New Lowboy advice

Not sure what you are asking in the first paragraph?
I own 2 KW's, both with Cat 3406E motors that were before the C-15 and C15 , and i have only had the first one 5 years or so, mostly Macks, 2 cummins and one detroit, if you go over to the 18 wheeler section you will find many threads on Cat C15 motors, or start a thread there.
I never liked the idea of a pony motor, and never had one because where i live it get s cold in the winter and lawn mower engines always seem to have issues in the cold, plus you already have a motor in the truck to run the pto which replaces the engine on a pony motor, less maintenance and more dependable with a wetline.

 

I have used a Honda pony (pump) motor nearly every day for the past 4 years and I work Saskatchewan,Alberta, Manitoba, North and South Dakota, Montana and Idaho.

If you service them regularly they will give good service for years.

 

You would know more about working in cold weather then me doing work in Canada!
Good to hear that it is working out for you.

 

Condition and how well it was maintained is just as or maybe more important then mileage.
My 1999 Kenworth w900L cat 3406E with 40k rears and 10 speed had approx. 500k miles on it when i purchased it over 5 yrs ago but was in very good to excellent condition and was bought from a dealer that was traded in from the original owner for a new truck.
My KW 1999 T800B that i purchased last year has a cat 3406E 46 rears, 13 speed thick single 3/8 frame with 54,000 miles ecm verified purchased privately in excellent condition but the gelcoat on the cab and frame was pealing.
the W900 needed a complete wetline, the T800 needed the wetline updated for my use, both trucks have been good, the T800 i just put on the road which i purcased last year but decided to strip the whole truck down to repaint.
Hawking the internet is the key to any purchase, also having a good mechanic that can be a second eye and have the software to check anything you might miss or overlook
Hope that helps