I actually lower my tires to like 2.5 sometimes even 2 just for a bigger print so i can hookup a lil better

 

I usually have about 3&1/2 psi. In the winter, I put between 3&3/4 - 4 psi in the tires.

 

downndirty

I do not think it makes that much of a difference on a 6ply tire, I just try to keep a happy medium of tire pressure in my tires.
Not too much to where I will bounce all over the place and not too little to where I will break a bead.
Besides If i cannot make it with 26 in 589'2 in 4 wheel drive with differential lock, It will not make it by dropping my tire pressure by 1 lb or two... my 2 cents.....

 

i have 6 ply 22 inch bearclaws on my ds they are so stiff i can run 2 and its still fine and it grips really good.......thats a 6ply tire tho

 

Hey HARTKAST. For a two wheel drive quad, I agree with moldycheese. Run more in the front than the back. Reason is, the rear needs more traction, so lower PSI. However, the front plows in the snow if you run a low PSI, so best bet is to run higher in the front. I know it makes a big difference on my quad.
I hope this helps.
BryceGTX