TUBE AS 4479801 - Caterpillar

Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
Final drive may fail on the rear axle on the machines listed above. An extreme event may occur that damages the gears in the final drive. The operator may hear noise from the final drive.Solution
Replace the failed part with the same part number.In order to improve final drive gear life, fill the axle with TDTO 50 weight oil if you were running 30 weight oil previously. If your axle had 10 weight oil previously please fill the axle with 30 weight oil.Note: If your machine runs in an ambient temperature that is consistently under 0 ° C (32 ° F), please continue to use TDTO-4 10 weight oil.Refer to Illustration 1 for the CAT part numbers for each weight oil.
Illustration 1 g06103650