and Outerwears pre-filter cover
Installation hardware, 4 in....More Details »
Item #: WCF100414
Condition:
New
WCFab Red, WCFab Grey, Candy Teal, Gloss White, and Gloss Black in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
This product cannot ship to California.
Price: $1,515.00
Sale: $1,469.55
Save: 3%
Save: $45.45
Description: 4 in. Aluminum Intake Pipe
3.5 in. Intake Horn with PCV Port and Surge Ring
Air box enclosure with dry filter assembly and Outerwears pre-filter cover
Installation hardware, 4 in....More Details »
Item #: WCF100418
Condition:
New
WCFab Red, Candy Teal, and Gloss White in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
This product cannot ship to California.
Price: $1,829.00
Sale: $1,774.13
Save: 3%
Save: $54.87