I have a can of Phillips 66 X/C Aviation Hydraulic Fluid that Id like to use in my Parker 108 series hydraulic pack. MIL-PRF-5606F states that viscosity should be ~15cSt at 38C. The Parker/Olidyne spec is ~35-65cSt. So the Phillips fluid is less viscous and is labeled not for use with natural rubber components. Does anyone know if this fluid is suitable?Can someone recommend an inexpensive, automotive fluid that has proven effective?Much appreciated Joe Czabaranek424DH