Parasitic draw & Pennsylvania cold weather might deplete batteries over a month ,enough to prevent cranking ,but probaly a good idea to have them load tested where purchased to see if ok or defective . Need to be charged right up to test.
On axle ratios fwiw,according to the manual, a 97 6.5 3500 with 410,s has about the same towing capacity as a 3500HD with a 4.63, rear end ---8000 lbs to 8500lbs in either case (same trucks good for 12500 lbs equipped with 7.4 engines} .
I kind of rationalized it as being due the sharp...
Maybe pump is positioned ( retarded )enough that stepper cant travel ( advance) enough to adjust for real cold temps .Maybe maybe maybe .
No disagreement on the need for a time check. My pump was changed awhile back & the way truck starts now (not as clean & more time on starter) makes me...
Still wondering about possible problem with ect sensor not giving correct info to pcm in very cold conditions & not calling for advance & high idle.
Would only take a second to unhook sensor to get pcm to default to -40 & see what happens.(on a cold Peace River day). Could check to see if...
There was a memorable phrase in Cowracers writeup where he was describing starting up the truck with the intakes off to check for leaks after replacing the pump .
It went something like "the 6.5 will start quite happily with the intakes off but you need balls of steel to do it".
If...
More after thoughts
Nice to have things : Lap top to maintain contact with 6.5 family , Dvd player & movies for passengers.
Log book & some way to remember to use it.