I’ve have a Detroit in the rear 14 bolt of my ‘86 CUCV and a Trac loc up front in the 60 both factory installed. I’ve now put 40k+ miles on the truck since 2010 with 2 drastically different engine/trans/transfer combos.
The Detroit is heavy duty and mindless…no air compressors or lines, or wires to worry about, no clutches to fail, or special gear oil that you have to use, you don’t have to consider slowing down going into curves. I drive the truck normally and make no considerations for altering my driving behavior.
Now are these factors minimized because the vehicle weighs 5800lbs and is a long wheel base full size pickup? Maybe?
I’ve never had a Detroit in a 40 so I can’t speak to that.
If you’re really on a budget a good ole Lincoln Locker worked for me when I was a younger man and the funds were non-existent.