Tow vehicle question

I'd like to upgrade our tow vehicle one of these days. My 150 STX is a little underpowered four our TT. I pulled a 21' bass boat with a undersized GMC Jimmy for years, so I'm used to the extra weight back there. I'm looking to bump up to a 3/4 ton, diesel. We can't really afford to buy new, and don't really want to, as the truck is basically just driven when we pull the camper. Sometimes on the weekend just to run it. Just wondering what your opinion is on mileage. I know you have to do your homework and I know a diesel truck will deal with high mileage better than gas. I've never owned a diesel vehicle before but I've seen that they will run up very high mileage and keep going. I guess my question is... What is considered "high mileage" on a diesel truck. I know there's a difference between "highway miles" and "city miles" but I figure a diesel truck is built pretty much for work anyways. Thanks for your opinions  

Maintenance plays a lot in the mileage I think, obviously if someone has records on a 200,000 mile truck I would feel a lot better about it than one that didn't have the records.
I just traded in my 2004.5 Chevy 2500 Duramax with about 175,000 miles on it. The dealer was able to sell that truck in under a week with it listed at $16,500. I had most of the maintenance records when I purchased it used with about 140,000 miles on it and had everything I had done to it. That really helped in the trade in process.

Please do your homework whatever brand you decide to go with. Each of the big 3 have had issues with certain years\motors\transmissions. There is a lot of good info out on the internet about all this.

I agree that maintenance is a big issue and the cost that goes along with it. A diesel is meant to be driven and since the introduction of the low sulfur fuel, there is a tremendous problem with the fuel "jelling" due to bacteria growth.

I talked with a diesel mechanic friend of mine just the other day who told the story of a customer that had added "bad" fuel to his rig. It cost him over $15,000.00 to replace all the injectors (dealer wanted $19,000.00) to get the rig to run again.

Don't know about you, but that kind of cost would make me sick (and broke).   

Just something to consider . . .

What size, weight..  camper are you towing with the Ford STX?  I have a 2013 F150 that works quite well pulling my trailer.

Our camper is around 4700lbs "dry weight". The truck is rated for 6200lbs but it has the smaller 4.6L engine. When we are loaded up, we're not overloaded, but we're probably on the upper end. We like to camp a lot in the Western NC mountains and the smaller engine is just a little under powered. It does OK most of the time but those 8% grades through the Nantahala National Forest on our way to the Georgia Mtn. Fairgrounds worked it really hard.

Depending on your budget, some of the early ecoboost f150's will be coming off lease or popping up on used lots as trade ins soon. We're actually looking at trading ours soon as the DW wants back into an SUV.

The ecoboost really puts out the torque at the low end of the rpm range similar to a diesel. Properly equipped they can be rated for 9000+ lbs of towing.

OK.. My 2013 STX is rated to row 8100 lbs.. My camper weighs about 4700 loaded up.