Some Ford E4OD and 4R100 transmissions have soft 1-2 or 2-3 shifts, intermittent harsh shifts or poor line rise complaints. These can be caused by ECU (electronic control unit) or accumulator pressure problems. Severe wear of the line pressure modulator sleeve allows EPC (electronic pressure control) oil to leak past the valve and cause soft shifts. Severe wear can also cause the valve to stick or hang up, causing harsh shifts. Sonnax line pressure modulator plunger valve kit 36948-03K eliminates this oil loss problem in listed units.

Sleeve is manufactured from carbon steel to prevent excessive wear
Valve is made from hardened alloy steel for better wear resistance
O-Ring helps prevent EPC oil loss.
Annular grooves center valve in sleeve and eliminate sideloading
Improves shift firmness


OE Application
OE Valve Diameter
Sonnax Part No.


6-Cylinder & Small 8-Cylinder Applications
.331"
36948-03K

Large 8-Cylinder Applications
.372"
36948-05K

Heavy Duty/High Performance or Stock AX4N ('97-Earlier) Replacement
.427"
96948-01K

Extreme Heavy Duty/High Performance
.500"
96948-05K



Learn More About Zip Valve™ Drop-In Repairs
Some Ford E4OD and 4R100 transmissions have soft 1-2 or 2-3 shifts, intermittent harsh shifts or poor line rise complaints. These can be caused by ECU (electronic control unit) or accumulator pressure problems. Severe wear of the line pressure modulator sleeve allows EPC (electronic pressure control) oil to leak past the valve and cause soft shifts. Severe wear can also cause the valve to stick or hang up, causing harsh shifts. Sonnax line pressure modulator plunger valve kit 36948-03K eliminates this oil loss problem in listed units.

Sleeve is manufactured from carbon steel to prevent excessive wear
Valve is made from hardened alloy steel for better wear resistance
O-Ring helps prevent EPC oil loss.
Annular grooves center valve in sleeve and eliminate sideloading
Improves shift firmness


OE Application
OE Valve Diameter
Sonnax Part No.


6-Cylinder & Small 8-Cylinder Applications
.331"
36948-03K

Large 8-Cylinder Applications
.372"
36948-05K

Heavy Duty/High Performance or Stock AX4N ('97-Earlier) Replacement
.427"
96948-01K

Extreme Heavy Duty/High Performance
.500"
96948-05K



Learn More About Zip Valve™ Drop-In Repairs