Originally posted by AndyU:
Well, after thorough testing, towing, empty, highway, city, etc, my mileage went down with the Predator. Running empty, I lost about 1.5 mpg in city driving and about the same loss highway. Towing was about the same, maybe even a bit better, but it's hard to tell because of the affects of wind direction, rate of travel, etc which makes it hard to get a good baseline. The Predator caused my DIC to indicate my mileage went way up, but hand calculating my fuel usage revealed that in fact it went down. Very disappointing.

After restoring the factory program I averaged 19.5 mpg on a 550 mile trip last weekend (empty at 70 mph w/ cruise and a tail wind). I got 22 mpg on the last 100 miles (empty, no wind, 60-65 mpg w/out cruise) after refueling. I think that's pretty good.

The truck definitely gets better mpg w/out cruise on, letting the truck slow up a bit ascending hills and speed up a bit going down. Also, if I keep it at 65 or less my mpg is much better. Also no hard acceleration.

I only have 5000 miles. I'm very happy with this truck.
Quick update. I now have 15,000 trouble free miles on the truck. I added an Edge EZ and I run with synthetic oil. I can now get as high as 24 mpg if I can roll along at 55-60 without any stopping. The norm is more like 22 hwy and 18.5 city, subtract 1 mpg when running with winter blend fuel. The Edge EZ definately gave me at least 1 mpg better, maybe a bit more.