Keep in mind that when the gearcase is full of fluid, the fluid level should be just below the stub shaft (pto) when the tractor is level. I agree the dipstick is puny and hard to read which i one reason why I use Chevron THC synthetic all weather fluid. It comes dyed orange of all things and the cold weather flowability is better than the SUDT is. It's also as expensive as the SUDT in 5's. My old eyes cannot see the fluid level with SUDT in the gearbox anyway. Why I punched holes at the min and max marks on the dipstick 1/16th inch holes will bridge with fluid and make it easy to see the actual fluid level.
Don't want mine overfilled anyway because I exchange PTO stub shafts pretty regularly. My HDCC3 has the 2 speed pto option but it's a shaft exchange (540- 6 spline and 1000 21 spline). I use the 21/1000 shaft when running less power intensive implements like my hay rake or grain leg because I don't need to run at rated rpm to achieve 540. The motor is out of it's torque rise idled down but those implements don't demand a lot of power to run anyway.
If the fluid is above the pto stub when the tractor is level, exchanging shafts can be very messy (fluid runs out) so I keep the level at the bottom of the stub shaft to eliminate the mess. I still back the tractor up on ramps, nose down when I change out the shafts as a precaution. Not into making a mess on the concrete.
