SBC 85-older Tremec T56 6 Speed Transmission Install Kit, 700 HP

This install kit is built specifically for 1955-1985 Small Block Chevy engines that use a 2-piece rear main seal, centered on a TREMEC T56 Magnum 6-speed with a 700 lb-ft torque capacity and shifts up to 7,800 RPM. Displacements covered include 283, 305, 307, 327, 350, the 383 stroker, and 400 cubic inches.

Why the rear main seal generation matters more than displacement

Small Block Chevy engines changed rear main seal design partway through production, and this kit is machined specifically for the earlier 2-piece style, so a block with a later one-piece seal will not accept it the same way. Checking your engine's seal style first catches a fitment issue that displacement alone will not, since several of those cubic-inch sizes were produced with both seal styles over the years.

What is included and what is not

Synchronizers built from carbon and sintered bronze ride inside a steel bellhousing, backed by a billet steel flywheel, a hydraulic throwout bearing, and a performance clutch assembly, with pigtails wired in for the reverse light, reverse lockout, and electronic speedometer. Driveshaft work, a slip yoke, a transmission mount, and a crossmember are left for the installer to source on the chassis side.

What warranty comes with this kit? Coverage runs 1 year for defects tracing back to materials or how the kit was assembled, as long as installation was done correctly.