I have a ford manual with spicer transmissions and PTO's in it.
It shows what is called a "power divider" used to take one PTO shaft and run multiple things, like two winches or hydraulic pumps.

Also shows a "split shaft PTO". This mounts in place of the drive shaft carrier bearing and offers a pto at full engine power while the final driveshaft is disconnected. Says for use with things like air compressors, pumps, and blowers.

It could be that the truck you are talking about used a "power divider" sort of like a transfer case that was intended for operating a second rear axle. But in place of the extra axle is the hydraulic pump. I think some of these could be shifted such that the driveshaft is out of gear and the second output, now for the hydraulic pump, in gear.

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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