A/T - 440T4 Buzzing Noise

SIL 88-28 (Aug.)

SUBJECT: THM 440-T4

PROBLEM: "Buzzing" Noise

CAUSE:
May need an orificed cup plug installed into channel plate to stabilize modulator valve action.




When servicing the THM 440-T4 transmission it is recommended to install the orificed cup plug to prevent the possibility of "BUZZING". Any cup plug that fits properly can be used if a .045" hole is drilled into the center of it. The orificed cup plug began use in THM 440-T4 transmissions in 1987. The part number for the orificed cup plug and gaskets needed for its installation is 8646987.