Wear on the pump gears and with the mating impeller hub reduces pump capacity and increases pump noise.
These direct replacement and oversized gears are specially designed to improve the fit and durability of the pump-to-torque-converter interface.
Sonnax offers high-quality replacement gear sets for F5 and later E4OD pumps. Two designs are offered: a direct replacement gear set 36438A and an oversized gear set 36438AX-01K. Both meet or exceed OE pump gear performance.
In 1995 the E4OD pump was redesigned to utilize pump gears with 10 lobes on the outer gear. Prior to 1995 the outer pump gear had 11 lobes. The pump casting was also revised. Prior to 1995 the pump casting was designated as E9 or F1. Beginning in 1995 the casting designation was changed to F5 and is currently F8. The E9 and F1 E4OD pumps suffered from low pump output and should be replaced with an F5 or later model pump.
Contact a Sonnax Parts Distributor.