TRANSAXLE/ECM PROM COMPATIBILITY

MODELS AFFECTED: 1987 ALLANTE

An ECM PROM and transaxle calibration change was made during the 1987 model year on Allantes. The updated calibration changes allow VCC apply in 3rd and 4th gear only.

Since all exchange transmissions are of the update design, an updated PROM (I.D. 545) must be installed if the original PROM I.D. is 543.

Early production and late production ECM, PROM, and transaxles are not compatible with each other. To determine which ECM PROM must be used with each transaxle I.D., use the following chart:

Latest PROM I.D./ Service PROM Trans. I.D. Broadcast Code Part Number ----------- -------------- ----------- Early Prod: 7AAZ 543/AHWY 16077504 ---------- Late Prod: 7APZ 544/AKAA 16076500 ---------- -or- 545/ADBC

NOTE: Reference Serviceman Bulletin T-87-18A. PROM I.D.'s 544 and 545 are interchangeable and both are compatible only with a second design 7APZ transmission. PROM I.D. 544 is not available as a service part.

For warranty purposes, use Labor Operation J6364 at .5 hour for PROM replacement.

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.