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A/T - Early Shift Points

88buick04

Bulletin: 88-7125-4

Date: Mar., '88

Ref. No.: 88-110-7125

Corp. Ref. No.: 877121
SUBJECT: "EARLY" SHIFT POINTS - QUAD 4 (LD2) ENGINE

MODELS AFFECTED: 1988 SKYLARKS WITH THE LD2 2.3L QUAD 4 ENGINE (VIN CODE D)
Comments have been received that the 1-2 and 2-3 upshifts happen early or at too low a vehicle speed on 1988 Skylarks equipped with Quad 4 (LD2) engines and 125C (MD9) transaxles. A Shift Speed Chart is printed on page 7A-3 of the 1988 New Product Information Manual for Skyhawk/Skylark.

The 125C model KDC with a 2.84 final drive ratio is used with the Quad 4 engine. It is calibrated for minimum throttle shift points as follows:

1st to 2nd upshift................... 9-12 mph 2nd to 3rd upshift................... 17-19 mph 3rd to 2nd coastdown................. 15-17 mph 2nd to 1st coastdown................. 6-10 mph
Minimum TCC apply.................... 34 mph

Minimum throttle shifts are accomplished by accelerating the car from a stop with just enough throttle opening to make the car gain speed. As throttle opening is increased, the shift points will happen at a higher speed. These speeds may vary slightly from car to car with different engine loads.

Vehicles with shift speeds falling within the above ranges should be considered calibrated correctly and no T.V. cable adjustment should be made to move the shift points to higher speeds.