Tier One's Stage 1 Allison 1000 Features:
- Built Allison 1000 transmission that can handle heavy towing, tough off-roading, and mild Duramax tuning
- Handles up to 725 horsepower from mild to moderate Duramax tuning and bolt-on parts
- Complete, drop-in transmission for 2011-2016 GM 2500 & 3500 6.6L Duramax LML trucks
- Includes a billet triple-disc torque converter, high-pressure valve body, RatioTek valve body kit, performance overhaul kit with performance clutches, deep transmission pan, new PCS solenoids, new switch manifold, new internal wiring harness, billet PTO cover with C3 oiler upgrade, and new filter
- Fixes common Allison 1000 issues while allowing you to add on more horsepower and torque
- Perfect for heavy towing, off-road rigs with big tires, moderate Duramax tunes for sled pulls, and light drag racing
- Black finish for a great look under your truck
- Valve bodies are both leak-checked and dyno-tested prior to install
- Comes backed by a 2-year, unlimited mileage warranty
- Requires additional core charge and freight shipping
- If you have questions or want a custom Allison 1000 build, contact Tier One or call 602-399-5484!
- Shifting will be slightly firmer than stock
Built Allison 1000 Transmission for Duramax Trucks Looking to Tow Heavy, Run Big Tires, or Add Some Extra Power
While the stock Allison 1000 transmissions have a reputation for being stout, when you start to add a good amount of horsepower and torque from aggressive tuning and bolt-on modifications, the factory Allison transmission starts to show some of its weak points. The Tier One Stage 1 Allison 1000 transmission for 2011-2016 Duramax LML trucks is designed to handle extra horsepower and torque, all while allowing you to tow heavy, add big tires, and let your tough Silverado or Sierra HD truck rip around without its transmission letting you down. The Stage 1 Allison 1000 transmission features new external and internal transmission components that can handle more power and more aggressive applications than your stock Allison so that you can take your tough Duramax truck to the next level both on and off the road.
Comes with a billet triple-disc torque converter, high-pressure valve body, RatioTek Allison Valve Body Kit, Performance Overhaul Kit with Improved Clutches, Transmission Pan with Increased Capacity, new PCS Solenoids, New Switch Manifolds, new Internal Wiring Harness, Billet PTO Cover, and a New Filter
Each Tier One Stage 1 Allison 1000 Transmission gets a suite of both heavy-duty aftermarket upgrades and new OEM components so that the transmission can handle more horsepower and torque while also getting reliable functionality. The Stage 1 Allison Transmission starts out with a billet triple-disc torque converter that's far more resistant to warping and burn-up than the stock converter while also being able to handle far more power. The Stage 1 receives a high-pressure valve body that's also fitted with a RatioTek valve body kit so that the Stage 1 can handle high line pressures while getting firm, but confident shifting throughout all its gears. The Performance Clutch Kit includes all-new C1, C2, C3, and C4 frictions with more durable friction materials than stock to help improve engagement and power-holding when your Duramax is throwing down more power and torque. The Stage 1 Allison transmission comes standard with a deep, cast-aluminum transmission pan that holds more fluid than stock to help keeping temperatures under control. Each transmission also includes new OEM PCS solenoids, new OEM switch new OEM switch manifold, and new filter. The Stage 1 transmission is topped off with a billet PTO cover with "Tier One" lettering and C3 oiler upgrade for improved transmission lubrication. The transmission receives new gaskets and seals before being air-checked for potential leaks.
Fully Overhauled Allison 1000 Transmission for Excellent Reliability
During our build of your Allison Stage 1 transmission, we here at Tier One go over every millimeter of its internal components to guarantee excellent function and reliability. All parts are disassembled and cleaned from our OEM cores to ensure your new Allison 1000 transmission is free from contaminants and other debris. We carefully inspect your transmission’s planetary gear train for damage before fully speccing all bearings and washers for endplay. The valve body is and its solenoids are thoroughly inspected for better than OEM function. The performance rebuild kit includes new clutches, seals, gaskets, and sealing rings to replace all the wearable parts of the transmission before it’s installed on your Silverado or Sierra 2500 or 3500.
Thorough Testing of the Valve Body and Entire Transmission Before Shipping
We here at Tier One take pride in every built Allison 1000 transmission we manufacture for the GM 6.6L LML Duramax trucks. To make sure that you get a transmission that’s as tough as your truck, Tier One puts both the valve bodies and the entire assembled transmission through rigorous testing to ensure you get the reliability you need for heavy towing and hauling applications with your 6.6L Duramax diesel. Before the assembly of the valve body, it goes through vacuum-testing and careful inspection. All valve body solenoids are carefully tested to ensure flawless operation. After assembly of the valve body, it goes through rigorous dyno-testing to ensure proper fluid flow, line pressures, and solenoid operation. After final assembly of the transmission itself, we put it through a complete air-check to find potential leaks.
Specifications:
- Vehicle Fitment: 2011-2016 GM Silverado or Sierra 2500 or 3500 with 6.6L Duramax LML
- Transmission Type: Allison 1000
- Power Rating: up to 725 horsepower
- Torque Converter: Billet triple-disc
- Input Shaft: OEM
- Intermediate Shaft: OEM
- Output Shaft: OEM
- Valve Body: High Pressure
- Valve Body Kit: RatioTek
- Clutch Hub: OEM
- Clutches: SPZ/Raybestos with improved materials
- Transmission Pan: Deep pan with more capacity
- Geartrain: OEM
- PTO Cover: Billet Aluminum with "Tier One" lettering & C3 Oiler Upgrade
For 2011-2016 GM Duramax LML 2500 & 3500 Only: this transmission will only fit 2011-2016 GM 2500 & 3500 6.6L Duramax LML trucks that came with Allison 1000 transmissions from the factory. A
2017-2019 Duramax L5P Stage 1 Allison Transmission and
2008-2010 Duramax LMM Stage 1 Allison Transmission are also available. If you have an older Silverado or Sierra HD, please see all of our
Allison transmissions. If you have a 2011-2016 2500 or 3500 with a 6L90E transmission, please see our
6L90E built transmissions.
Backed by a 2-Year, Unlimited Mileage Warranty: each of our Allison 1000 transmissions comes backed by a 2-year, unlimited mileage warranty. See our
warranty terms and conditions for more details.
Recommended gearing: the following gearing is recommended for the following tire sizes, and is required for Tier One to honor your warranty:
- 35" Tire: 3.73 gears or higher
- 37" Tire: 4.10 gears or higher
- +38" Tire: 4.56 gears or higher
Transmission Break-in: in order to maintain your warranty, this transmission requires a 300-mile break-in and a 100-mile relearn. Please check out
Tier One's Break-In Procedure & Policy here.
Core charge: this transmission includes a $2000.00 core charge that will be refunded upon receipt of your stock transmission. Tier One can also defer your core charge if you create an account our site and save your credit/debit card information. Your card will only be charged if your core is not returned or if there's damage to your core's critical components. For more information on our deferred core charge program, check out our
Deferred Core Terms and Conditions. If you you select "deferred core" from our drop-down, but fail to create an account and save your credit card information, you will be charged a $5.99 deferred core fee. For information on sending in your stock core or any other questions you may have, please give us a call directly at 602-399-5484!
Freight Shipping: this transmission ships via freight. Please carefully inspect your transmission before signing your Bill of Lading. If your transmission arrives damaged, please call us directly at 602-399-5484.