Harley jeff is right. you dont need a big fancy 3/4 ton truck to plow with. ..
I've got four plow trucks and my short wheel-base 1/2 ton is the best of them all. The short wheel base puts more weight on the back wheels.
Many 1/2 ton and 3/4 ton trucks use the same front axles and same front springs. Much depends on how the truck was ordered,or modified. Trucks with leafs in front were supposed to have one extra leaf for snow plow use.
I've got a 92 HD Dodge-Cummins diesel W250 with extended cab and 8 foot bed, a 94 Ford HD with 7.3 diesel with extended cab and 8' bed, an 89 GMC Suburban 3/4 ton diesel, and an 83 Chevy K5 diesel Blazer.
The K5 Blazer if by far the best of the bunch. Gets into tight places. Been using it for over 20 years. Will plow snow on rough ground and hills up to around 30" deep. Trans was the weak point until I swapped in a T400. 3.08 axles and T400 trans. Extra leafs in front and quad shocks with the OEM plow package.
The 3/4 ton Suburban is the 2nd best. 3.73 axles and T400 trans. Has the same front axle and springs as the 1/2 ton K5 Blazer.
The two 3/4 ton trucks are worst. They will plow a little more when goiing up hill, but will also slide all over the place going down one. If they were shorter, they'd be better.
By the way, I've found posi-rears in back to be horrible going up icy hills. My Suburban had one and I removed it. Posi makes the both wheels spin and will often send you off the road sideways. In ice, tire chains are the best. Some back roads near me, in the Adirondacks require them during mid-winter. You get a ticket if caught without them.
Yesterday we got over two feet of wet snow. None of my trucks could plow all of it on hills. Many drifted areas were over three feet deep and the stuff was like cement. I broke open the worst areas with a farm tractor and 7 foot snowblower, and then plowed.