Did I just get 16+mpg?

[Boone83K10]

my 1000 foot elevation change driving to work and back (if I do drive the truck) is killing my MPG.... at best I get 8 mpg and I drive like a grandma.

 

[austinado16]

Thought I'd give a mileage update since I finally got to tow the camper up to the mountains and back last weekend.

It's about 5hrs on the dot, each way, and 500mi. There are 2 long steep 1,200' grades on the freeway to get out to the CA Valley, and then a twisty 2 lane, 30mi long, approximately 7% grade climb from 300' to over 7,000' and then a twisty 2 lane 30mi drop to 3,500' and back up to 4,500' where we camp. Then reverse all that for the drive home. 95-105*F in both directions, 'cept back in the mountains. Max speed up the grades is about 40mph, if.

Needless to say, brutal haul, with the engine fan clutch engaged and trans temps topping out at 210-215*F during the steepest parts of the climbs.

Prior to leaving, I bumped the fuel pressure to 13.5. Rarely do I make it there and back on a tank of fuel, and if I do, the needle is buried on the empty line for the last 20mi and I'm sweating bullets. This time, the gauge is showing 3-4gallons, so rough guessing, that's somewhere in the high 16's, towing 2,500lbs of camper up and down 7% grades in the heat, and some of that was wasted driving around the campground for 30min in 1st gear, looking for the "perfect" camp site.

Crazy.

Unrelated not: Prior to leaving I switched to DOT5.1 brake fluid, but that's a story for another time.

 

[DoubleDingo]

That is excellent mileage for lugging that much payload around the mountains.

My '65 got 14-16 on the highway cruising at 70. It had 3:54 gearing. My '81, I took on a trip in February 2013 and using google maps, I logged every single point we drove to and from, and how much fuel was bought. It got a disappointing 8 mpg at an average 65 mph on the highway. But the '81 has 4:10 or 4:11 gearing, and the engine hadn't been opened up on the highway for who knows how long, and the carburetor was gummed up from sitting for long periods of time. Now I have switched to vortec heads and gm performance high rise intake, the tops of the cylinders were cleaned of all caked on carbon, new spark plugs for vortec engines, the cooling system was cleaned and is operating extremely efficient, and the carburetor hasn't been rebuilt but it is operating much better and more efficiently. I am planning to take the truck camping soon, and that will be a 4.5 hour trip (460+- miles) one way, with minimal payload. Hopefully the truck will get better mileage, but I doubt it with such low gearing.

 

[NOPHO84K30]

I just dumped 30 gal in 33 miles.. filled up 46 gal tank frickin hose clamp broke on the line. It was still connected but loose electric pump pushed it all out. Bye bye $100. Lucky didnt catch fire it was 105' today in phx