I had a 5 star tune on my 02 V-10 Excursion towing a 35ft 9300lb TT. I gained .5 mpg towing, no other change other than the tune. And yes, despite the negative people, the shift programming for has in them is less than awful! 5 star did their homework and it shifts the way it should have from the beginning. It does give a bit more power, but that’s not why I got it. It never really held OD even in the slightest headwind. After it took a lot to get it to kick down into 3rd.
Best mod I did to the V-10 other than the 3.73-4.30 swap.
And for those wondering, sometimes lugging an engine (lower rpm) it will use more fuel than running it at a higher rpm which is more efficient. It’s a fine balance of speed, rpm, and load.
