it all depends on the situation. if i need to back down a hill. to say deal with a culvert. i will fully curl the FEL bucket so it is upside down. so when i do use backhoe, the tractor does not slide down the hill. due to front bucket digging in some.
other times. i may tilt bucket slight downward. so i do not push the tractor forward with the backhoe.
some times, i will put front blade almost vertical. so instead of digging in. the blade kind skips on the ground. (perhaps hard dry dirt, that bucket itself can not dig in)
some times, curl bucket fully up. so round bottom of bucket hits ground. so i do not tear up any yard. via the front bucket.
for most part i prefer to take a little pressure off the front tires, but still keep the front tires partially touching ground. due to tilt of the front axle. i see no point and at times trying to raise both front wheels off ground would be dangerous. changes center of gravity of tractor enough. that i just do not like.
when putting out the outriggers, i try to shoot for level. but, pending on conditions and what i need to do. i will live with un-even, trench bottom, and just take a little pressure off the rear tires with the out riggers. to help keep the rear end from sliding back and forth.
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my body can not handle constant jarring. and will slow things down most of the times. but the rare few times that come up. i will go full throttle, and yank and pound. i have enough problems staying up on regular maintenance, i do not need to add to the list of tearing stuff up.
folks have bent there FEL frame. but i would rather bend frame, than risk saftey. i have used FEL multi times. running on one side only, back dragging to front dragging and multi different angles of the bucket. to deal with grading out dirt and gravel driveway / road here on the farm.
and same thing when using backhoe, the FEL bucket some times is not touch on one side.
something to think about, having FEL bucket touch ground. helps extend weight out in front of the tractor. to help counter balance the backhoe on back of the tractor. so the entire tractor does not do a wheely and flip over backwards. have lifted front of tractor up into the air before. though it was much easier, when i did not know any better and made sure both front tires were off the ground and really raised up into the air. while using the backhoe.
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i think OSHO might have a requirement that requires rear tires for 2wd tractors, and for 4wd tractors all 4 tires, to get wheels up off ground. so tractor can not physically drive off, and there be no one at the wheel to stop the tractor.
heck i am guilty, of run away tractor. granted i was trying to get off the tractor when it started moving but *shrugs* all i took was woops hit of the wrong lever and away she goes. perhaps that is reason why some folks slight angle front bucket downwards. so tractor digs into dirt vs possibly driving away.
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besides physical seat time. were experience goes a long ways. another part is realizing what might or could go wrong. and making sure you are aware of possible uth ohs...