The main thing isn't what the diesel "can't" do, it's more, what it doesn't "NEED" to do, which is pull light trailers, plow snow and run to and from Hayward at 1,000 miles a trip, 2-3 times a MONTH, most of the time empty or with a sub 3000# trailer. Ask anyone who's been up to my place in Hayward, up until the F350 I've used the shit out of my trucks up there, back in the field, out on the trails cutting trees, etc... They get beat up and abused as well as a metric shit ton of miles put on them. For now I've gotten by using my ATV with a 4x8 trailer up there, but I'm to the point of buying a SxS to use up there, but the questions comes of why... The SxS I'd get for up there would cost about the same as a four year old truck with low 100's on the clock and can be street driven and used, so to me it makes sense.
It comes down to this, I'm not going to mile out and beat up a truck that would cost $70,000 to replace when I have the option to spend $12-15,000 on a 2nd truck that can also make me back SOME money via snow removal, get beat up and have 35-40k of the 50k I drive annually on average and prolong the life of the F350 for pulling the boat, heavy trailers (it'll be getting a 5th wheel setup soon) and for when I just feel like being in something nice.
If you figure 5 years of ownership at my average driven mileage (50,000/yr, technically a little higher but we'll use that for easy numbers) if I buy a brand new $70,000 6.7 PSD that truck will be worth about $20,000 with 250,000 miles on it, judging on current market values of the trucks with said mileage. Now, if I only put 75,000 miles on the same truck in that time, it'll be worth roughly $45,000
We're really only talking about two trucks here, the F350 and whatever newer gasser I add to the fleet. The Suburban will be sold to a friend of mine who is in love with it and is willing to fix the things it needs, and the Yukon Diesel project will be a long time in the making, eventually just becoming a "toy". I'll summer DD the DuraKon once it's finished, but, it won't be a winter vehicle, and will probably receive some performance parts and simply used like anyone else who has a Corvette/Camaro.
Ask and you shall receive lol.