2008 Mack granite gu713

[Diana1975]

Hi my issue is that my 2008 Mack shuts off on me as soon as it goes over 30 miles and hour ..what could be causing this issue ? I can run it all day at the speed of 30 but as soon as I take it up to about 35 it loses power and shuts off and my foot on the gas pedal is all the way down to the floor and it stays at that speed ... please help me I’m very frustrated thank you 

[Mackpro]

Power divider or axle inter lock engaged . Is the PTO light on the dash on or engaged . Both of these can limit road speed . Also if rear suspension is air , if air bags are down it can limit road speed as well 

[Diana1975]

Thank you for your response I also forgot to mention that it really has a hard time starting we have to put starting fluid to get it going ... and like I said when I take off to drive it it literally starts to sputter and lose power when I start to put it in 6 th gear and then it says fuel restriction active ..air restriction active ...and then it shuts off at about 35 we already cleaned out the fuel lines changed fuel filters and nothing changed .. 

[DoubleFrame]

I had a 2008 GU with the same issue, it ended up being the injectors and injector cups.