540b hydraulic issue

[Oliver05262]

  Hygard is Deere's trade name for the hydraulic oil they specify. A number of suppliers make oils that they claim to meet that spec. In a newer machine with highly loaded components, it probably is advisable to stay with the manufacturer's oil, but in an older machine such as yours, perhaps not so much.
  If the oil you choose says on the container that it meets Hygard specs it is probably a safe substitute. JD 303 is an older specification that you might want to take a pass on.
  The friction modifiers in the Hygard spec oil work well with the wet brakes and the power shift clutches in the transmission. Problems with off-specification oils can be seen in grabby or noisy brakes and/or aggressive shifts in the tranny.

[Southside]

Can you even buy 303 any longer?  It's not around here now.  If you think Hyguard is pricey you don't want to be around my Super 70 when I break a hose, it calls for a special multi-viscosity oil with gold flakes in it or something, $300 a 5 gallon pail.   

[mike_belben]

Nope.. 303 is all gone around here.  Used to get it for $19 a pail in 2018 or so. Cheapest thing i can find now is $30ish. 

[newoodguy78]

I was just reading there's a class action suit going on in regards to 303 and the problems it created from using it.

[Oliver05262]

Tractor Supply has it around here. It isn't good for a whole lot more than the AW32 or AW46 hydraulic oils, but people read the John Deere name on the labeling and use it where they shouldn't.

[teakwood]

If you think Hyguard is pricey you don't want to be around my Super 70 when I break a hose, it calls for a special multi-viscosity oil with gold flakes in it or something, $300 a 5 gallon pail.   

Hyguard is actually cheap here, 95$ a bucket (5gal), i put Mobil DTE Exel 68 in my excavator, last time it was 1400$ a drum (140$ a bucket)