Radiator Control Sleeve (Petcock Valve), BMW - E82 135i, E9X 335i, E89 Z4 35i Manual

This is the radiator drain valve, also known as a BMW control sleeve or petcock valve, for manual transmission E82 135i/1M, E90/E92/E93 335i, E84 X1 35i, and E89 Z4 35i/35is models with the N54/N55 turbo engines and the manual transmission. The blue screw in the center is a traditional drain valve for the complete radiator. The rest of the design controls fluid flow to a heat exchanger for an automatic transmission. Shorter control sleeves for a manual transmission are the right length to block fluid to the heat exchanger outlet on the radiator.

If you remove the valve using the hex portion you will break the tabs that lock the valve in place. The system will never seal again until a new control sleeve is installed. For proper fluid draining unscrew the center blue portion.

This control sleeve is made by Modine, a supplier of cooling system components for over 100 years.