A/T - Vent Pipe Oil Leak

Number: 84-148

Section: 7A (VIIc)

Date: June, 1984
Subject: TRANSMISSION OIL EXHAUSTING OUT THE VENT PIPE


Model and Year: ALL 1983 AND 1984 THM 200C
TO: ALL CHEVROLET DEALERS


If a 1983 or 1984 THM 200c transmission exhibits oil exhausting out the vent pipe, possible causes may be due to out-of-flat conditions on the face, nicked faces, porosity, or face damage on the pump body assembly or the oil pump cover assembly.

When servicing any 1983 or 1984 THM 200C transmission for transmission oil exhausting out the vent pipe, both the pump body assembly and the pump cover assembly should be replaced. At the same time, a new pump to case gasket should also be installed. Replacement of these parts will prevent transmission oil from exhausting out the vent pipe during harsh deceleration or during sharp turns.

The following part numbers can be used to service all these THM 200C transmissions.


PUMP BODY ASSEMBLY


Models Order Service Part

BH, PS, CZ, JY,


OI, OR, OU 8638922


OIL PUMP COVER

Models Order Service Part

CZ, JY 8633956

OR, OU 8633957

BH, PS, OI 8633958
PUMP TO CASE GASKET

Models Order Service Part

BH, PS, CZ, JY,


OI, OR, OU 8633899


Refer to your service manual for disassembly and reassembly procedure.