More recently I replaced the front driveshaft yoke seal in the transfer case. This seal is one of the low points in the transfer case and when it is leaking you lose most of the oil too. It turns out the seal is the same part number as the same seal in the M series 5 ton military trucks, so the seals are readily available. I also installed a speedy sleeve on the yolk. This cured the bad leak in the transfer case.
Since I got this truck it has been operating on a 5 gallon can of gasoline, which the big Herc sucks down pretty quickly. I can't even make it to the ethanol free gas station on that lol ! So it was imperative that I install a real fuel tank on it. The truck came with two rusty fuel tanks sitting on the bed that I thought were the original tanks, but unlike the original tanks they were two different lengths and also had no provision for a sending unit. However they were the identical diameter and were obviously fabricated to replace the originals. It also came with a set of straps and several sets of wooden cradles. I looked in both tanks with a borescope and the shorter tank had some nasty looking rust inside but the longer one looked salvageable. I had the outside of the tank sandblasted and put a coat of primer on it. Then I got a gallon of KBS Tank Sealer. I thoroughly cleaned the inside of the tank with KBS Kleen and a bucket full of bolts, and rolled the tank back and forth on a set of rails I built out of landscaping logs. After rinsing with water I let it dry thoroughly. The next day I etched the inside of the tank with KBS Rust Blast, rolling it as before, and again rinsed it with water and let it thoroughly dry. Finally on the 3rd day I applied the sealer, again rolling the tank to get full coverage, then drained out the excess. Once this is done you let the sealant cure for 4 days. I painted the outside of the tank with the same rusty looking paint I used on the tail lights.
The next problem was how to mount the tank as it originally mounted to the wrecker crane frame. I got some 1-1/2" square tubing to simulate the crane frame, bolted it across the truck's frame rails, and mounted the tank to it the same way it originally mounted. I calculated the capacity at 55 gallons, which should be plenty. So now the old red Federal is licensed, insured, and pretty much road worthy, at least for short trips.