NIPPLE ASSY. 0995969 - Caterpillar

Problem: The oil level in a final drive is too high and the oil level in the hydraulic tank is too low.
Probable Cause:
Illustration 2 g01082212
Final drive and brake group
(3) Duo-cone seal
The brake cooling oil is leaking into the final drive. Duo-Cone seal (3) at the wheel brake has failed.Note: To determine the wheel that is leaking, perform the test in the Braking System, Systems Operation, Testing and Adjusting, "Internal Brake Leakage - Check".Problem: The oil level in a final drive is too low.
Probable Cause:
Failure of the O-ring seal on the final drive housing.Check: Check the oil level in the axle housings.
Illustration 3 g01082213
Location of the filter plug and the drain plug for the front axle housing
(4) Filler