Like Chuck was saying, it will last longer than we expect, as long as prudence is taken while driving the car. I have seen folk with not much experience in Mopars or automotive mechanics,mind you, that just want two things: lots of power and a big engine. What they don't look into is that the rear differential plays an intrigal part in the whole system and often disregard it. For instance, I have seen individuals who have placed big blocks in A bodies and left the 7 1/4 in place. No breakage. Like said, its not a guarantee that anything will break or survive. It all depends on the conditions its subject to. I romp on my ride fairly hard at times and the diff never howls or vibrates and is visably spotless from the outside. I run premium oil in it and its well maintained. I also have a 76 Valiant with a slant and A-833 4speed. I bang the gears pretty hard sometimes to get it up to speed and ut holds up great. It has well over 300,000 miles on it and the motor was rebuilt with a hotter cam. I bet it holds up well, even behind the 500 horsepower motor that Adam has. Well, at least until the deadly thrashing begins.:snakeman: