A/T - THM 200C New Design Forward Clutch

Number 87-7-25 Date 5/87

NEW DESIGN FORWARD CLUTCH FOR SMOOTHER
Subject: PARK/NEUTRAL TO DRIVE ENGAGEMENT


1984-87 MODELS EQUIPPED WITH THM 200C (MV9)
TRANSMISSION MODELS: All (Excluding 1984-85 CZ, JY)

BULLETIN COVERS:

1987 THM 200C transmissions are being built with a new design "feed/ bleed" system for the forward clutch.. This system gives more cushioning during forward clutch apply and can be used on certain past models to reduce a harsh PARK/NEUTRAL to DRIVE engagement feel.

Figure 1 - THM 200C Transmission Nameplate:

Figure 2:

DATE OF PRODUCTION CHANGE: (Figures 1 and 2)

August 4, 1986 (Julian date 216), these changes were introduced for all THM 200C models:

Forward clutch assembly, minus check ball in housing (619) Forward clutch piston assembly (623) Additional waved plate (627) Front internal gear (636)

SERVICE ACTION:

1984-1987 MODELS BUILT BEFORE AUGUST 4, 1986 (JULIAN DATE 216):

If a vehicle equipped with a THM 200C transmission listed in SERVICE PARTS INFORMATION has a harsh PARK/NEUTRAL to DRIVE engagement, install the Neutral Drive Shift Package.

1987 MODELS BUILT ON OR AFTER AUGUST 4, 1986 (JULIAN DATE 216):

Models built after implementation of the feed/bleed system can be serviced with individual parts.

IMPORTANT: When servicing the forward clutch, select the correct backing plate (627). Backing plate selection affects piston travel, shift feel and clutch durability.

Figure 3:

BACKING PLATE SELECTION (CLUTCH FULLY ASSEMBLED):

Apply an evenly distributed load in the direction indicated in Figure 3 to remove slack from the clutch assembly. Use 20 lbs (9 kg) of pressure against the backing plate--excessive pressure will cause an inaccurate measurement. With the clutch assembly compressed, use a feeler gage to measure the distance between the backing plate and snap ring. Correct backing plate travel is 0.7 mm - 1.5 mm (0.028" - 0.059").

SERVICE PARTS INFORMATION:

1984-1987 MODELS (EXCLUDING 1984-85 CZ, JY) BUILT BEFORE AUGUST 4, 1986 (JULIAN DATE 216):

PART NUMBER DESCRIPTION

8638957 Neutral Drive Shift Package (Contains Forward Clutch
Assembly Complete, Front Internal Gear and Thrust
Washer)

Figure 4:

1987 MODELS BUILT ON OR AFTER AUGUST 4, 1986 (JULIAN DATE 216):

8648720 Forward Clutch Assembly, Complete
8638956 Forward Clutch Housing Package
8648721 Forward Clutch Piston
8657267 Backing Plate, Selective--Identification 7 (Figure 4)
8657266 Backing Plate, Selective--Identification 6 (Figure 4)
8657618 Backing Plate, Selective--Identification X (Figure 4)
8657265 Backing Plate, Selective--Identification 5 (Figure 4)
8657264 Backing Plate, Selective--Identification 4 (Figure 4)
8639947 Front Internal Gear And Thrust Washer Package

SERVICE NOTES:

Earlier design front internal gears (Service Package Number 8630909) cannot be used with THM 200C models built after August 4, 1986 (Julian date 216).