Tier One +1000HP Competition 48RE Transmission TODT1-48-C-03-X | 2003 5.9L Cummins

Build your 2003 Dodge Ram 2500 or 3500 5.9L Cummins for serious competition with the Tier One Competition 48RE Built Transmission. Engineered for drag racing, dyno competitions, and extreme horsepower applications, this fully built transmission features extensive billet upgrades, increased clutch capacity, and reinforced internal components designed to withstand demanding performance conditions.

Rated by Tier One to handle over 1,000 horsepower, the Competition 48RE is designed for heavily modified Cummins engines equipped with large turbocharger systems, upgraded fuel injectors, and other high-performance modifications. The transmission replaces common factory weak points with high-strength components to provide increased power-holding capability and durability.

At the center of the build is a SunCoast 35-Spline Billet Triple-Disc Torque Converter paired with an oversized 35-spline billet input shaft and TCS billet intermediate shaft. A billet 23-spline output shaft comes standard, with an optional 29-spline output shaft available for additional strength.

The transmission also features a high-pressure race valve body, upgraded billet second-gear band components, TIG-welded ring gears, PTFE-coated thrust washers, and a reinforced three-bolt sprag. Increased clutch capacity includes seven direct clutches, six overdrive clutches, and five forward clutches to provide additional holding power under extreme loads.

Each transmission is fully disassembled, cleaned, inspected, and rebuilt with upgraded internal components, new electronics, seals, gaskets, and a performance rebuild kit. The valve body and completed transmission undergo air-pressure testing and inspection before shipping.

Important: This is a competition-focused transmission designed for extremely firm, quick shifts. It is not intended to provide factory-like shift comfort.

Features

• Over 1,000 HP Capability – Manufacturer-rated for extreme horsepower competition applications
• Complete Competition Transmission – Fully built replacement assembly for compatible 2003 Ram 5.9L Cummins trucks
• SunCoast Billet Triple-Disc Torque Converter – 35-spline design engineered for increased torque capacity
• Oversized 35-Spline Billet Input Shaft – Provides additional strength over factory components
• TCS Billet Intermediate Shaft – Upgraded shaft construction for high-load applications
• Billet Output Shaft – Includes a 23-spline billet output with an optional 29-spline configuration
• High-Pressure Race Valve Body – Designed for increased line pressure and quick, firm shifting
• Optional Fully Manual Valve Body – Available for applications requiring manual shift control
• Billet Second-Gear Band Components – Includes upgraded band, strut, anchor, servo, and 4.2 lever
• Increased Clutch Capacity – Features seven direct, six overdrive, and five forward clutches
• Billet Internal Components – Includes upgraded pistons, clutch drum, clutch retainer, accumulator, and Belleville spring
• TIG-Welded Ring Gears – Reinforced geartrain with optional rollerized planetary gears
• PTFE-Coated Thrust Washers – Designed to improve durability under high loads
• Upgraded Three-Bolt Sprag – Provides increased durability compared to the factory design
• Deep Transmission Pan – Increased fluid capacity supports additional transmission cooling
• New OEM Electronics – Included during the rebuild process
• 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
• Oversized 35-Spline Billet Input Shaft
• TCS Billet Intermediate Shaft
• 23-Spline Billet Output Shaft (Optional 29-Spline)
• High-Pressure Race Valve Body (Optional Fully Manual 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 Forward Piston
• Billet Direct Drum and Piston
• Billet Forward Clutch Retainer
• Upgraded Three-Bolt Sprag
• TIG-Welded Ring Gears
• PTFE-Coated Thrust Washers
• 7 Direct Clutches with Custom Plate
• 6 Overdrive Clutches with Custom Plate
• 5 Forward Clutches
• Machined Transmission Pump Stator
• New OEM Electronics
• Deep Transmission Pan
• Performance Rebuild Kit with New Clutches, Seals, Gaskets, and Sealing Rings

Specifications

• Transmission Model: Chrysler 48RE
• Transmission Type: 4-Speed Automatic
• Build Level: Competition
• Power Rating: Over 1,000 HP
• Torque Converter: SunCoast 35-Spline Billet Triple-Disc
• Input Shaft: Oversized 35-Spline Billet Steel
• Intermediate Shaft: TCS Billet Steel
• Output Shaft: 23-Spline Billet Steel (Optional 29-Spline)
• Valve Body: High-Pressure Race (Optional Fully Manual)
• Direct Clutches: 7
• Overdrive Clutches: 6
• Forward Clutches: 5
• Geartrain: TIG-Welded OEM Gears (Optional Rollerized Planetaries)
• Second-Gear Band: Billet Steel
• Band Lever: Billet Steel 4.2
• Accumulator: Billet Aluminum
• Pistons: Billet Forward and Direct
• Clutch Drum: Billet Steel
• Clutch Retainer: Billet Steel
• Sprag: Upgraded Three-Bolt
• Thrust Washers: PTFE Coated
• Transmission Pan: Deep Pan with Increased Capacity
• Shift Characteristics: Extremely Firm, Competition-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 transmission.
• Competition Shift Characteristics: This transmission produces extremely firm, quick shifts. Aftermarket traction bars may help reduce the effects of harsh shifting.
• Billet Flexplate Recommended: Tier One strongly recommends upgrading to a billet flexplate if the vehicle is not already equipped with one.
• Optional 29-Spline Output Shaft: Four-wheel-drive applications require a custom 29-spline transfer case input. Rear-wheel-drive applications require a custom driveshaft.
• Additional Driveline Upgrades: Tier One recommends the SunCoast 618 Stubby Kit, heavy-duty U-joints, and upgraded slip yokes for applicable 29-spline output configurations.
• 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