TREMEC TKX 5-Speed Conversion Kit for MOPAR Street Rod & Truck

Upgrade your vintage MOPAR street rod or classic truck with modern drivetrain performance. The TREMEC TKX 5-Speed Overdrive Kit by Silver Sport Transmissions (SST) delivers modern highway cruising, reduced cabin noise, and massive torque capacity while maintaining your vehicle’s classic look.

Whether you are upgrading from a 3-speed or 4-speed manual, or executing a full automatic-to-manual conversion, this kit replaces weak factory components with a transmission engineered specifically for high-performance street and truck applications.

Why Upgrade to the TREMEC TKX 5-Speed?

The TREMEC TKX is the most compact, high-strength 5-speed manual transmission on the market, blending brute aftermarket strength with smooth street manners.

• High Torque & RPM Capacity: Built to handle up to 600 lb-ft of continuous torque and crisp gear shifts up to 7,500 RPM.
• Compact Case Design: Features a streamlined, rounded case designed to fit tight classic MOPAR transmission tunnels with minimal or no modifications.
• Massive Fuel Economy Gains: Enjoy a 30% to 50% increase in fuel economy and low-RPM highway cruising thanks to the integrated overdrive gear.
• Refined Driving Experience: Drastically reduces NVH (noise, vibration, and harshness) inside the cab.
• Versatile Clutch Setup: Easily switches between mechanical and hydraulic clutch actuators by removing just a few external bolts—no transmission teardown required.

Available TKX Gear Ratios

Tailor your MOPAR's acceleration and cruising RPMs to match your rear differential. We offer wide-ratio and close-ratio configurations:

Basic Kit Components (Manual-to-Manual Conversion)

This core kit contains the fundamental components needed to upgrade your factory 3-speed or 4-speed manual transmission:

• TREMEC TKX 5-Speed Overdrive Transmission: Modified by SST to provide a factory-correct shifter position and featuring an engineered crossmember to maintain perfect driveline angles.
• Super Heavy-Duty Needle Roller Pilot Bearing: Includes a built-in lube seal for maximum service life.
• SST Premium Isolator Mount: High-quality rubber to absorb drivetrain vibrations (heavy-duty polyurethane available for track applications).
• Speedometer Connection: Dual-compatible for both mechanical and electronic speedometers.
• Wiring & Hardware: Includes a waterproof reverse lights connector, matching slip yoke, and fully labeled installation hardware.
• Support & Warranty: Detailed, step-by-step installation instructions backed by an industry-leading warranty and free lifetime technical support.

Note: Driveshafts are no longer bundled automatically but are available for purchase separately.

Optional Upgrades & Automatic-to-Manual Conversions

Building a ground-up project or swapping from an automatic? Complete your build with these premium, tailored add-ons:

• McLeod Flywheel & Clutch Packages: Billet steel flywheels (superior durability over cast steel) and high-performance, low-effort street clutches.
• Performance Bellhousings: Choose from a lightweight titanium-aluminum OEM-style housing or a high-strength steel scatter shield that meets track safety requirements.
• Complete Hydraulic Clutch Kit: Reduces pedal effort using a heavy-duty concentric slave cylinder (1,000,000 cycle service life), a pre-engineered firewall mount to eliminate guesswork, a remote reservoir, and braided stainless steel pressure lines.
• Premium Cabin Styling: Add a short-throw STX Shifter® (reduces throw by 12% front-to-back and 7% side-to-side), a classic MOPAR pistol-grip handle with a 5-speed inlay, matching shift knobs, custom boots, and dress trim rings.
• SST Premium Fluids: Specialized break-in fluid, transmission fluid, and hydraulic clutch fluids are available to order.

Get a Custom Quote for Your MOPAR Build

Every classic street rod, muscle car, and vintage truck setup is unique. Let our transmission experts configure the perfect TKX conversion kit for your horsepower goals, rear-end gearing, and vehicle chassis.

Click Here to Request a Quote Today