I get your point about wanting 400 hp to move a hoe that size but unless you have good size hills it's a non issue to me while I agree everything is priced to high at the moment I have spotted some decent tandems under 30 grand with c12 3306 ism l10 to name a few and for the most part are good engines
I have a buddy that does pools he has a ford with a 3208 and pulls a 314 with a hammer on it I have also pulled backhoes on a service truck and tag with a dt 466 now I know that's not a fair comparison but both those motors are rated under 300 hp and do an ok job it's not a hot rod
Point is when buying used trucks beggers can't always be choosers and if the difference is keeping money in your pocket and taking an extra 20 minutes to move a machine or have payments so you can pass other trucks on the freeway I will be cheap
Also it is not that big of an undertaking to put a hitch and airlines on a truck if you have more than 2500 into it something may have gone wrong
If you buy an older truck and take care of it do the little extras to keep it in good shape they last a long time and most of all it is paid for work or not it can afford to sit there
We don't have that many hills here and most of my moves are in the city, but right now i'm pulling it with 330hp with a 6 speed allison and I know it's pushing the truck right to the limits. I know a standard will have more power, but i'd be scared of killing a 20 year old 300hp motor trying to pull that much weight. Old truck was a 1989 INT with the 400 Cummins and had about 600k miles on it and even just at 50,000lbs it was enough for that truck, the motor was tired. I don't care how fast it moves it, I just don't want something that i'm going to kill in short order pulling the hoe.
Again maybe i'm just scared of old trucks, but i'm worried about trying to drill into a old frame like that and throw on a hitch and stress it in new ways. The old INT was a double frame and it was cracked and splitting in numerous places. Plus i'd rather just put that extra money into the purchase price, if i'm only spending $15k an extra say $3k goes a long ways. It cost me about $1200 for parts and labour alone just to run air lines for my trailer, the trolley lever and trailer button was already there.