I need better fuel mileage?

-have a semi- 2003 freightliner columbia condo 430 60 series detroit, 10 speed direct ex wal-mart.

would like more than 6.2 average miles to the gallon. any advice ?Depends a lot on your usage too. Keep up with maintenance, blow off the air filter at least once a month, replace when needed. Alignment is critical to avoid unneeded friction. Tire pressure for proper load bearing avoids friction also, try 105 steer, 100 others if you aren't there.



Driving habits are the other thing. Look far down the road to anticipate what is coming and plan. Don't run up to red lights or slow downs, coast in. Long, slow smooth acceleration is better than gunning up the rpm, and most of all, avoid idling. While unloading on pretty days, set your fold out lawn chair in the shade and read a book. Park facing the east in cold weather, the morning sun will help warm the truck instead of cranking it, park facing east in summer so the interior cools off quicker. After pulling up after fueling, kill it again just in case you bump into a friend or get stuck in line.



You have a Freightshaker and need a key to lock the door. The rest of us need a lanyard with a spare key around our necks.
Regular servicing, Make sure wheels are aligned etc, Drive sensibly. Inflate tires to the right PSI, Dont accelerate and brake harshly, Try to predict the road ahead. With sensible driving, I.e. trying to predict the road ahead and careful maintenance of the car it should improce. But not by much, Youre better going for a small engine diesel.
You might want to upgrade to a 2006 or 2007 model. My 2007 gets 6.3 mpg when going downhill. The fuel savings is incredible. And, if you can find one with a Cummings, all the better.