TH400 Transmission Holding Fixture Engine Stand Adapter

This is the adapter plate that turns a standard rotating engine stand into a transmission rebuild stand. The case bolts to the fixture through the bellhousing pattern, the fixture slides onto a 2-3/8 inch engine stand post, and the stand's own crank handle then rotates the whole transmission and locks it wherever you want it. Fitment covers the GM family: TH350, TH400 (3L80), 200-4R, 4L60E and 4L80E. Manufacturer part number is TH400.

The reason this matters on the bench is access. Working a transmission flat on a bench means you fight the pump on one end and the valve body on the other, and you end up rolling a 150 pound case by hand every time you need the other side. On a stand you spin it nose-up to pull the pump and drop the drum stack, spin it pan-up to pull the valve body and check the accumulator pistons, and spin it back down to set end play. Nothing shifts while your hands are inside it.

The frame is wide on purpose - narrower fixtures foul on the larger GM cases. It is high-strength iron and rated to hold heavy units like the 4L80E without flexing at the post. There is a reinforced hoist loop welded into the plate, so you can hang the transmission off a cherry picker or shop crane and walk it onto the stand post instead of trying to muscle it up there. The fixture ships as the adapter only - you supply the engine stand and the case bolts.

Check your bellhousing pattern before ordering. A BOP or Buick/Olds/Pontiac pattern TH400 does not share the Chevy bolt circle, and the fixture is drilled for the GM pattern listed above.