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UnderDog Diesel » 2001, Sierra 2500
Products for:
- Year: 2001
- Model: Sierra 2500
View Universal items for: 2001 Sierra 2500
Browse Products
Item #: LB7-10VCO-R
Condition:
New
This product cannot ship to California.
Price: $1,968.00
Fuel Tank
Description: Extra Large Midship Tank 39 Gallon
Item #: 7010101
Condition:
New
Price: $1,642.55
Fuel Tank
Description: Extra Large Midship Tank 52 Gallon
Item #: 7010201
Condition:
New
Price: $1,642.55
Fuel Tank
Description: Extra Large Midship Tank 62 Gallon
Item #: 7010301
Condition:
New
Price: $1,851.55
Fuel Pump Gasket
Description: Fuel Pump Seal Kit
Item #: 0199003
Condition:
New
Price: $141.55
Fuel Tank Attaching Hardware
Description: Fuel Tank Adaption Kit Incl. Lock Ring/Bottom Ring And O-Rings
Item #: 0199004
Condition:
New
Price: $94.05
![TITAN Fuel Tanks - TITAN Fuel Tanks Installation Kit For Use w/ PN[4010201] - 0101310](https://underdog-diesel.com/images/T198668154.jpeg)
Fuel Tank Attaching Hardware
Description: Installation Kit For Use w/ PN[4010201] Superseded By PN[02 0131 0000]
Item #: 0101310
Condition:
New
Price: $103.55
Fuel Tank
Description: Spare Tire Auxiliary Fuel System
Item #: 4010201
Condition:
New
Price: $2,041.55
Spare Tire Carrier Mount
Description: Spare Tire Buddy In Bed Tire Mount
Item #: 9901330
Condition:
New
Price: $94.05
Fuel Tank
Description: Travel Trekker Auxiliary Diesel Fuel System In Bed 40 Gallon
Item #: 5410040
Condition:
New
Price: $1,329.05
Fuel Tank
Description: Travel Trekker Auxiliary Diesel Fuel System In Bed 50 Gallon
Item #: 5410050
Condition:
New
Price: $1,357.55
Description: Transmission Removal Required
Item #: ALLISON SK
Condition:
New
Price: $225.14
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: - Fully TIG Welded 11 GA Stainless Steel Construction
- Heavy Duty 2" Driver Side Up Pipe
- Heavy Duty 2" Passenger Side Up Pipe
- Up Pipe Gaskets (4)
- Made in USA
Item #: WCF100590
Condition:
New
In Stock. Ships in 3-5 business days.
This Product cannot ship to the state of California
Price: $625.00
Sale: $606.25
Save: 3%
Save: $18.75
Description: Passenger Side Up Pipe
Driver Side Up Pipe
Up Pipe Gaskets (4)
Item #: WCF100589
Condition:
New
10-15 Business Day Lead Time
This product cannot ship to California.
Price: $625.00
Sale: $606.25
Save: 3%
Save: $18.75
Description: ***NOT COMPATIBLE WITH OEM INTAKE***
- Flows 40% Better than Stock
- True 4" Inlet Turbo Intake with smooth flowing transition to turbo compressor cover for optimized airflow and drivability...More Details »
Item #: WCF100535
Condition:
New
10-15 Business Day Lead Time
This product cannot ship to California.
Price: $179.00
Sale: $173.63
Save: 3%
Save: $5.37
Description: - 4" Intake Pipe
- 14g Aluminum Construction
- Air Box & Lid Constructed of 10G Aluminum Sheet
- Dry Air Filter
- Outerwear's Pre-Filter Cover
- Includes Installation Hardware
- 3 1/2" Intake...More Details »
Item #: WCF100300
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 the state of California
Price: $619.00
Sale: $600.43
Save: 3%
Save: $18.57
Description: 3" Driver Side Intercooler Pipe
14g Mandrel Bent Aluminum Construction
Silicone Boots
T-Bolt Clamps
Powder Coating
No tuning required
Item #: WCF100349
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: $305.00
Sale: $295.85
Save: 3%
Save: $9.15
Description: -4" Intake
-Dry Air Filter
-Outerwear's Pre-Filter Cover
-T4 Pedestal with Hardware
-Stainless Steel Oil Feed and Drain Lines with Fittings
-3" Fabricated High Flow Y-Bridge
-3" Hot...More Details »
Item #: WCF100478
Condition:
New
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 the state of California
Price: $2,599.00
Sale: $2,521.03
Save: 3%
Save: $77.97
Description: 5" Intake
Dry Air Filter
Outerwear's Pre-Filter Cover
T4 Pedestal & Spacer with Hardware
Stainless Steel Oil Feed and Drain Lines with Fittings
3" Fabricated High Flow Y-Bridge
3" Hot...More Details »
Item #: WCF100489
Condition:
New
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: $2,789.00
Sale: $2,705.33
Save: 3%
Save: $83.67
Description: - 5" Intake
- Dry Air Filter
- Outerwears Pre-Filter cover
- 3.5" Cold Side Charge Pipe
- 3.5" Turbo Inlet Horn
- 3" One Piece Y-bridge with HD Bead roll end
- 3" Cold Side Intercooler Pipe...More Details »
Item #: WCF100570
Condition:
New
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 the state of California
Price: $3,349.00
Sale: $3,248.53
Save: 3%
Save: $100.47
Description: - 3" Fabricated Y-Bridge (for OEM style intake horn)
- 3" Passenger (Cold) Side Intercooler Pipe
- 3" Driver (Hot) Side Intercooler Pipe
- 14 ga Aluminum Construction
- FPRV Block Off Kit
-...More Details »
Item #: WCF100411
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 the state of California
Price: $1,145.00
Sale: $1,110.65
Save: 3%
Save: $34.35
Description: - 3" Fabricated Y-Bridge (for OEM style intake horn)
- 3" Passenger (Cold) Side Intercooler Pipe
- 3" Driver (Hot) Side Intercooler Pipe
- 4" Intake Pipe
- Air Box with Lid
- Dry Air...More Details »
Item #: WCF100435
Condition:
New
WCFab Red in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
This Product cannot ship to the state of California
Price: $1,799.00
Sale: $1,745.03
Save: 3%
Save: $53.97
Description: 3" Fabricated Billet Y-Bridge
3" Passenger (Cold) Side Intercooler Pipe
3" Driver (Hot) Side Intercooler Pipe
4" Intake Pipe
14g Aluminum Construction
Air Box with Lid
Dry Air Filter...More Details »
Item #: WCF100712
Condition:
New
Ships in 10-15 business days
This product cannot ship to California.
Price: $2,025.00
Sale: $1,964.25
Save: 3%
Save: $60.75
Description: - Fully TIG Welded 11 GA Stainless Steel Construction
- Heavy Duty 2" Passenger Side Up Pipe (Clearanced for conventional down pipes)
- Includes Up Pipe Gaskets (2)
- Made in USA
Item #: WCF100654
Condition:
New
In Stock. Ships in 3-5 business days.
This Product cannot ship to the state of California
Price: $335.00
Sale: $324.95
Save: 3%
Save: $10.05
Description: - Fully TIG Welded 11 GA Stainless Steel Construction
- Heavy Duty 2" Passenger Side Up Pipe Passenger Side Up Pipe for Compound / Twin Turbo Applications
- Full flow design eliminates clearance...More Details »
Item #: WCF100648
Condition:
New
Built to order. 10-15 business day lead time.
This Product cannot ship to the state of California
Price: $335.00
Sale: $324.95
Save: 3%
Save: $10.05
Description: 4" Intake Pipe
14g Aluminum Construction
Air Box & Lid Constructed of 10G Aluminum Sheet
Dry Air Filter
Outerwear's Pre-Filter Cover
Includes Installation Hardware
Silicone Boot &...More Details »
Item #: WCF100190
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: $525.00
Sale: $509.25
Save: 3%
Save: $15.75
Wehrli Custom Fabrication 2001-2004 LB7 Duramax Fuel Pressure Relief Valve Block Off Kit - WCF100023
Description: -Stainless Block off Plug
-5/16" Fuel Line
-5/16" Brass Tee Fitting
-Hose Clamps
Item #: WCF100023
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $72.00
Sale: $69.84
Save: 3%
Save: $2.16
Item #: WCF100797
Condition:
New
In Stock. Ships in 3-5 business days. While Supplies Last!
Price: $250.00
Sale: $242.50
Save: 3%
Save: $7.50
Description: 3" Fabricated Billet Y-Bridge (clearanced for OEM style intake horn)
3" Passenger Side Intercooler Pipe - 14g Mandrel Bent Aluminum Construction
FPRV Block Off Kit
Silicone Boots
T-Bolt...More Details »
Item #: WCF100693
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: $895.00
Sale: $868.15
Save: 3%
Save: $26.85
Description: 3" Downpipe
Heat Wrap
High Temp Ceramic Coating
Bolt on upgrade
No tuning required
Item #: WCF100119
Condition:
New
In Stock. Ships in 3-5 business days.
This product cannot ship to California.
Price: $239.00
Sale: $231.83
Save: 3%
Save: $7.17
Description: 14g Aluminum Coolant Pipe
Silicone Boots
Stainless Steel T-Bolt Clamps
Custom Powder Coat Finish
Item #: WCF100860
Condition:
New
WCFab Red in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
Price: $143.00
Sale: $138.71
Save: 3%
Save: $4.29
Description: - CNC Machined Billet Aluminum Thermostat Upper Housing
- Coolant Pipe
- Silicone Boots
- T-Bolt Clamps
Item #: WCF100405
Condition:
New
WCFab Red, WCFab Grey, Gloss Black, and Gloss White in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
Price: $474.00
Sale: $459.78
Save: 3%
Save: $14.22
Description: Coolant Tank
Low Coolant Level Sensor
Billet Anodized Cap
Over Flow Hose
Coolant Level Sight Glass
Installation Hardware
Powder Coating
Item #: WCF100645
Condition:
New
WCFab Red 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: $473.00
Sale: $458.81
Save: 3%
Save: $14.19
Description: -Coolant Tank
-Low coolant sensor
-Cap
-Hoses
-Clamps
-Fittings
-Powder Coating
Item #: WCF100642
Condition:
New
10-15 Business Day Lead Time
Price: $365.00
Sale: $354.05
Save: 3%
Save: $10.95
Description: Fabricated tubular steel support connects rear housing of Allison transmission to transfer case reinforcing the weaker tail housing section to eliminate flex caused by driveline vibrations which...More Details »
Item #: WCF100130
Condition:
New
WCFab Red & Gloss Black 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: #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: ***For Regular Cab Long Bed, Extended 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 #: WCF100850
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 Extended 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 #: WCF100852
Condition:
New
WCFab Red 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: $989.00
Sale: $959.33
Save: 3%
Save: $29.67
Wehrli Custom Fabrication 2001-2010 Duramax Traction Bar Brackets & Hardware Install Kit - WCF100840
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 side brackets
Item #: WCF100840
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 shield 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 #: WCF100463
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: -Left & Right Mount
-High Grade Hardware for Mount to Engine
-Thread-locker compound
-Poly Bushings
-Powder Coating
Item #: WCF100158
Condition:
New
Gloss black in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
Price: $479.00
Sale: $464.63
Save: 3%
Save: $14.37
Description: - Made from cast A356.0-T6 aluminum
- Includes fasteners, pan, NPT plug, and billet stainless steel Neodymium magnet drain plug
- Finished in your choice of custom powder colors
- Provides 1...More Details »
Item #: WCF100131
Condition:
New
10-15 Business Day Lead Time
Price: $379.00
Sale: $367.63
Save: 3%
Save: $11.37
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 and manifold to up pipe...More Details »
Item #: WCF100363
Condition:
New
In Stock. Ships in 3-5 business days.
This product cannot ship to California.
Price: $1,399.00
Sale: $1,357.03
Save: 3%
Save: $41.97
Description: ARP Up Pipe Bolt kit for 2001-2016 Duramax. 6 Washers and Bolts for installing 1 up pipe. Includes ARP Lube.
Purchase two sets when installing a pair of up pipes.
Item #: WCF100240
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $37.00
Sale: $35.89
Save: 3%
Save: $1.11
Description: Driver Side 2" Stainless Up Pipe
Up Pipe Gaskets (2)
Item #: WCF100652
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: - Up pipe to Turbo gasket
- Up pipe to Manifold gasket
Item #: WCF100364
Condition:
New
Price: $19.95
Sale: $19.35
Save: 3%
Save: $0.60
Description: TIG Welded Fabricated Aluminum Cover for Plastic Reservoir
Utilizes OEM Mounting Points and Hardware
Installs in minutes with basic hand tools
Custom Powder Coat Finish
Item #: WCF100205
Condition:
New
WCFab Red, Bengal Blue, Bengal Red, Gloss Black, and Gloss White in stock and ships in 3-5 business days. 10-15 business day lead time on other colors.
Price: $145.00
Sale: $140.65
Save: 3%
Save: $4.35
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: #NAME?
Item #: WCF100828
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $114.00
Sale: $110.58
Save: 3%
Save: $3.42
Description: -Billet Front Engine Cover
-Stainless Hardware
-CP3 pump mounting plates (or block off plates)
Item #: WCF100127
Condition:
New
Variable lead time. Please call for current availability.
This Product cannot ship to the state of California
Price: $2,995.00
Sale: $2,905.15
Save: 3%
Save: $89.85
Description: -Left and Right side Billet Runner Intakes
-Stainless Hardware
-Stainless Braided pressure crossover line
Item #: WCF100348
Condition:
New
Please call for availability.
This Product cannot ship to the state of California
Price: $2,695.00
Sale: $2,614.15
Save: 3%
Save: $80.85
Description: Aluminum Fabricated Cover
Stainless Hardware
Fill Plug
Custom Powder Coat Finish
Made in USA
Item #: WCF100113
Condition:
New
WCFab 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: $374.00
Sale: $362.78
Save: 3%
Save: $11.22
Description: Mount Bracket
Grade 8 Hardware
Zinc primer & Semi gloss black powder coat finish
Item #: WCF100265
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $99.00
Sale: $96.03
Save: 3%
Save: $2.97
Description: - Left & Right Side L5P Swap Mounts
- Laser Cut, CNC Bent, Welded Steel Construction
- High Grade Hardware Included
- Poly Bushings
- Semi-Gloss Black Powder Coat Finish
- Positions L5P...More Details »
Item #: WCF100170
Condition:
New
In Stock. Ships in 3-5 business days.
Price: $595.00
Sale: $577.15
Save: 3%
Save: $17.85
Description: -3" Down Pipe (HX40 STYLE FLANGE)
-V-band Clamp
-Heat Wrap & Clamps
-High Temp Coating
Item #: WCF100123
Condition:
New
Built to order. 10-15 business day lead time.
This Product cannot ship to the state of California
Price: $249.00
Sale: $241.53
Save: 3%
Save: $7.47
Description: - For installation of fixed vane (Non Coolant Fed) Turbocharger on LB7, LLY, LBZ, LMM Duramax
- Allows removal of the thermostat inside of the upper coolant pipe that feeds coolant to the factory...More Details »
Item #: WCF205-280
Condition:
New
In Stock. Ships in 3-5 business days.
This Product cannot ship to the state of California
Price: $41.00
Sale: $39.77
Save: 3%
Save: $1.23