Newbie member here, but will throw a recent flat tow into the mix. You guys with much more moxie than I on the subject can determine if what I experienced is the norm, or was it a operator (me) malfunction?
After action report for flat towing of the 85 K-5 Jimmy.
Towed the Jimmy (4 speed. 700 R-4 auto tranny) 250 miles up to Arizona high country behind motor home. Front manual hubs locked out, 700 R-4 tranny in neutral, 208 NP manual transfer case in neutral, key in first notch to allow steering wheel freedom of movement.
Towed for ten miles and checked, all appeared OK, checked again at 100 miles and found transfer case very warm & vent line was burping small amount of fluid. Checked again at 150 miles and found the transfer very hot, (sizzled saliva when spat upon) also by this time, it was really blowing tranny fluid (what it uses) out the transfer case vent line.
I proceeded to drop the rear drive line, continued trip with no other problems. reinstalled rear drive line on arrival and all seemed fine. Drove a couple hundred miles HWY and (very) rough back roads & 4x4 trails with no adverse effects noticed.
Dropped rear drive line, trip back home was uneventful as to towing. Now using Jimmy for local driving and have noticed no problems, so apparently no permanent damage occurred.
Have no idea as to problem unless the transfer case components do not take well to becoming driven, instead of drivers. The 208 NP transfer case does have an oil pump, so maybe it did not perform as intended. The thing is, there is no cooling of transfer case fluid under normal driving conditions, so what really gives, I have no real idea?
One thing I did noticed that seemed odd, with the transfer case in neutral, no input is induced into the R-4 tranny, (it stayed cool as the proverbial cucumber) but, the front drive shaft rotated when Jimmy was under tow and rear drive line was bolted up. (was locked in solid with rear drive line and couldn't rotate by hand, versus when in 2 wheel drive high, the front drive line does not turn when driving, but can be freely rotated by hand)
Any constructive input would be appreciated for enlightenment.