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2003 GMC SIERRA 1500 HD Parts and Accessories
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HP Tuners VCM Suite MPVI4 Credit Pro Packages
HP Tuners Introduces VCM Suite MPVI4 Credit Pro packages, the latest evolution of their industry-leading OBDII interface. Built for professionals and enthusiasts alike, the computer programmers connect your vehicle to VCM Suite software (5.2+) for faster, smarter, and more powerful tuning and diagnostics than ever before. With upgraded hardware, expanded connectivity, and future-ready Wi-Fi capabilities, the MPVI4 redefines what's possible in performance calibration and data acquisition. Models are available with 0, 2, 4, 6, or 8 credits. HP Tuners VCM Suite MPVI4 Credit Pro packages feature: * Improved standalone logging: the most powerful device yet, capable of delivering standalone logging performance on par with VCM scanner and a wired connection * Upgraded hardware architecture: New internal processor for improved data throughput and flashing performance; 30x more memory than previous generation MPVI3 * High-speed USB-C connectivity: Faster, more reliable communication with your PC and vehicle * Bluetooth 5.2: Seamless wireless connection for scanning, logging, and TDN support * Wi-Fi ready (future update): Wireless VCM Suite connectivity coming soon * Enhanced storage and efficiency: Increased onboard memory for robust logging sessions * Improved OBDII fitment: A revised, tapered design means a more secure connection and better compatibility with even more makes/models * Built-In Pro feature set: Standard on every MPVI4, enabling standalone data logging and external sensor integration with PROLINK+ * RGB status LEDs: Clear visual indicators for power, connection, and activity status * Cross-Platform Compatibility: Works with VCM Suite (5.2+), TrackAddict, and RaceRender
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$599.95
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$699.93
On Sale
MSD Blaster OEM Replacement Coils
When it comes to late model performance parts, nothing beats bolt-on and direct connection components—especially when they improve performance like these new replacement MSD Blaster ignition coils. They're designed with improved materials and windings to produce a stronger spark. This improved spark helps burn the fuel mixture more efficiently, resulting in smooth idle and heightened mid-range rpm power. Choose the OEM replacement designed for your year/make/model application.
( 629 )
$562.95
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$727.95
Mishimoto Performance Radiators
Mishimoto performance radiators are designed and engineered to maximize cooling efficiency, boost engine functions, and, most of all, protect your engine from overheating. Many stock radiators can't handle the additional heat that comes higher horsepower levels. So, swap out your stock radiator for an all-aluminum Mishimoto. Key features and benefits of Mishimoto performance radiators include: * Available for universal and exact fit applications (no cutting or modifications required) * All-aluminum construction for optimal heat dissipation, improved strength, and reliability * Increased cooling capacity due to their massive core size * 100 percent brazed aluminum core for minimal distortion, low stress, and clean joints * Available in various sizes with 2-row or 3-row cores * TIG-welded for clean, strong welds and increased durability * Magnetic drain plugs capture metallic debris or fragments * Included high-pressure 1.3 bar cap raises the coolant boiling point for greater safety and efficiency * Automatic transmission and accessory coolers included where applicable
( 321 )
$602.95
Painless Performance Fuel Injection Harnesses
For maximum power with exceptional drivability, transplant the power of fuel injection into your vehicle with Painless Performance fuel injection harnesses. All kits include straightforward instructions and TXL high-temperature, color-coded, and labeled wire for ease of installation. All fuel injection harnesses are 100 percent quality-tested on OmniScanners to ensure the viability of the circuits. Harnesses for both GM and Ford applications are available and they use genuine original equipment connectors for trouble-free installation and operation.
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$659.99
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$725.99
Hedman Street Headers
For the price, no other part can give you the horsepower and fuel economy improvements of Hedman headers. They make Hedman Street headers so well that they guarantee them to be free from defects--including cracks in the tubes and welds--for the life of the headers. Hedman Street headers are available uncoated or in Black Maxx or their polished HTC thermal ceramic coated finishes and, as an added bonus, they also come with all necessary gaskets and mounting hardware. Unless otherwise noted, these headers are designed to fit the vehicle as it came from the manufacturer. This includes components like cylinder heads, chassis, steering, motor mounts, body mounts, and bushings, etc. If your vehicle is using aftermarket components, parts from other applications, or custom-altered parts, then it is the installer's responsibility to verify fitment. Special warning regarding Hedman painted headers only. The paint on these headers is not designed as a final finish; it is designed to protect the headers after the manufacturing process and during shipping. This paint will not withstand the high heat associated with engine break-in, nor will it withstand the heat cycles associated with any type of driving. It is recommended that this protective coating be stripped, and a high heat paint or coating designed for use on headers be applied.
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$548.99
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$734.99
MechMan Elite Series Cast Alternators
MechMan Elite Series cast alternators offer great output at idle RPM and excellent durability in a direct bolt-in package. Their 6-phase technology, combined with massive twin rectifier assemblies and 12 diodes, makes these alternators totally durable for daily use, while still maintaining great output at low-rpm. These alternators will make 180 amps at engine idle speeds—with a full 250 amp output at cruising speeds. The units come with an OEM diameter pulley, making them perfect for high-rpm and racing use. They're available for fitment on a wide range of cars, trucks, and vans from the 1990s and up. Order the model recommended for your application. (Note: Elite Series cast alternators may require a rectangle to oval adapter harness if your vehicle was equipped with the CS144 heavy-duty charging option from the factory. This is not common.)
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$519.00
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$549.00
DeatschWerks Fuel Injectors
DeatschWerks fuels your passion for performance with fuel injectors specifically designed and engineered for your Sport Compact, Modern Muscle, and European vehicles. DeatschWerks fuel injectors are manufactured to fit your OE harness, fuel rail, and manifold. Because they are application-specific, you'll spend less time installing and tuning, so you can spend more time enjoying the increased performance of your ride! They provide an excellent spray pattern and atomization for optimized idle and tuning. Each set is flow-matched both statically and dynamically, and flow-balanced to within one to two percent. A flow report is included with each set of DeatschWerks fuel injectors.
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$599.00
MechMan Elite Series Billet Alternators
MechMan Elite Series billet alternators offer great amperage output and durability. Their 6-phase technology, combined with massive twin rectifier assemblies and 12 diodes, makes these stunning alternators totally durable for daily use. Plus, the 6-phase hairpin stators make the alternators fundamentally more efficient, equating to incredible output at extremely low engine rpm, less energy wasted in the form of heat, and more horsepower to the wheels. MechMan Elite billet models are available for replacement or upgrade, and they are available in a unique selection of finishes and amperage outputs. Choose one designed for your vehicle.
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$629.00
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$699.00
Summit Racing™ Battery Pro Packs
Summit Racing™ battery Pro Packs combo an Optima RedTop battery, Painless battery cable kit, and a tray/hold-down kit for a complete install in your vehicle. The high performance AGM RedTop is Optima's ultimate starting battery designed to deliver a strong burst of ignition power for a reliable start-up every time. The batteries offer longer life, more vibration resistance, no maintenance, and are virtually spill proof and mountable in most any position. Painless Performance battery cable kits include a red 1-gauge positive and a black 1-gauge negative cable with lightweight abrasion-resistant insulation capable of handling over 250 amps and heavy-duty terminals already installed, side post adapters, and high-amp crimp ring terminals. Their 16 ft. length make them ideal for trunk-mounted batteries and custom installs. The battery tray/hold-downs are made from premium aluminum and chosen to match the battery in the Summit Racing™ Pro Pack selected.
Not Yet Reviewed
$540.97
Summit Racing™ Positraction Differential Carriers
Summit Racing™ Positraction differential carriers deliver aggressive, yet smooth, controllable traction. Our carriers feature nodular iron cases, forged steel internals, strong teeth—and they're fully rebuildable. We offer fitments for dozens of axle models. Whether replacing or upgrading, Summit Racing™ Positraction differential carriers will put power to the pavement, providing the confidence and performance you need.
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$641.99
JBA Performance Exhaust Cat4ward Headers
Increase your horsepower and torque with JBA Cat4ward headers! They are designed with 3/8 in. thick laser-cut flanges, mandrel-bent primary tubes, and feature JBA's patented Firecone merge collectors. They're available in either steel or 409 stainless steel and are offered in a chrome plated or high-temperature silver ceramic finish for most applications. JBA includes premium-quality mounting hardware and instructions for the installation and, unless otherwise noted, these headers are designed to fit the vehicle as it came from the manufacturer. This would include components such as cylinder heads, chassis, steering, motor mounts, body mounts, bushings, etc. If aftermarket components, parts from other applications, or custom-altered parts are used on your vehicle, it is the installer's responsibility to verify fitment.
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$694.95
Key Parts Steel Hoods
Key Parts steel hoods are designed and constructed using precision tooling to offer nothing less than a high-standard fit and function. Each style features a black EDP coating for rust protection, strength, and durability—and is extensively tested to ensure quality. Key Parts steel hoods are paintable to match the color of your vehicle; they use factory hardware and fasteners to facilitate an easy install for professional looking results. The hoods are available in dozens of models, including styles such as Cowl induction, Ram Air, and Cobra. Order the replacement needed for your specific application.
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$566.99
DiabloSport Trinity 2 EX Platinum Performance Programmers
DiabloSport Trinity 2 EX Platinum Performance programmers are game-changers! Trinity (T2) EX units are extremely capable performance tuners and feature-packed monitor/data logger devices—offering the best of both worlds. They feature an impressive, high-resolution 5 in. capacitive touchscreen, full swipe functionality, and industry-leading gauge designs; plus, jaw-dropping power potential and a powerful, yet simple user interface. DiabloSport Trinity 2 EX Platinum Performance programmers feature: * Full-color, high-definition 5 in. touchscreen * Lightning fast read/write times * Performance tuning for mileage, towing, daily driving, and performance * One-Touch, easy menu navigation * Full data-logging capability * Read and clear diagnostic trouble codes * Multi-vehicle licenses available * Correct speedometer and adjust speed/rev limiters (Options, features and coverage may vary, based on vehicle application) * AFM/MDS active fuel management options (Options, features and coverage may vary, based on vehicle application)
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$727.95
Standard Motor Fuel Injectors
Standard Motor Products fuel injectors help you attain maximum fuel efficiency and power from your engine. Properly operating injectors are essential components for enabling your vehicle to run flawlessly. These OEM stock replacements are available for hundreds of specific applications. Don't drive with faulty fuel delivery. Update worn or malfunctioning fuel injectors with reliable models from Standard Motor Products.
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$568.99
Motive Gear Ring and Pinion Sets
Motive Gear is the leading manufacturer of driveline products for just about any vehicle, whether it is a stock daily driver or a full-competition 4x4 or race car. They are proud to offer an unmatched selection of quality components engineered and manufactured for the vehicle and for the way it is driven. Motive Gear ring and pinion sets are engineered to meet or exceed OEM specifications at a price that won't break your budget. Their broad selection of ring and pinion ratios is available for just about every vehicle made from the 1940s through the present. All Motive Gear products meet strict quality standards through advanced manufacturing techniques and are backed by their strong warranty. Their in-house quality control lab utilizes state-of-the-art equipment to continuously check Motive Gear products for strength, tolerance, and hardness. Only after meeting stringent quality standards are Motive Gear products packaged and ready for delivery.
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$512.99
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$679.99
BD Diesel Exhaust Manifolds
These BD Diesel exhaust manifolds help you maximize your engines true potential. Your stock manifolds can require extensive cleaning and machining to be recovered from warping and distortion. These heavy-walled manifolds are coated to resist corrosion, with some models even predrilled for pyrometer probes. BD Diesel exhaust manifolds are great preventative upgrades whenever you're doing other engine work.
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$573.95
Fluidyne High Performance Radiators
Fluidyne high performance radiators feature aluminum end tanks and 100 percent NOCOLOK brazed aluminum cores, rather than the epoxy-bonded types used by others. These cores are built using high-efficiency cooling fins that deliver maximum performance and durability. The radiators are offered in universal sizes, as well as exact fit, with all brackets, fittings, and hoses set up to match the original equipment layout for easy installation—and they meet ISO 9001 standards for quality. Fluidyne radiators are available in crossflow and downflow styles, and a range of sizes for vehicle-specific applications; some models also include a transmission cooler. Keep your ride cool on the hottest days or at the track with a Fluidyne radiator.
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$599.00
RoadActive HD Suspension Systems
For vehicles that operate under load, daily or distance, RoadActive HD suspension systems should be considered a necessity. They come fully assembled out of the box and ready for installation. Installing an active suspension to your rear leaf spring suspension will upgrade your truck's load carrying, vehicle stability, and control without compromising your ride. These HD systems add critical strength to your leaf springs—but will not compromise ride quality, with or without a load. The patented design also enhances vehicle performance by controlling sway, body roll, axle wrap, wheel hop, and bottoming out. Once installed, no maintenance or adjustments are ever required. Kits are available for hundreds of vehicles from the 1970s and up.
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$589.00
Flex-A-Lite Direct-Fit Electric Fans
Flex-A-Lite direct-fit fans delivers all of the advantages of an electric cooling fan—quicker warm-ups and cool-downs, additional horsepower and torque, quieter operation, and a custom installation. All necessary mounting hardware is included, making them that much easier to install. Flex-A-Lite direct fit electric fans are available in a variety of sizes, quantities, and cfm abilities. Choose the model that best complements your engine compartment.
( 29 )
$626.99
On Sale
ACCEL Super Coils
ACCEL Super Coils are engineered for a faster rise time and a longer spark duration. They produce higher spark energy for increased performance. These coils are available for a wide variety of specific engine applications. Order the set designed for your make and model.
( 809 )
$579.95
Go Rhino Bed Bars
Rhino bed bars from Go Rhino will add intimidating off-road style to your pickup. Constructed from 3 in. diameter steel tubing, these bed bars stand tough—and they come in a black powdercoat, chrome, or polished stainless finish to trick out any truck. Go Rhino bed bars feature a complete bolt-together design with no exposed welds or mounting hardware and also include hard plastic gaskets to eliminate any metal-to-metal contact. Choose your bed bars in single, double, or triple-bar style to get the right look for your truck. For even more utility, add an optional light bar and lights (sold separately) to your Go Rhino bed bars!
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$739.99
RoadActive Suspension Systems
RoadActive Suspension systems are the only rear leaf spring suspension upgrade that converts basic "passive" leaf spring suspension to mechanical "active" suspension. Their systems absorb and dissipate load force energy, resulting in significantly improved vehicle stability, balance, traction, and control … all with or without a load. RoadActive Suspension systems add critical strength to leaf springs, but will not compromise ride quality. They're like helper springs, sway bars, and traction bars, all in one package. The systems are available for thousands of vehicles from the 1960s and up. Order the kit recommended for your application. Features include: * Improved driver control, safety, and stability, with or without a load * Eliminate sway and reduce roll on corners * Reduce axle wrap and wheel hop * Strengthen rear leaf springs for towing or hauling maximum loads with maximum safety * Absorb loads, rather than resist them, for a much more comfortable ride * Eliminate the need for fitting extra leaves or stiffening the springs * Better handling and control in windy and rough road conditions * Easy to install--can be fitted in approximately 60 minutes with no welding or drilling * Secured under their own coil spring tension
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$539.00
Melling Stock Replacement Cam and Lifter Kits
Restore your engine to its true power potential with Melling's stock replacement cam and lifter kits. They're perfect for either replacement or stock rebuilds. Melling cam and liter kits also include a matched set of lifters so you won't have to worry about mismatched parts during installation.
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$684.99
ACDelco Differential Carriers
Have to replace the differential carrier on your vehicle? ACDelco differential carriers are genuine OEM replacements with the fit of original equipment. Made with top-notch OEM-quality, these units are built to not only last, but keep your vehicle operating safely.
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$554.99
