WORKHORSE CUSTOM CHASSIS
Service Manual
2007 W Series
SECTION
7.2
PAGE
458
Automatic Transmission – Allison
2007 W Series Chassis
© 2006 Workhorse Custom Chassis — All Rights Reserved
WSM082106
Manual Downshifts
Manual 5-3 Downshift
1. Place the shift selector in DRIVE.
2. Accelerate the vehicle to obtain FIFTH range.
3. Release the throttle while moving the shift selector to
THIRD.
4. Verify the following conditions:
• The TCC releases.
•
The transmission downshifts immediately to
FOURTH range and then to THIRD range.
• The engine slows the vehicle.
Manual 5-2 Downshift
1. Place the shift selector in DRIVE.
2. Accelerate the vehicle to obtain FIFTH range.
3. Release the throttle while moving the shift selector to
SECOND.
4. Verify the following conditions:
• The TCC releases.
•
The transmission downshifts immediately to
FOURTH range, then to THIRD, then to SECOND.
• The engine slows the vehicle.
Manual 2-1 Downshift
1. Place the shift selector in DRIVE.
2. Accelerate the vehicle until the 1-2 shift occurs.
3. Go to 8 km/h (5 mph) above the 1-2 shift point.
4. Release the throttle while moving the shift selector to
FIRST.
5. Verify the following conditions:
• The TCC releases.
• The transmission immediately downshifts to FIRST
range.
• The engine slows the vehicle.
Coasting Downshifts
1. Place the shift selector in DRIVE.
2. Accelerate the vehicle to FIFTH range with the TCC
applied.
3. Release the throttle and lightly apply the brakes.
4. Verify the following conditions:
• The TCC releases.
•
Downshifts occur in normal sequence and the
transmission returns to FIRST range before the
vehicle comes to a stop.
Manual Range Selection
The shift solenoids control the upshifts in the manual
ranges.
Perform the following tests, using 10-15 percent throttle
angle.
Reverse
1. With the vehicle stopped, move the shift selector to
REVERSE.
2. Slowly accelerate the vehicle.
3. Verify that there is no noticeable slip, noise or
vibration.
