Saturn Transmission. Manual - part 28

Copyright © 1999 ATSG

4TH SPEED

DRIVE GEAR

3RD SPEED

DRIVE GEAR

2ND SPEED

DRIVE GEAR

1ST SPEED

DRIVE GEAR

1ST SPEED

DRIVEN GEAR

2ND SPEED

DRIVEN GEAR

3RD SPEED

DRIVEN GEAR

4TH SPEED

DRIVEN GEAR

OUTPUT

SHAFT

Figure 2

INDIVIDUAL DRIVE AND DRIVEN GEAR IDENTIFICATION

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3

3

C V   3

A   

3MP7 0 3 4

1

0

4

SV

SV

2 2

6 1

2 2

6 1

3

3

CAV 4

CAV    3

IDENTIFICATION CODE DESCRIPTION

STAMPED IDENTIFICATION CODE

CAN BE FOUND IN THIS AREA

3    MP7   1   043   0   4

1

2

3

4

5 6

1 = Model Year  (3 = 93)

3 = Plant Code (1 = Spring Hill, TN)

4 = Julian Date (043 = Feb. 12)

5 = Hour of Day (0 = Midnight)

6 = Update Code (Increments 0 - 9)

2 = Model Code:
         MP2 = Base Manual
         MP3 = Performance Manual
         MP6 = Base Automatic
         MP7 = Performance Automatic

Identification "SV" here is 2nd design level

Figure 3

Copyright © 1999 ATSG

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COMPLAINT:

SATURN TAAT

DELAYED AND OR NO REVERSE

CAUSE:

CORRECTION:

SERVICE INFORMATION:

MAINSHAFT NUT

SATURN PART NUMBER

2100680

USING A 23mm. 12 POINT SOCKET

TORQUE TO 111 ft.lb.

Before  or  after  overhaul,  Saturn  vehicles  equipped  with  the  MP6  or  MP7  transaxle  may 
exhibit  a  delayed  and  or  no  Reverse  condition  when  hot.  This  condition  is  usually 
accompanied with a soft or flared 2nd gear upshift. Note: Pressure regulator valve bore wear 
out may also be confused as the cause to this problem.

The cause may be, a loose Mainshaft Nut, as shown in Figure 1, causing a leak in the 2nd 
clutch circuit. When the nut loosens the mainshaft tends to walk back and forth in the mid 
case. This causes a gap between the 1st Clutch and the nut, which is where the leak in the 2nd 
Clutch circuit appears. In Figure 2 the cutaway shows how the 2nd Clutch is fed around the 
outside of the feed pipe for the 3rd clutch. Notice that the area over and under the nut are all 
part of the 2nd Clutch circuit.

MAINSHAFT NUT...............................................................................................21001680

Install a new Mainshaft nut, which has a factory thread locker, as part of every repair. Using a 
23mm. 12 point socket torque the new nut to 111ft.lb.

Figure 1

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Copyright © 2006 ATSG

1st CLUTCH

FEED

INPUT SHAFT

HUB

2nd CLUTCH

FEED

3rd CLUTCH

FEED

MAINSHAFT ASSEMBLED

9

9

1st

CLUTCH

2nd

CLUTCH

3rd

CLUTCH

THE 2nd CLUTCH IS FED 

AROUND THE OUTSIDE 

OF THE 3rd CLUTCH 

FEED TUBE 

THE MAINSHAFT NUT IS 

PART OF THE 2nd CLUTCH 

CIRCUIT. IF IT IS LOOSE IT 

WILL CREATE A LEAK IN THE 

2nd CLUTCH.

Figure 2 

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