Hey Mike you plan on getting super singles? If I'm not mistaken they say tankers are one of the better types of equipment to use them with. Not sure why though.

Absoultely not.

You should buy this KW I'm drivin. The harder you pound on it, the better the mileage gets. I made a post on this same topic, and my results were a complete 180 from what I expected as far as fuel mileage.

My results are pretty much exactly what Mike said. 8/10ths of a US gallon getter mileage (average loaded and empty) by slowing from 67 to 60.

It seems I'm into the summer fuel now. Last tank was 6.7 mpg average (75,000 lbs loaded & 35,000 MT)

I've been running between 62 and 64 mph for three years now. There are cost savings that are harder to see in the short term, but well worth slowing down. Keep running slow and you will see a huge increase in tire life. I get 200k miles on my steers, 400k to 500k on drives. Your brakes will last virtually forever. It's hard to quantify, but one would also assume that wheel bearing life will also dramatically increase. In fact, just about every part on your tractor and trailer that spins and / or generates heat will see an increased service life.

Me too. I switched my tires to smaller diameter (low profile) to bring RPM up a bit so I can slow down and still have pulling power. I now almost always drive at 58 mph with CAT turning 1300. If I have a really heavy load and my route goes thru big hills, I increase the RPM to 1350 and then I'm doing 60 mph. I find 1300 to 1350 RPM is where my best fuel mileage is... 2004 CAT Acert C15, 500 hp at 1500 rpm, 1650 torque, 13 speed tranny, 3.73 rears, low profile tires (512 revs/mi).