Is this NORMAL on E350?? please any suggestion
 

Hi
here is what seems to be problem at least i think got a ford E350 2012 5.4 extended cab gas millage is very low 12 MPG highway my previous van with 750K was giving me 13.5 ! here is what i noticed and i'm wondering what could be the problem?? transmission shop and mechanic told me it's normal ! driving down the hill speed 70 mph rpm shows 2100 i shift it to natural rpm stays 2100 no change???!!! i tried the same thing with other vans rpm drop to 1300 or 1400 but on my van it stays the same what is wrong can any one help me or give me some idea?? thank you in advance

Is your van equipped with cruise control?

Hi yes it has cruise control,, it's 2012 E 350 extended cab whit 117k mile on it.
thank you

Don't know if the cruise is causing the RPMs to stay up there, just thing out loud.