INTERMITTENT LOSS OF DRIVE CHECK 1-2 BAND STOP

MODELS AFFECTED: 1985-1990 DE VILLES 1986-1990 ELDORADOS AND SEVILLES 1987-1990 ALLANTES

Some 1985-1990 DeVilles, 1986-1990 Eldorados and Sevilles, or 1987-1990 Allantes may experience an intermittent loss of drive condition caused by an out-of-specification 1-2 band stop shifting off location. This causes the 1-2 band apply pin to miss the band during its stroke (reverse gear is not affected).

Production improvements have been developed and will be implemented early in the 1990 model year to prevent recurrence of this condition.

Service Procedure (Figures 1-5):

The 1-2 band stop (139) can be replaced with the transaxle in the vehicle by removing the transmission oil pan (59), and oil filter assembly (58) as listed in the Service Information Manual, then:

1. Using a punch and hammer tap the black plastic adjusting tab into the 1-2 band stop assembly just enough so the stop can be removed with pliers. Refer to Figure 2.

2. Use J-38229 1-2 band stop installation tool as shown in Figure 3 by first putting the 1-2 band stop into the tool, then put the stop into the hole and while pushing on the base, squeeze the handle of the tool until it reaches its preset stop.

3. Cut off the remaining adjusting tab as shown in Figure 4.

IMPORTANT: The 1-2 band stop height can be checked during an overhaul. With the transaxle disassembled, the 1-2 stop must protrude 14 mm (9/16") through the case as shown in Figure 5.

Service Tool Information:

The 1-2 band stop installation tool, J-38229, will be available approximately October 1, 1989 from Kent-Moore at (313) 574-2332 or 1-800-345-2233.

Service Parts Information:

Service Package Contents --------------- --------- 8649302 Stop, 1-2 Band Assembly

For warranty purposes use Labor Operation T5185, 1-2 band stop R&R, at .6 hour (policy code M applies).

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.