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We have a 2004 F250 5.4 4x4 6speed 3.73 gears. Now we were wondering how many miles do'es it take for the motor to breakin? We took the truck on a trip yesterday and got 17MPG the truck now has 5500 miles on it.
What speed are you traveling? Do you have a truck bed cover? That's the best milage I've ever heard of. My best is 14.5 w/ the tail gate down, going about 75mph.
2004 F250 5.4L 6 speed manual
I have a tonneau cover on my '03 F250 SD CC 5.4L and I get 12.5 city, 12.5 highway and 12.5 combined and I do not push it. Count your blessings as you pass a gas station that I have to stop at......
I'm closing in on 3000 with my SD with the same drive train. I've noticed my daily driving average has gone from 13.7 first tank to 14.6 on the last. According to my local dealer's service mgr. about 5000 is considered broken in.
What speed are you traveling? Do you have a truck bed cover? That's the best milage I've ever heard of. My best is 14.5 w/ the tail gate down, going about 75mph.
2004 F250 5.4L 6 speed manual
While working as contractor at Ranger plant in NJ, Ford engineer told me tailgate up is better on SD's (about 7-12%) due to the aero and vacuum behind the cab thing..
I have a 99 sd f-250, 5.4. sc, auto, the engine was replaced by ford with a 2000 5.4
I drove on the highway with cruise control at 70 mph. my milage was 17.76 miles / am gal.
I broke in the new engine in several months before this trip. In the first 1000 miles, I never drove over 2000 rpm. I didn't care who was behind me, I was not going to rush it up to the speed limit!
I roughly fiquired that my fuel economy was approx one mph better than the 99 engine, perhaps
due to the slow breakin. right now in the winter in Ontario, half highway/city I get about 14 mph
american or 17 canadian gallon