Usage:
135H (3YK1-UP, 7MM1-UP, 8WN1-UP),
12H (2GS1-UP, 2LR1-UP, 2WR1-UP, 4ER1-UP, 4XM1-UP, 5ZM1-UP, 8MN1-UP),
140H (2ZK1-UP, 3AS1-UP, 3FR1-UP, 5HM1-UP, 8JM1-UP, 8KM1-UP, 9TN1-UP, 9ZN1-UP),
143H (1AL1-UP),
160H (2HS1-UP, 2FM1-UP, 3GM1-UP, 3HR1-UP, 6WM1-UP, 9EJ1-UP, 9JM1-UP),
163H (5AK1-UP) MOTOR GRADERS
Problem:
There have been reports of transmission clutch failures caused by a bond failure of the disc material. Friction discs returned from the field have verified a very small number (less than ten) of bond failures. These failures occurred on discs with a date code of 1995 to 1999. The date code appears on the teeth of the disc. The other failures thought to be bond failures were actually fatigue failures of the disc material caused by clutch slippage.
Solution:
The supplier of friction discs has made a process change to improve bonding. The change involved the adhesive and the application of adhesive. The new adhesive material is readily identified by its black color, and will have a date code of 2000 and higher. The former adhesive was reddish-brown in color.
To determine if a bond failure has actually occurred, use a razor knife along the edge of the friction material to try to pop it off the plate. If there is a bond failure, the material will pop off very easily with no friction material and/or adhesive left on the plate. The plate surface will look like the surface of the teeth. When a bond failure has been confirmed, the friction discs in all the clutches should be examined, and replaced if necessary. A bond failure could be caused by water in the transmission oil. Be sure to check the oil for water and correct any problems that might allow water entry.
If no bond failure has occurred and fatigue was the cause of the clutch failure, try to determine the cause of the clutch slippage. Some potential causes are low clutch pressure or slow clutch fill times. Low pressure could be caused by one of the following problems: an improperly adjusted valve, a solenoid problem, a clutch piston seal leaking, or a rotating shaft seal leaking. Slow fill times could be caused by a low initial pressure setting, plugged modulation valve orifice, or oil leakage.
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