hello, I have a problem with my manual kubota L2850 dt, I have had problems with the hydraulic system, I changed the hydraulic oil, with kubota super udt2, and the hydraulic system works 10 minutes, and then a sound starts in the hydraulic pump, and I have been doing some research on the viscosity of the oil and the temperature, I live in miami fl. sometimes it's 100°F. Should I use an oil with a higher viscosity grade? I appreciate any advice or recommendation thanks