This starts life as a stock ZF transmission 6-speed. It is completely rebuilt to better than stock specs to make shifting smoother and faster.
While the internals are out, all non-friction mesh and bearing surfaces are cleaned through REM® polishing. This isotropic polishing process leaves gears and bearing surfaces mirror smooth, which reduces friction (heat and driveline power loss).
In our cars, we saw a 2-3% reduction in driveline losses on a chassis dyno with this part alone (this equates to 6-10 Hp on an average M3 Prepared class engine!) - plus more time spent accelerating due to faster shifts.
This unit is stock on a e90, e81, e46, z4 non m cars and some others. Call with further questions or specifications. Price does not include $1000 core charge for an acceptable piece (no junk please!). Customer responsible for return core shipping.
We recommend using factory BMW fluid.