There is a specific component that can ultimately render your final drive motor inoperable. The component in question is referred to as the case drain.

The case drain is solely responsible for the link between the final drive motor itself and the hydraulic fluid chamber. Its primary cause is to catch and collect any internal leakages within the excavator's systems and effectively return the not-so-lost fluid away from the operating final drive motor within the excavator.
Any complications with the function of this component alone can be caused to see faulty final drive motor within your excavator.
A good way to ensure this scenario does not happen to your excavator is to conduct frequent inspections of your hydraulic drain filter or case drain system. Either term is referring to the same component so when you hear either phrase being used you’ll know that they are the same.
Not inspecting your case drain filter means that you run the potential risk of clogging in which the leaking fluid instead of being driven away from the final drive motor in turn coagulates on the important functional component itself. We’re sure we don’t have to get too deep as to why this can be a serious problem for your final drive motor; however, to keep things frank, this coagulation will essentially render your final drive motor as “stuck”.
Clogged or malfunctioning case drain filters are, if not the most, one of the most frequent issues an operator will encounter when dealing with a faulty final drive motor.
While keeping a focus on the case drain filter should be toward the top of the list of priorities for frequent inspection, checking your final drive motor’s gear oil takes a close second. This will ultimately help you keep your excavator running for extended periods without much else.

 Regular Inspections Are Vital For Your Final Drive Motor Longevity

Whether you're working with heavy equipment or a small machine, maintenance is crucial to keeping everything running efficiently. Don't let yourself become another statistic of blown excavator drive motors.
It is a fact that machines are prone to malfunction at some point in their operational existence. The only way to combat deteriorating machine functions is to adequately conduct inspections of vital components and parts catching any risks for complete mechanical malfunctions as early on as possible.
It is a good habit for any sized excavator operator to conduct an inspection before and after a workload is conducted. At the end of the day, this can save you and your excavator from any mechanical problems or from simply not being able to see an operation through to the end.