01 F550 4x4

[armyguy]

So we just got a new to us wrecker. Its a 550 auto 4x4. it has 276k on it. Its been getting about 9.3 mpg average. The truck is running all the time though and the idle kicks up to 1200 rpm when the pto it turned on. Its an electronice engine mounted pto. I was wondering what these trucks should get for mpg? Not sure what gears we have in it but at 65mph the thing is right at 2500 rpm.. I dont really want more power but if there is anything we can do to get better mpg that would be great. As much as we drive a 1-2 mpg would be great especially since the tank is only 19 gallons because of the wrecker body... Thanks for the help in advance..

[JSchuricht]

You need to drive slower, 2000 RPM is the sweet spot for MPG. Unfortunately with a 550, you have really low gears so your sweet spot for MPG will be something like 45-50 MPH.

[Zaairman]

It has 4.88 gears and is probably pushing 11k lbs with the body on it... What do you expect?

[armyguy]

yeah I cant go 45 mph...

Its closer to 13k with the body, but our other truck is the same truck and its a 6.0, Its deleted and running a mild tune and if I keep it at 65 its will get anywhere from 12-13 mpg depending on how cold it is.. I was really hoping I would get about the same as the 6.0 as far as mpgs... Im really thinking about regearing it... For what we use the truck for it doesnt need the 4.88 rears..

[Dave]

Thats average for a 7.3 550. Remember the 6.0s got another gear in the trans