Drivetrain - Design Changes to Differential Components

BULLETIN NO.: 99-T-12

ISSUE DATE: April, 1999

GROUP/SEQ. NO.: Transaxle-03

CORPORATION NO.: 99-04-18-001

SUBJECT:
Service Information on Design Changes to Differential Components on Manual and Automatic Transaxles

MODELS AFFECTED:
1991 - 1999 Saturn vehicles equipped with manual (MP2/MP3) transaxles or automatic (MP6/MP7) transaxles

PURPOSE:

A change has been made during the 1999 model year (built after and including VIN XZ230715) to the differential assembly components for MP2/MP3 manual transaxles and MP6/MP7 automatic transaxles. In order to reduce wear on the components, the pinion gears and pinion shaft have been modified.





The lubrication grooves on the pinion gear shaft have been eliminated and the heel chamfer on the pinion gears has been reduced. The new differential pinion shaft (P/N 21003632) and the new differential pinion gear (P/N 21005842) will be referred to as the 2nd design components. The previous design pinion shaft (P/N 21003293) and pinion gear (P/N 21001012) will be referred to as 1st design. Refer to illustration for comparisons between the 1st design and 2nd design components. The 2nd design components will be serviced in the Differential Assembly Kit (P/N 21005843).

IMPORTANT:
Do not mix 1st design and 2nd design pinion shaft and pinion gear components. Any necessary repairs to pinion shaft or pinion gears will require replacement of components as a kit.

PARTS REQUIREMENTS:

21005843 Kit - Diff Asm