WORKHORSE CUSTOM CHASSIS
Service Manual
Automatic Transmission – Allison
2007 W Series
© 2006 Workhorse Custom Chassis — All Rights Reserved
SECTION
7.2
PAGE
467
2007 W Series Chassis
WSM082106
• Damaged or worn seal
• Improper installation
• Cracks in component
• Manual or output shaft surface is scratched, nicked, or
damaged
• Loose or worn bearing causing excess seal wear
CASE POROSITY REPAIR
Some external leaks are caused by case porosity in
non-pressurized areas. You can usually repair these
leaks with the transmission in the vehicle.
1. Thoroughly clean the area to be repaired with a
cleaning solvent. Air dry the area.
CAUTION:
Epoxy adhesive may cause skin irritations
and eye damage. Read and follow all informa-
tion on the container label as provided by the
manufacturer.
2. Using instructions from the manufacturer, mix a
suffi cient amount of an epoxy to make the repair.
3. While the transmission case is still hot, apply the
epoxy. You can use a clean, dry soldering acid brush
to clean the area and also to apply the epoxy cement.
Ensure the area to be repaired is fully covered.
4. Allow the epoxy cement to cure for 3 hours before
starting the engine.
5. Repeat the fl uid leak diagnosis procedures.
AUTOMATIC TRANSMISSION OIL COOLER
FLUSHING AND FLOW TEST
GM studies indicate that plugged or restricted
transmission oil coolers and pipes cause insuffi cient
transmission lubrication and elevated operating
temperatures which can lead to premature transmission
wear-out. Many cases could have been prevented
by following published procedures for transmission
oil cooler fl ushing and fl ow checking. This procedure
includes fl ushing and fl ow checking the auxiliary
transmission oil cooler, if equipped. GM requires that
transmission oil cooler fl ushing and fl ow checking be
performed whenever a transmission is removed from the
vehicle for service within warranty, including:
• Goodwrench SRTA
• Major overhaul
• Torque converter replacement
• Oil pump replacement
Only GM Goodwrench DEXRON® VI automatic
transmission fl uid should be used when doing warranty
repair on GM transmissions.
TOOLS REQUIRED
• J 35944-A Transmission Oil Cooler and Line Flusher
• J 35944-22 Transmission Oil Cooler Flushing Fluid
• J-44835-1 Transmission Oil Cooler Flusher Adapters
• Measuring cup
• Funnel
• Water supply - hot water recommended
• Water hose at least 16 mm (5/8 in) ID