Your heavy chassis Kubota Grand L - L3010 should be fine on slopes.
Fill the rear tires 3/4 with liquid to lower the tractor's center of gravity. Set the adjustable wheel width to its widest adjustment. You should be ready for any reasonable slopes. With R1/ag tires the rear wheel spread can be v-e-r-y wide. (Potential rear wheel spread widths are shown in your Kubota Operator's Manual.)
(These are the two key recommendations for preparing all traditional tractors for work on slopes.)
Also desirable features for slopes are heavy tractor chassis weight relative to width and 4-WD. Your L3010 has both.
Tractors with less than 80-horsepower sold today are about 90% equipped with HST transmissions. The HST has max torque starting a pull, which is ideal for slopes. Few would argue that HST today is more trouble free than any type of gear transmission and Kubota HSTs have a very good reputation, probably the best in the tractor industry.
A Power Trac tractor would be worth considering if you are mechanically adept, as Power Trac has no dealers. Tractors with four equal size wheels are more stable on slopes but lack the pulling power for ground contact work of traditional tractors with large rear wheels providing mechanical advantage and greater traction on level ground. Implements mostly work off the front, rather than the rear of tractors with four equal size wheels.
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