Sonnax offers 36947-14 and 36948-22, solenoid regulator valves and their tool kits to salvage worn valve bodies and restore proper solenoid regulator valve (SRV) circuit function in both early- and late-style E4OD and 4R100 units. Bore wear at the SRV reduces oil supplied to the shift, TCC and coast clutch solenoids. This regulated pressure also feeds the intermediate or center support area. The '96-later valve bodies incorporated a two-spool anodized aluminum valve that is prone to flaking of the anodized layer, causing premature wear of valve and bore. The '95-earlier have a three-spool steel valve that wears the bore, resulting in excess clearance when hot.
A wet air test in the location indicated with the valve blocked inward results in leakage out the neighboring line port, or a vacuum test of the balance port gives less than 18" of vacuum.