Can anybody tell me what hydraulic oil should be used in a high lift HiRanger bucket unit? The oil that is in it now is red and seems light weight. Other owners have told me they use any standard, universal hydraulic oil, such as HyTran which I keep in stock for farm equipment. If HiRanger is not out of business, I would like to order a service manual for this unit. Along with the HyRanger name it also has the name Altec on it. It was built in 1988. Thanks for any help.