I dunno what type of diesel is in the Massey (it'* my step-dads baby), but when using it with the loader and bush hoggin it'* never strained. Must have something to do with the hydrostatic setup it has.
I think I win the oldest tractor award thats a '51 for 8N runs like a champ we use a backblade to flatten out the horse manure by the barn and to clean the driveweay in winter, we also have a mower that drags behind it, and i also pull trees out of the woods to clear my quad trails.
hmm...I think my toys would win the biggest size wise award right now....
And then my favorite "oldie"
1974 Oliver 1855 (I know not that old....I work with older....dad has a 55 Farmall 400....)
there is a guy down where I am from that does antique tractor pulls with one of those....lol we have several MM well motors...good motors....never die...two of them are well over 50 yrs old. and haven't had to have major work done on them...