My dealership did the service. We had oil samples run on the fluids and everything came back within specs. I asked for that because I am use to maintaining a fleet of heavy equipment and we do that every oil change. Not sure what they use but it should be manufacturer recommended. Singleton's are pretty reliable so I'm sure it's the right type.
Funny you mention the tire pressure. I called Singleton's this morning after finding pressure on my transmission when checking the fluid level. When I unscrewed the dipstick for the tranny there was a fair amount of pressure that released. The tractor had sit all night without being started so I knew something was up. Anyway, after pulling the breather on the rear of the tractor for the tranny, I couldn't blow through it at all. I finally got it cleaned enough to vent and reinstalled. When I called them, they told me to check the tire pressure regarding the whine. I'm embarassed to say that I run 32 lbs front and back (and wonder why the tractor is so rough...). Mr. Mike told me to run no more than 15 rear and 20 front. He said 10 rear and 15 front should be enough! I checked my psi and LR was 30, RR was 18, LF was 10, and RF was 27! I bled them all down to what he suggested and the ride improved, but I have not been able to test the gear whine yet. I am going to fill all four tires with water tomorrow and see what it does.
I guess a little maintenance goes a long way!
Thanks for the replies.