just got a 955l 85j and 977l 11k -wondered what cat put in the powershift fluid when new? Thanks.
Caterpillar used Series-3 30w Oil in the engine and the transmission and Series-3 10w Engine Oil in the Hydraulic System.
The latest recommendation for 955L/977L before the models were discontinued was EITHER an SAE30 CD-category engine oil provided that it met the requirements of TO-2 specification, or a dedicated TO-2 power train oil of SAE30 viscosity. This was back in the day when "one size fits all" was the mantra and manufacturers were bending over backwards to try to make it that you could top up every system on a machine from a single drum of oil. Well those days are long gone and we are more into "horses for courses" regarding lubricants. So the current recommendations for both machines would be an SAE30 Power Train oil meeting Caterpillar TO-4 specification.