2023 Volvo VNL 860 MPGs Parameter Improvements?

Have a new Volvo VNL 860 with the D13 500HP 1850/1550 Eco Torque Engine 2.79 RAR. Have the P, E+, EE+ settings.

Trying to figure out if anyone has some good ideas on the Parameters to help in MPG's.
I pull a dry van 15-35K pretty much east or west coast from Midwest. Right now I have right at 40K and getting 8-8.5 MPG's most of the time. So I am not doing bad but always looking for improvement.

Most times I drive 62-67 depending on load time frames. My RPM's are 1150-1250 most of the time on cruise. I have the flow below set up on the truck. Trailer has skirt and adding a Rocketail to the back of the trailer in a few weeks when it comes in.

Feel free to comment on anything you do to get better MPG's. I am wanting to get in the 9's with this set up without slowing down more than 62 MPH.

 

No thanks. 55 is actually a bad number for me for my gears.

 

I bet you are heavy haul? If not ouch!

 

I have duals and I have synthetic from factory. Thought about getting them switched out to
Spicer® FE75W-90Fuel-EfficientSyntheticGearLubricant
Or whatever the newest is. Not sure how much it will help but looking at doing that after winter.