what speed is most efficient on the interstate

It will depend on your gearing, weight and terrain. I would say that if you are thinking about fuel efficiency that 62-65 would be about right for most terrain. I usually travel about 60-65 mph, but my trucks are not governed. I could bury the speedometer, but don't due to fuel economy. At 65 mph you can get decent fuel mileage while having sufficient momentum to get up most hills without having to drop too many gears. If you are going much slower then you may need to drop another gear or two to get over some hills.

 

A big part of efficiency depends on the driver and how he/she handles the truck...

Most of the mega fleet bottom feeders are governed in the 65mph range give or take either way a couple mph..

 

My truck isn't governed either but I set the cruise to 68 since I operate mostly in western states with at least a 70mph Interstate speed limit. I find in my truck its the ideal balance between time and efficiency.

I used to operate over 70 mph but chose to slow it down to save fuel for the company (we are a small fleet that's more like a family). I'd rather lose a few mpg to idle time since its summer and I don't have an APU.

 

Like they said. Most modern diesels are most efficient at 1375-1400 rpms from my understanding of what I have read on the subject. Setting your gearing to run 63-69 mph at those rpm's should be the answer but terrain and operator action can change number dramatically.

Best fuel mileage is achieved by minimal use of the loud pedal

 

Efficiency in mpg or profiitability?


If profitability then if you have back to back continuous loads AND the highway could handle it safely (and YES some larger interstates CAN handle high speeds, save the "speed kills" schpeel for later) then i would say 80-85 mph would be most efficient.

Because this way you can cover the loads faster thus increasing revenue. More loads delivered per week =more revenue brought in. Increased revnue WILL outweigh the increased fuel consumption. If you go faster---100mph lets say, then the increased fuel consumption may not outweigh the faster delivery times.

 

OK how about the "couple of speeding tickets kills profitability" schpeel??

Couple of those 15-20 over sure puts a dent in the ol bottom huh?Then you can spend some more time trying to con your way out of them, or pay one of the leech ticket service people. Cost's money anyways they just specialize in keeping points off. Yep miles miles miles that's the answer to big profit

You don't work for CR England or Prime do ya?

Or the guy that can run for $1.54 a mile because he pays attention to one of the two biggest costs in trucking? What happens to all your miles when he makes every mile he turns profitable giving him a decided advantage over someone blindly disregarding operating costs?

Nah miles miles miles miles...................................

 

You're right---i meant if the highway could handle it meaning if the speed limit were 80-85.

 

Man! The speed vs profit debate. Here we go again. This should be as fun as it was the last time. The same 5 speed demons vs the same 5 slow pokes. Roll yer britches leg up it's gonna get deep in here.

 

Gotcha.

Still think fuel mileage is important and that drivers should base the costs on a per mile basis.

Someone spending $.50 mile on fuel has a distinct advantage over someone spending $.60 or $.66 (8 mls/gal as opposed to 7 or 6) when trying to bid loads or contracts. With shippers figuring their costs over millions of miles those ten to sixteen cents make a huge difference to them leading them to utilize the more efficient company.

Just an example but if:

Company A breakdown;

$.52 Employee (that's about $.40 cents to the driver with SS match, vacation, insurance, workers comp.....)
$.50 fuel
$.20 license and permitting
$.20 equipment(purchase and maintenance)
$.08 operations
$.08 profit

They could run for $1.58

Company B breakdown

$.52 Employee
$.60 fuel
$.20 license and permit
$.20 equipment
$.08 Operations
$.08 Profit

They run $1.68


Now your P+G you have roughly one million loaded miles a week that you need covered ( I would bet that's actually quite low) do you think VP in charge of shipping wants to pay $1,580,000 or $1,680,000? Betcha he could talk them into a $5,000 bonus for looking for the better price and still saving them $95,000.

Did you notice the unit for the new fuel mileage standards? Gals a ton per mile. This should be a clue into how seriously shippers are looking at what companies are doing to compete. Never that I have been able to find has fuel mileage standards been linked to how much freight is moved.

I understand the thought of more revenue means larger operating capital, however I believe every mile should be as profitable as the mile before it and the mile after it because the business model of deregulated transportation demands it. If your not doing it you competitors can starve you out.