Tier One 1000HP Stage 3 48RE Transmission TODT1-48-ST3-03-X | 2003 Ram 5.9L Cummins 2500 & 3500

Upgrade your 2003 Dodge Ram 2500 or 3500 5.9L Cummins with the Tier One Stage 3 48RE Built Transmission. Engineered for high-horsepower applications, drag racing, sled pulling, and dyno competitions, this fully rebuilt transmission combines high-strength billet components, upgraded clutch capacity, and reinforced internal parts to improve durability and power handling.

Rated by Tier One to support up to 1,000 horsepower, the Stage 3 48RE is designed for heavily modified Cummins trucks equipped with upgraded turbocharger systems, performance fuel injectors, and other high-output modifications. The transmission addresses common factory 48RE weaknesses while providing the strength needed for demanding performance applications.

The Stage 3 features a SunCoast 35-Spline Billet Triple-Disc Torque Converter paired with a Sonnax 35-spline billet input shaft, Sonnax billet intermediate shaft, and billet 23-spline output shaft. These upgraded drivetrain components provide additional strength to handle increased horsepower and torque.

Additional upgrades include a Tier One High-Pressure Race Valve Body, billet second-gear band components, TIG-welded ring gears, PTFE-coated thrust washers, and a billet Belleville spring. The performance rebuild kit includes seven direct clutches and six overdrive clutches to increase holding capacity under heavy loads.

Each transmission is completely disassembled, cleaned, inspected, and rebuilt with upgraded components, new seals, gaskets, and sealing rings. The valve body and completed transmission undergo air-pressure testing and inspection before shipping to help ensure proper operation.

Important: This transmission is designed for performance and competition applications and features firm, quick shifting compared to a factory transmission.

Features

• Up to 1,000 HP Capability – Manufacturer-rated for high-horsepower Cummins performance applications
• Complete Built Transmission – Designed as a replacement assembly for compatible 2003 Ram 5.9L Cummins trucks
• SunCoast Billet Triple-Disc Torque Converter – 35-spline construction designed for increased torque capacity
• Sonnax 35-Spline Billet Input Shaft – Upgraded shaft construction for improved power handling
• Sonnax Billet Intermediate Shaft – Provides additional internal drivetrain strength
• Billet 23-Spline Output Shaft – Designed to withstand demanding high-load applications
• High-Pressure Race Valve Body – Designed for increased line pressure and firm, responsive shifting
• Billet Second-Gear Band Components – Includes upgraded band, strut, anchor, servo, and 4.2 lever
• Billet Accumulator – Provides increased durability compared to the factory component
• TIG-Welded Ring Gears – Reinforced to improve strength under high loads
• PTFE-Coated Thrust Washers – Designed to improve wear resistance and durability
• Billet Belleville Spring – Upgraded for increased strength and reliability
• Increased Clutch Capacity – Includes seven direct clutches and six overdrive clutches
• Heavy-Duty Governor Solenoid & Transducer – Upgraded to address common factory failure points
• Deep Transmission Pan – Increased fluid capacity supports additional transmission cooling
• Performance Rebuild Kit – Includes upgraded BorgWarner clutches, seals, gaskets, and sealing rings
• Thoroughly Inspected and Tested – Valve body and completed transmission undergo air-pressure testing
• Black Exterior Finish – Provides a clean, finished appearance
• 2-Year/Unlimited-Mileage Warranty – Subject to Tier One warranty terms and conditions

Upgraded Components

• SunCoast 35-Spline Billet Triple-Disc Torque Converter
• Sonnax 35-Spline Billet Input Shaft
• Sonnax Billet Intermediate Shaft
• 23-Spline Billet Output Shaft
• Tier One High-Pressure Race Valve Body
• Billet Second-Gear Band
• Billet Second-Gear Band Strut
• Billet Second-Gear Band Anchor
• Billet Second-Gear Servo
• Billet 4.2 Band Lever
• Billet Accumulator
• Billet Belleville Spring
• Billet Rear Servo
• TIG-Welded Ring Gears
• PTFE-Coated Thrust Washers
• 7 Direct Clutches
• 6 Overdrive Clutches
• Heavy-Duty Governor Solenoid
• Heavy-Duty Governor Pressure Transducer
• Machined Transmission Pump Stator
• Deep Transmission Pan
• Performance Rebuild Kit with BorgWarner Clutches, Seals, Gaskets, and Sealing Rings

Specifications

• Transmission Model: Chrysler 48RE
• Transmission Type: 4-Speed Automatic
• Build Level: Stage 3
• Power Rating: Up to 1,000 HP
• Torque Converter: SunCoast 35-Spline Billet Triple-Disc
• Input Shaft: Sonnax 35-Spline Billet Steel
• Intermediate Shaft: Sonnax Billet Steel
• Output Shaft: 23-Spline Billet Steel
• Valve Body: High-Pressure Race
• Clutches: BorgWarner Performance Rebuild Kit
• Direct Clutch Count: 7
• Overdrive Clutch Count: 6
• Geartrain: OEM with Additional TIG Welding
• Second-Gear Band: Billet Steel
• Band Strut: Billet Steel
• Band Anchor: Billet Steel
• Band Lever: Billet Steel 4.2
• Accumulator: Billet Aluminum
• Thrust Washers: PTFE Coated
• Governor Solenoid & Transducer: Heavy-Duty
• Transmission Pan: Deep Pan with Increased Capacity
• Shift Characteristics: Firm, Performance-Oriented
• Warranty: 2 Years / Unlimited Mileage
• Core Charge: $2,500
• Shipping Method: Freight

Vehicle Fitment

• 2003 Dodge Ram 2500 5.9L Cummins with 48RE Transmission
• 2003 Dodge Ram 3500 5.9L Cummins with 48RE Transmission

Required Gear Ratios

Tier One specifies the following axle gear ratios based on tire size to maintain warranty eligibility:

• 35" Tires: 3.73 or Numerically Higher
• 37" Tires: 4.10 or Numerically Higher
• Larger Than 38" Tires: 4.56 or Numerically Higher

Important Application Notes

• 2003 Model Year Only: Designed specifically for 2003 Dodge Ram 2500 and 3500 trucks equipped with the 5.9L Cummins and compatible 48RE automatic transmission.
• Performance Shift Characteristics: This transmission features firm, quick shifting. Aftermarket traction bars may help reduce the effects of harsh shifts.
• Billet Flexplate Recommended: Tier One strongly recommends upgrading to a billet flexplate if the vehicle is not already equipped with one.
• Core Charge: A $2,500 refundable core charge applies. Refund eligibility depends on the condition and acceptance of the returned transmission. Advance core returns may reduce or eliminate the charge.
• Freight Shipping: This transmission ships via freight. Inspect the shipment for damage before signing the Bill of Lading and document any damage with the carrier.
• Warranty Requirements: Tire size, axle gearing, installation procedures, and other manufacturer conditions may affect warranty eligibility.
• Professional Installation Recommended: Installation should be completed by a qualified transmission technician familiar with high-performance 48RE applications.

Fitment: 2003 Dodge Ram 2500 & 3500 5.9L Cummins with 48RE Transmission

Manufacturer: Tier One Transmissions