Lost the old rig time to rebuild

your a little out in the cost of a diesel.  yes they cost 5 to 8K more to buy, but there is less than half the maintenance on them, and the fuel savings alone coverers that if you were disciplined enough to put those penny's away.

for example with my old trailer I had a gasser and I would get about 8mpg towing with it (trailer was 1500 lbs under the capacity of the truck) because you are towing you now go by the "extreme" category in the maintenance schedule.  I switched to a 3/4 ton diesel and the only maintenance was filter and fluid changes.  yes the oil change was three times the price but it was half the frequency so only a little more expensive, filters cost close to the same, but yes the diesel was a little more in filter costs, not much.  the difference is I went from 8 MPG to 18 MPG toing that trailer AND diesel was $0.10/L cheaper than regular gas (37.8 cents a gal cheaper).  now, its a little more than gas which is weird.   I also do a lot of longer trips, so 1000 miles return with no extra driving but when we go see the older boy that turns into a 2500 mile trip we do ones a year over a couple weeks.  so that would have been 312 gal of gas in the old truck in the old diesel it was about 138 gal of gas, plus the diesel was much nicer to drive.  so up here out gas (cheapest price from Costco is 3.49 US for a US gal, and diesel is 3.84 US for a US gal.  taking todays pricing I would have spent 1089 bucks US for that trip in gas.  with the diesel the same trip would cost 530.00 US.

now with campers there is a difference also, not as big, but with my new diesel I get 14mpg (US) towing the 40 foot 5th wheel, with my truck camper in it driving at 65mph on average, am getting 19mpg.  if I slow that down to 55 I jump into the 20mpg range.  I do have it tuned with emission on tunes which helps, and when I finish the deletes and switch to emission off tunes (because I can do that where I live) I will probably jump 1 or 2 mpg more.

what is really nice is to be able to leave my house heading west.  I have a 12 mile grade 8 climb, then I still climb over the next 50 miles, and the truck engine isn't screaming and I can easily maintain the 70mph speed limit if I want.  also the convenience of using truck stop and high flow diesel nozzles is nice also.  easy as pie when you are towing a trailer.