Buying older truck with high miles vs newer truck

that was what my 2000 detriot 515 got on our Freightliner Century 6.7 or so. She would at times get into the 8's and once in a while in Western Kansas in spring storms pushing our trailer eastbound would get close to 20 mpg for a few hours.

No emissions anything in those days. Just your normal filter, muffler and pipe. That's it. I did not know this at that time it was a very good truck for what we did with it.

If I had to purchase a truck with a million miles on it plus with someone twisting my arm it's going to be a Cat. That way if I can find someone with a passion and love for Cats in a shop made to work on Cats anywhere that person will enjoy a nice income off taking care of that kittycat when needed to for the big stuff.

Otherwise I'll just drop in a C32 Caterpillar engine into it. Runs between 1600 and 2300 RPM with 750 horses at idle and 1800 horses at 2000 rpm. I might have to custom install a second steer axle to accommodate that nice big kitty.

 

Going from 6 mpg to 7 mpg running 2500 miles per week for a year is $10k.

 

All the emissions stuff can eat that 10 grand up in a hurry.

 

On my planet apparently. I have a friend who has a 2014 Kenworth T680 making 6.4 mpg. I pull the same trailer and get 4.5. I admit I didn't think of DEF though. His truck no longer needs that so that would add more to the newer truck cost.

Your truck does very good on fuel. I have a friend who bought a new glider flat top 389 3406E cat that made 4.5 mpg pulling a van. When he went to flat bed his mpg shot up to 6.2.

I would like a nice newer truck that rode and drove nice and i've tried and tried to justify buying one, but I just can't. Too many red flags yet.

Just an example. That same Kenworth T680, ISX Cummins had a turbo go out. $6,000 just for the part. That does not include labor or down time. My turbo goes out? $800 and about an hour for me to replace it. I got tools in my truck and could change it on the shoulder I would just need the part. That alone sucks up any money he saved on fuel for the entire year.

 

There are good/bad points to both. The electronics, especially emissions sensors, on newer trucks can drive you to the nuthouse, but the modern conveniences on them are very nice.
If I could I would probably buy a nice older truck, (my company requires less than 7 years old, emissions working) with a Cummins, repair expenses are lower since there's no electronics to go bad, you can get good mileage if it's setup right and you drive it right. Be prepared for electrical gremlins, the older wiring isn't sealed as well as newer stuff. Corrosion will cause lighting issues, but won't shut you down.
It also depends on what your intended use is as well as where you're going to be working it. In New York probably Ca, and possibly others, you better not let a puff of black smoke escape the stacks!