Bad Gas Mile on Ecodiesel after dealer ECU update

[AncientApe]

I have a 2020 Ecodiesel, and it was in the dealers getting the 4x4 actuator fixed. After they were done, i noticed that trucked must have been flashed or modified because the remote lock was different. Before it used to lock and honk a split second afterwards. Now I noticed it honks and locks at exactly the same time. I didn't think much of it until I started noticing I got about 2 mpg loss in fuel economy. I drive pretty consistently and I've had very consistent gas mileage for the last 4 years. And then over the last month its different. Other than this and cracked glow plugs, the truck is fine. Any thoughts or help in this area?
Thanks for the help.

 

[busa2009]

did you verify that they updated it and updated to what exactly?

 

[Andymax]

Get a tune from Green Diesel Engineering in Michigan. Expensive, but well worth it. And don't allow the dealer to do any more software updates!