SBC 86-up Tremec TKX 5 Speed Transmission Installation Kit, 500HP

A TREMEC TKX 5-speed manual sits at the core of this kit, carrying a 600 lb-ft torque rating and shift capability up to 7,500 RPM, with engine speeds supported up to 8,000 RPM. Performance Automatic recommends it for engines producing roughly 500 horsepower or less, in 305 and 350 TBI or Vortec Small Block Chevy applications with a one-piece rear main seal.

Five forward gears in a compact case

Rather than the larger case a six-speed gearbox needs, the TKX uses a shorter, more compact aluminum housing that leaves generous transmission tunnel clearance, while its overdrive fifth gear still knocks down highway RPM on long drives. The 11-inch performance clutch kit bundled here is sized to match that compact case rather than a bigger unit.

What is included

The bellhousing, flywheel, clutch, and hydraulic release bearing are all installed as part of the package already, alongside the pilot bearing, mounting hardware, and wiring pigtails for the reverse light and electronic speedometer. Because Chevrolet moved to a one-piece rear main seal starting with the 1986 model year on these engines, an earlier two-piece-seal block calls for a different kit entirely.

Does this fit an older, two-piece rear main seal Small Block Chevy? No; confirm your engine's seal style with us before ordering, since this kit is matched only to the newer one-piece seal design, and coverage runs for 1 year against material and assembly defects when installed correctly.