Opinions/what to look for, on this truck. 2012 Freightliner Cascadia.

2012 Freightliner Cascadia day cab, DD13 455hp, 10 speed, fleet owned/maintained.
3 or them for sale, 2 have 250k miles, one has 225k. Out of service/for sale since 2017.
Sale price is in Canadian money, recently discounted, exchange makes the price under $25k U.S.
Any known problems with Cascadia's, or the engine, of that year?
To be used to pull gas tanker.

 

OR...Would I be better off with a 2013 Mack Pinnacle, 263k, 505hp MP8, 10spd, for $29k?
Benefit of Mack would be close by dealer. Freightliner dealer is at least an hour drive.
I "think" the Mack is a better truck, yeah, I now it's a Volvo underneath.

 

If I had the choice, I would go with an older, pre emissions truck, but I don't. No less than 10 years old, all emissions equipment must be in working order.
Knowing that 400k or so is where emissions systems start needing cleaned or replaced, I'm thinking that a low mile truck will give me a couple years before I need to spend that money.

 

Yeah, I thought about that too. Also algae in the fuel tanks.
I think I'll pass on that one and keep looking. Not real crazy about Frtlnr anyway.

 

There are a lot of them for sale in the price range I'm looking. I found one with a 450hp Cummins ISX 337k, that looks promising. Penske has them with even less mileage.
Lots of Canadian trucks around 2012/2013 for some reason.

 

The reason I was asking was to find out known issues on particular trucks.