Servo Transmission C4 TO4 is specially formulated to meet the optimum frictional requirements of Caterpillar transmission. It meets TES 228 specification of Detroit Diesel Allison Division of General Motors and Caterpillar TO-4 specification. Servo Transmission TO-4 SAE 50 is formulated to meet the optimum frictional requirements of Caterpillar transmission. It meets the requirement of Caterpillar TO-4 and also TES 228 of Detroit Diesel Allison Division of General Motors. It is recommended for use in earth moving equipments fitted with Caterpillar transmission.