If your engine is healthy and you have fairly good aerodynamics, then the 0.1 mpg increase per one mph decrease is ballpark. If you're getting better fuel economy at higher speeds, you have a mechanical problem... a leaking charge air cooling system is a good place to look first.
I fixed my charge air cooler leak with a high temp silicone once. I gained around 1 mpg on average. Silicone will adjust to the expansion and contraction of the metal when it gets hot and cold, unlike a substance with a hardener in it. Some people spend the money and buy another air cooler.
I cant agree each truck varies I am in a rented T700 that gets worse mileage then my T700. Rented truck is goverened at 65 mine is 68 i run it 65-66 and would have avged 7.1-7.3 on this load . Rented truck never was over 6.6
only thing i seen make a difference in mpg is empty vs. loaded. i get .2 better empty. now take the trailer out of the equation and the t600 jumps up 3 mpg. i get 1400 miles per tank. going to boston to bring back a trailer. i got 2600 miles. made the entire trip on one tank. coming back with the trailer i got close to `1600 miles per tank.
What is the MPG prime wants you to have? REF side! im sure there is a diff in the REF and Flatbed Tanker side!
Depends on the specs of that rented truck TP... is it a Ryder? They have horrible specs, and in a OTR application will get piss poor mileage. I can see as much as 1.5 mpg difference between mid 50's and my 65 mph top end. We swap out trailers a lot, but a large portion of that variation is just slowing down. Its physics: The force produced by aerodynamic drag alone varies by the truck's velocity squared. That's huge. You have to overcome that force by feeding the engine more fuel. No clue. I'm a lease op, and my motivation for better mileage is more dead presidents in my pocket. You'll have to ask the company guys what they want these days. I ran on the company side for three years, and after they instituted the minimum fuel mileage requirement I never had problems meeting it. Quite a bit of it is technique... guys who have a problem usually have a bad case of lead foot.
LOL Snowy i bet your running a cat!!!!! lmao. It takes a lot of change on the drivers part to get high MPGs. Shifting at lower RPMs and not putting your foot to the floor between shifts, just ease it up. Those cheap tires you buy can hurt MPGs. Rolling resistance in the 140s and 150s. When a little more money can buy you a tire that has a lower rolling resistance, 95 to 110. That alone will save you almost .3 to .5 MPGs per gallon. On top of that these tires get more miles per 32cnds of tread which makes the tire far more cheaper than the retread or what ever cheap tire that u think your buying. Secondly when riding highway, if you find yourself braking and throttling to go around vehicles in yur lane, then you need to adjust to a slower speed. Less stress, braking, and throttling up. All fuel guzzlers. Find out where your engines sweet spot is, like mine is 1350rs. Anytime you go over that sweet spot your not gaining nothing. I rarely drift over 1500rs. Bottom line the more fuel mileage you can pull out of your vehicle, the less you have to run for more profit. Oh I almost forgot, I like those individuals running around with those 6" straight pipes running their jakes in truckstops, bobtailing, and just to be cool. Jakes use fuel as well. Use them when you need too, long downhill grades loaded. If you drive defensively, you'll come off the throttle in plenty of time to slow down to avoid braking. Some maintenance can meen the world in fuel economy, alignment, top tune, just changing your fuel filter more often. Again it could mean the difference between 6.3 and 7.5. Do the math on a 2500 mile week. Say your getting 2.00/m gross and fuel at $4/gal. So the extra maybe 30" to 45" is worth how much for the week????? This one crackes me up big time. Identical trucks and I take home almost $250 more than the other and he's doing 350 miles more than me a week with a higher maintenance bill. LOL Do the math. This ones a no brainer.
i get 5.5 - 6 empty with my 2006 volvo(cummins 450) ~ 5 loaded.took it to dealer last week.tune up didn't help.anyone knows what could be the problem? my mpg is just killing me
Each truck is different. The engine, transmission and the rears all play a factor, as does the weight of the truck and how often one runs heavy vs light. Speed is only one factor, and depending on other factors, a slightly higher speed would be better.
