N-1,1-2 HARD SHIFT 1-2,2-3 GEAR CLASH. Pontiac Sunbird 1984

For 1990-2009 cars

# N-1,1-2 HARD SHIFT 1-2,2-3 GEAR CLASH

"Please discard previous bulletin 83-T-53A Section 7 titled Difficult Shifting or Gear Clash - 1983 2000 With Five Speed"

Some comments of difficult shifting into 1st or 2nd and gear clash when upshifting into 2nd or 3rd on 1983-84 2000 vehicles with five-speed manual transmissions have been received. This may be caused by input shaft bearing pre-load. If the clash does not occur with a fast shift, or disappears when the transmission warms up, the condition is very likely caused by input shaft bearing pre-load.

These conditions can be corrected by reducing the input shaft shim thickness. in December of 1982, production began using a reduced shim of .04. These transaxles are identified by a green dab on the rear cover.

These conditions can usually be corrected without removing the transaxle from the vehicle, in the following manner:

1. Raise vehicle on a frame hoist - leave transmission in gear.

2. Remove the left front wheel.

3. Remove inner fender plastic splash shield.

4. Remove transmission rear cover and gasket shown on page 13 of Shop Manual, Section 76mm Manual Transaxle. It may be necessary to bend the sheet metal slightly.

5. Remove shifter fork pin.

6. Remove nut from end of output shaft - impact wrench works best.

7. Remove synchronizer and fork together with needle rollers.

8. Remove nut on end of input shaft.

9. Remove gear and rear plate. Bearing and shim pack will be exposed.

10. Remove input shaft shim. Replace with a shim that is the minimum thickness without causing axial movement of the input shaft.

11. On reassembly, apply Loctite or equivalent to input and output shaft nuts. Also stake bearing retainer to transaxle case screws (Part Number 94248159).

There should be no input shaft axial movement after rear plate is replaced. Procedure may be repeated, if necessary, as long as the input shaft does not become loose. Below is a list of shim part numbers and their thickness:

M200 INPUT SHAFT SHIMS

PART NUMBER THICKNESS ----------- --------- 94115571 1.00mm 94115572 1.08mm 94115573 1.16mm 94115574 1.24mm* 94115575 1.32mm* 94115576 1.40mm* 94115577 1.48mm* 94115578 1.56mm* 94115579 1.64mm* 94115580 1.72mm 94115581 1.80mm 94115582 1.88mm 94115583 1.96mm 94115584 2.04mm 94115585 2.12mm 94115586 2.20mm 94115587 2.28mm 94115588 2.36mm 94115589 2.44mm

*Most commonly used shims.

Labor Operation Number: T0121 Labor Time: 1.1 hrs.

#### NOTICE: Item #47 is the input shaft bearing shim. The service manual incorrectly identifies it as the output shaft bearing shim.

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.