Your Powertrain Starts With the Right Transmission

Choosing a gearbox involves more than picking a model number. The transmission needs to match your engine output, suit the chassis it is going into and deliver the right combination of ratio spacing, cruising RPM and shift behaviour for the way the vehicle will be used. A close-ratio Tremec T-56 that works well on track can leave a road car sitting at uncomfortable motorway RPM, while a deep overdrive automatic that cruises quietly may feel sluggish in a lightweight build.

This page covers the full Tremec manual range and the complete GM SuperMatic automatic line-up, along with the controllers, bellhousings, clutches, converters and installation hardware needed to complete any build. Use our ratio calculator to model your setup before committing, or contact us for a tailored package.

Tremec Manual Transmissions

T-56 Magnum

The benchmark six-speed manual for high performance V8 applications. Rated to 700 Nm in standard form, the T-56 Magnum handles naturally aspirated and moderately boosted LS and LT engines with consistent engagement and predictable shift quality. Available in GM and Ford input configurations, with close-ratio and wide-ratio gear sets offering either tight track spacing or deep overdrive cruising. Multiple shifter positions and slip yoke or fixed yoke output options cover a wide range of tunnel and driveshaft configurations.

Magnum XL

A strengthened evolution of the T-56 platform with increased torque capacity, improved synchroniser design and a wider selection of ratio options including a 0.50 overdrive sixth gear. Designed for builds where higher output or heavier vehicle weight demands additional internal strength, while retaining the same external dimensions and mounting pattern as the standard Magnum.

TKX

Compact, lightweight and purpose-built for conversions where tunnel space is limited. The TKX is shorter and narrower than the T-56, making it an excellent choice for British classics, kit cars, restomods and smaller chassis layouts that still need modern strength and smooth shift quality. Available with a range of input spline configurations for LS, LT and Ford applications.

TR-6060

A heavy-duty six-speed with a wide gear contact area and robust synchroniser design. The TR-6060 is the strongest manual in the Tremec line-up and is often chosen for turbocharged builds, supercharged applications and vehicles that see sustained high-load use. Originally fitted to high-output OE platforms, making it well understood and widely supported.

GM Automatic Transmissions

4L65-E, 4L70-E and 4L75-E

Four-speed automatics from the SuperMatic range, ideal for moderate power builds where cost, packaging and parts availability are priorities. The 4L70-E and 4L75-E include strengthened internals and improved valve body calibration over the base 4L60-E. Popular for classic conversions, daily-driven repowers and builds that do not require six or more forward speeds.

4L80-E

The standard choice for high-torque applications. Built around a heavy-duty gear set and oversize clutch packs, the 4L80-E handles boosted LS builds, heavy vehicles and off-road conversions without difficulty. Known for predictable behaviour, internal strength and broad aftermarket support for further upgrades.

6L80-E and 6L90-E

A refined six-speed platform with adaptive shift logic, efficient ratio spacing and excellent road manners. The 6L80-E is increasingly popular in LS and LT repowers where smooth, modern driving behaviour is required. The 6L90-E adds additional torque capacity for heavier or higher-output applications.

8L90-E

An eight-speed automatic with rapid shift response, tight ratio spacing and strong torque management. Delivers both performance and refinement, with low cruising RPM in eighth gear making it well suited to LT-powered road cars, GT builds and long-distance touring applications.

10L80-E

The most advanced automatic in the GM range. Ten forward speeds provide continuous torque delivery, extremely low cruising RPM and seamless shift behaviour. A compact package with exceptional efficiency, suited to contemporary LT builds where the transmission needs to match the sophistication of the engine.

Transmission Control Systems

Every GM electronic automatic requires a standalone controller or CAN integration module to operate outside its original vehicle. We supply complete controller kits from the SuperMatic programme alongside aftermarket TCMs, plug-in wiring harnesses, paddle-shift modules and calibration hardware. These systems support LS and LT engine management integration, making them suitable for older platforms that never had electronic transmissions as well as modern custom builds that need full shift control and diagnostic capability.

Installation Hardware

Flexplates, crank adapters, slip yokes, output flanges, crossmembers, transmission mounts, clutch packages, hydraulic systems, shifter assemblies and specialist fasteners. Every component needed to complete a full installation, whether you are building a straightforward repower or a fully engineered custom drivetrain. All hardware is selected for correct fitment with Tremec and GM transmissions paired with LS and LT engines.