I own a Workhorse 8.1L and Allison
When you ask who makes the better engine, You may well start a religious debate, I have driven both cars by Ford, GM and Chrysler and in truth do not like Fords, This however does NOT extend to their truck engines, Their larger products are good. (like the V-10) just the smaller engines I do not like, oh there are a few other things. The ford engine is rated at a much higher RPM so the 8.1 L is in fact more powerful, with better low speed performance, This I like... Sadly.. Mine had a major problem.. Just what will have to wait for an engine-topsy to find out and that will take a couple years.
But still: I would rather drive a GM or Chrysler than a Ford (My towed is a Dodge).
But when you ask who makes the best transmission.. EVEN FORD says: ALLISON.
yup, Ford's latest improved transmission was advertised as "Ford's Answer to the Allison" which means even Ford says Allison is best.
And I have yet to find anyone who argues with Ford on that.. I also fully agree, my Allison has been fantastic.
What happened with my 8.1... usually I would use at most 1 QT of oil a year, and that only when I crossed mountains... Well, i left out of SC on June 24 I was down perhaps a cup (Having last filled in Michigan 800 miles north in November of the year before, I normally change in November) arrived where I am now on Jun 25, one month later I went to leave I got a low oil warning, Added 3 quarts and not very far later got another low oil warning, lost pressure, BOOM and the engine's blown.
How it went through that much oil in less than 300 miles I do not know.. But I'm guessing road hazard damage to filter or oil pan may have contributed since that is basically the only answer that makes sense.