I have a 07 400 auto, my question what are the times that I should use Low range? If I was climbing a hill wouldn't the clutches automacticaly shift to low?--Thanks--Mike

 

I like to use low when i'm goin through some really technical terrain like rock crawling. It's also pretty handy when I'm busting through some heavy brush and I want to go slow so I can back out of it if I have to.
I hardy ever use it to climb a hill though. IMO, If you have to switch to low to climb a hill then the hill is too steep to be climbing.

Oh yeah,I always use it when I'm going up my ramps into my truck.

 

another good rule of thumb is when your giving the bike a lot of gas and its hardly moving in any situation...it would be wise to put it in low. usually i use low in mud, rock crawling,tree climbing, hauling a trailor(16 ft) load of wood, riding in the woods(not on a trail).

 

If the terrain 'requires' a speed of 5mph or slower it is a pretty good idea to be in low-range. Another general situation would be that if the terrain 'requires' 10mph or slower it is also a good idea to keep it in 4 wheel drive. There are exceptions to the above as with everything.
The thing to keep in mind is no matter what you are doing you want the clutches to be fully engaged. Too slow in high range and they won't be fully engaged.