john deere 303

i have been looking around for a 303 spec oil, in doing so i came across an article where a bloke had removed the 303 spec oil that was in it and replaced it with a standard type hydraulic oil and said that the hydraulics operated better,much less noise from the pump and they were quicker.also...

I know it is common knowledge that JD 303 is the hydro-trans fluid of choice. My question to the old heads is, what is the difference between the TF300 and the TF500 that two different tractors I have says to use in their transmissions. There has to be some difference. I know that when I change...