I put a TrueTrac in my '75 Ford half ton, it worked pretty well. At first. But it did not hold up to even an unloaded half ton. Had "pretty good" power from the built 390, and fat 35's, but I blew 2 of them out. Woulda been money ahead to put an ARB in from the get go, after replacing the Truetrac twice. Now the truck is my toy and it's fully welded. . I would not but a TrueTrac in a 3/4 ton with a Cummins, especially not in the rear. Maybe the ones in the bigger axles are stronger, but personally I wouldn't spend money on it.