What do you guys make of this post: "I love Diesel, If you want to clean a gear box(differential too) Drop all the oil, refill with Diesel fuel. Have the wheels off of the ground and run the truck in gear (high) for twenty minutes or so. Drain the gearbox completely and let drain overnight. refill with regular lube and run as/per usual. I also use this method to clean the inside of an OLD engine. Drain oil, change filter, fill crankcase with diesel (and 1qt of DextronII) Idle the engine for about 20+ min. DO NOT PLACE ENGINE UNDER ANY LOAD!! Drain crankcase,let stand with plug out overnight. change filter, refill with regular lube. Do another oil change after about 1000mi. Your engine will be clean as a whistle inside. I have successfully used these methods on older vehicles, and would definately do it to a newer diff, but probably not a newer engine." Never heard of anything like this before
I'm not recommending anything, but. . . Back when I worked at Sandy's Chevron, a pilot who brought in his Oldsmobile every month or two did the same thing: raise the car, drain the oil, lower the car, fill with kerosene, run in gear on the rack for X minutes, drain the kerosene, fill with oil. Car ran for about a bazillion miles, and the oil never got black.
