Seville V8-273 4.5L (1989)
Clutch: All Technical Service Bulletins
A/T - 4T60 No Third Gear/No Drive or Reverse Conditions
NO.: 91-I-67
DATE: Sept. 1991
GROUP: 7
CORP. NO.: 077140
SUBJECT:
NO THIRD GEAR AND/OR NO DRIVE OR REVERSE - CENTER GEARBOX DISTRESS DIAGNOSIS TIPS ON ALL 1985-1991
CADILLACS WITH THE HYDRA-MATIC 4T60 (THM 440-T4)
Center gearbox distress in a Hydra-Matic 4T60 (THM 440-T4) transaxle may result in one or more of the following conditions:
1. No third gear due to a distressed third roller clutch cage. Also, slips in third gear or no third gear.
2. No drive or reverse due to a distressed input sprag clutch.
3. Distressed third and input clutch fiber and reaction (steel) plates.
Several aftermarket publications have been written concerning different ways to modify the Hydra-Matic 4T60 or in an attempt to reduce center gearbox
distress. Some of the modifications include grinding slots, lining up lube holes differently, and greatly increasing the fluid level. Do not attempt these
modifications or procedures because they may cause durability concerns.
