Big Trip, small smiles
 

Just finished a 5282 mile round trip to Yellowstone Nat'l Park, but am dissappointed in my mileage. I was hoping to finally break 40 mpg, but fell short. My Q5 ran perfectly with excellent comfort and road manners, and we were loaded and running heavy, but I was sure I could break the magic 40 mpg barrier. Kept the speeds generally below 75 (except during a Texas rain storm avoidance - quick sprint to 95), and drove like a "mature" adult that I am. No matter, the best I could do was 38 plus mpg. Had rain, winds, snow, tornado, traffic, mountain climbs (9114 ft), and all the other good stuff you find on a long trip (avg 500 miles per day)....... but no 40 mpg. Guess I'm a bad driver!
Any tips?
Tenderfoot

I'd say that's great MPG compared to what others are reporting here on Fuelly and what the EPA is estimating.

I like the idea of getting great MPG numbers, but especially on a road-trip, I'm not a fan of sacrificing comforts just to gain an extra 2MPG (in your case).

Drive 55 instead of 70 and you will hit 40mpg easy peasy. There is more than 2mpg to be gained by driving slower.

How many miles are you on now? Diesels seem to take longer to break in. Cruising speed in important, but so is consistency, try sticking to a set speed for long intervals. Assuming you had ac on too? That can use 5 to 10% also.

Also, congrats on hauling all your passengers + stuff at a reasonable FE...