Volvo D12 worse MPG

The big one is slow down - most but not all trucks will improve by 0.1 mpg by each mph you decrease.

 

For D12 55MPH is the best speed. Safey and good fuel milage

Also check boost lines, intercooler and EGR for leaks

 

Check intercooler for oil spots. If it is D12D turbine sucks oil a bit from cranckase and if there is crack on intercooler you will see oil spot

 

Block off the egr!!!!

 

Follow the link to what I did....


It's an experimental thing. My average fuel consumption is slowly raising & my power has increased greatly!

http://www.thetruckersreport.com/tr...s/133337-a-quest-for-better-fuel-mileage.html

 

I gotta '05. 200000 miles ago I unplugged EGR's , bought a flow trough muffler from pittsburg power, slowed down to 61. I also only fuel at pilot and loves, those are the only places tha I never find any water in my water separator and I also noticed
When I fuel at flying j, petro and especially TA that my hp goes down and fuel consumption goes up. I also use howe's injector cleaner proportionate to every tank. It makes the engine run really smooth with the increase of hp. Besides winter time my fuel cons. Went from: heavy loads 5.5 to 6.4 going west. Going to florida 6.8. Light loads same scenario from 6.1 to 6.9 and 6.5 to over 7

 

Give Illinois Dyno Center an try, I think they can flash the ECM for better fuel mileage.

http://illinoisdynocenter.org/Volvo_Trucks.html

 

check exhaust manifold, also when your mpg dropped have you noticed any whistling??