Contaminants can enter your gearbox oil by vents or even the fill tube during examining/filling. More often than not, even so, contaminants are the result of ordinary don. The gearbox filter safeguards against these contaminants which will help improve gearbox everyday living. On the list of to start with issues https://filtergearbox94703.blogoxo.com/34261873/filter-gearbox-for-dummies