WORKHORSE CUSTOM CHASSIS
Service Manual
Automatic Transmission – Allison
2007 W Series
© 2006 Workhorse Custom Chassis — All Rights Reserved
SECTION
7.2
PAGE
473
2007 W Series Chassis
WSM082106
EXCESSIVE SLIPPAGE AND CLUTCH CHATTER
Condition
Action
Incorrect speed sensor readings
See speed sensor DTCs.
Incorrect fluid level
Correct the fluid level. Refer to Transmission Fluid Checking Procedure.
Main pressure low
Repair the transmission.
TCC clutch not applied
Inspect the torque converter clutch system wiring, pressure, and con-
trols. Repair as necessary.
Ranges 1, 2, 3, 4 Only
1-2-3-4 clutch slipping, leaks at rotating clutch seals, leaks at piston
seals, 1-2-3-4 clutch plates worn
Inspect the 1-2-3-4 clutch plates, and piston and rotating seals.
Replace/rebuild as necessary.
Ranges 4, 5, 6 Only
4-5-6 clutch slipping, leaks at rotating clutch seals, leaks at piston
seals, 4-5-6 clutch plates worn
Inspect the 4-5-6 clutch plates, and piston and rotating seals. Replace/
rebuild as necessary.
Ranges 3, 5, R Only
3rd, 5th and Reverse clutch slipping, leaks at piston seals, 3rd, 5th and
Reverse clutch plates worn
Inspect the 3rd, 5th and Reverse clutch plates and piston seals.
Replace/rebuild as necessary.
Range 2, 6 Only
2-6 clutch slipping, leaks at piston seals, 2nd clutch plates worn
Inspect the 2-6 clutch plates and piston seals. Replace/rebuild as nec-
essary.
Ranges 1, R Only
Low and Reverse clutch slipping, leaks at piston seals, Low and
Reverse clutch plates worn
Inspect the Low and Reverse clutch plates and piston seals. Replace/
rebuild as necessary.
