1800-2400 seems to be the sweet spot for power vs. egts with these engines. Above or below that my egts get really high when towing and pulling hard.

 

Do a little experimenting while pulling. Different engines are more efficient at different RPMs. I get better mileage at 62 (1900 rpm) than 55 (1600 rpm)mph. At 2000 rpm it goes back down. Also, TTs get worse mileage than 5ers, so don't get depressed when you do the math at your first fill-up and see that you only got 11 mpg. (your results might vary)

 

GAmes,

Thanks for the information, I planned on 11mpg, anything better I will be good. I get 18.5 city now and 21.4 on highway empty. I will post results next wek when retun from trip.

 

I am about the same. What rpm have you found empty?

 

Below 2k and egt's @600. Empty

 

A lot of good advice here... just to help emphasize the point, watch the gauges! They will tell you where you need to be. Do not lug the engine. If it is lugging and you see egts going up, drop down a gear and let it rev! You won't hurt anything but some fuel mileage. When on flat land and little resistance, no problem towing in OD either. Then your mileage will go up a little. Just learn to get a feel what your truck likes and your gauges will tell the story then drive it accordingly.

On the water, I think about the trip ahead and that will determine what I do. If it is a shorter trip and know I am going where the water is good... I only leave about 1/4 tank in. (Always have some water in there for the reasons mentioned in the above posts) If a longer trip (more potty stops) or going where the water is poor or non-existant, I'll fill the tank. Try to always have the gray/black water tanks empty (or as much as is practical) before traveling.

 

I will know on Wed when I pick up and head to Bruceton Mills WV, will be at night so I will really be able to see pulling through the hills. Hopefully I will really hear the turbo under load and test the boost gage.

 

Best mileage on my 12 valve is 2000 to 2100 rpm (65 to 68 mph). That usually gives me 19 to 20 mpg. 2200 (about 70 mph) drops me down to 18.