ZF 4HP22 automatic gearbox

When the auto gearbox is  rebuild, the unit is stripped down, washed in both Safety Kleen and hot wash tanks then the casings are shot blasted with glass bead, then painted. Once “Prepped” the stripped unit is sent to the build area in a plastic tub.

The autoboxes have a fixed set of new parts including friction plates, pump bush, filter, gaskets and seals, Once the parts are picked the first step in the build process is to lay the parts out on the bench for inspection, If they pass inspection they are used again, if not they go in the scrap bin.

Once the valve body is built it is put on our ‘Hydratest’ machine which cycles the valve body up to 100 start stop cycles to check all valves are operating correctly, it also checks all solenoids electronically to ensure they are also operating correctly. When the autobox is assembled we fit a test plate in place of the valve body and do a pressurised hydraulic leak test on all of the clutch packs to check they are correctly fitted and have no leaks.  These two checks with the Hydratest machine help us to identify and potential problems before the box is sent out.

Once built the unit is stamped with a number and a spec sheet filled out giving us info on the unit specification, who built it, when it was built and exactly what parts were fitted.
Supplied with a rebuilt Torque converter.
Supplied with no oil! Need something like 9,1L.