36424-03K E4OD / 4R100, Factory Style Boost Valve & Sleeve.
#20S. Needed for every rebuild, made of better material. Vehicles with an E4OD / 4R100 transmission frequently have problems with poor line rise and / or soft shifts. These complaints are often caused by severe wear of the pressure regulator sleeve, allowing EPC and reverse boost oil leakage. The Sonnax replacement assembly eliminates these problems with a closely toleranced pressure regulator boost valve and sleeve. This valve has been specially coated to eliminate excessive wear. Wet Air Test leakage discovered after correctly installing the Sonnax boost valve may indicate pump cross circuit leaks. A Wet Air Test must be performed on re-machined pumps for verification of flatness. Your transmission will have to be removed to install this valve.