Welcome to iRV2. Assuming the jacks are hydraulic (not electric) the reservoir should be right next to the pump. The pump would have a line going from the pump to the reservoir. The reservoir will have a screw on cap for checking/adding fluid. Worst case, follow the line from the pump to the reservoir.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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