diesel fuel in Florida

[davisenvy]

I live in the mountains of NC. When I travel to Florida my tank will last me just past the Florida line. After I fill up I immediately lose almost 2mpg. This happens no matter where I fill up or what I'm towing. The mpg's don't gradually drop off, it is almost immediately after filling up with FL diesel and my mpg's don't come back until I fill up in GA or NC. Is there something I'm missing?

[Airstreamer67]

I don't notice any difference in mileage.

I got the same mileage to and from Key West to the state line as I got in other states.

So it doesn't affect me.

[thomasmnile]

Water-Bug wrote:
It has nothing to do with fuel. When you arrive in Florida, you get stuck behind senior citizens that are driving 20 mph under the limit. This puts your engine outside it's peak operating efficiency. When you finally get out from behind the senior, you instinctively nail it out of frustration, striking another blow at fuel economy. 🙂

This may be the most accurate explanation yet, but you forgot to mention the hard acceleration to escape the morons tailgating you traveling 30 mph or more over the posted limit on the interstates. :B

[RVBlade]

davisenvy wrote:
I live in the mountains of NC. When I travel to Florida my tank will last me just past the Florida line. After I fill up I immediately lose almost 2mpg. This happens no matter where I fill up or what I'm towing. The mpg's don't gradually drop off, it is almost immediately after filling up with FL diesel and my mpg's don't come back until I fill up in GA or NC. Is there something I'm missing?

I don't think it has anything to do with the diesel itself. I've talked about this very thing in a couple of other threads. I've experienced much of the same thing, although not as drastic as your mileage difference.

I can watch the lie-o-meter consistently work down as soon as I cross into Florida.

I think it has everything to do with the thick, humid air down here. There's humidity in a lot of states, but if somebody has never experienced working outside in Florida in June, July, and August, they just can't relate. The thick air causes more drag on the rig and the engine just doesn't run as efficiently.

I don't know the science behind it, but I do know that I get significantly better mileage pulling my rig up and down the hills in Georgia and Tennessee than I do in Florida.

[trop-a-cal]

If you think we have it bad with Diesel fuel at 15 PPM ULS Europe is at 10PPM ULS. There may be some 10 PPM sold in US, as we export Diesel to Europe at their required 10 PPM. That export income and world market prices cause the US to pay more for Diesel here than it would if we did not export for the big bucks Europe pays. Remember all those pre 2002 engines set up for LSD get worse MPG than the new design for ULSD.

[Dog_Folks]

Water-Bug wrote:
It has nothing to do with fuel. When you arrive in Florida, you get stuck behind senior citizens that are driving 20 mph under the limit. This puts your engine outside it's peak operating efficiency. When you finally get out from behind the senior, you instinctively nail it out of frustration, striking another blow at fuel economy. 🙂

So you were the one that blew by me in a no passing zone, and gave me a one finger salute, all because I was 3 miles an hour under the speed limit! :B:B:B

The absolute best towing mileage we ever got was in Denver.

It was up 3 MPG from normal in that thin air.

[Twain]

May or may not apply, but the best mileage I ever had out of two gas vehicles was crossing New Mexico on I-40. The high elevation, 5k-6.5k ft, does drop power, but the thin air is also easier to push through. I had an easy 10% mpg gain at those altitudes.
So maybe the denser, sea level air plays a role.

[davisenvy]

Well, if you were riding with me you'd see it. I saw it all day yesterday and today.

[LarryJM]

dalejiw25 wrote:
Your mileage suffers because air density decreases as altitude increases, But your cylinder volume stays constant. This means you're able to draw less volume (fewer molecules of oxygen) into the cylinders, the effective compression drops and the ECU compensates by reducing the amount of fuel added (to keep the mix proper)therefore using less fuel and less energy at higher elevations.

That's not the way modern diesels work and especially the turbo charged ones. The normal fuel air mixture concepts in gas naturally asperated engines don't apply to modern turbo charged diesels.

For the OP I can't see a 2mpg delta, but some Fl. stations are selling B10 which IIRC will give you slighly less mpg, but that should equate to less than 1 mpg non towing.

Larry

[Passin_Thru]

The cetane rating is lower in FL as they don't have winter blend nor do they care what the rating is as long as it burns. I never buy FL, WV or KY fuel if I can help it. If there were more water, the air would be denser, making you ahve more not less power. That's why a gasoline powered airplane is only good to about 18,000 ft without a turbocharger. Air is too thin and dry. Same with flying from FL to Flagstaff AZ. Low moist air, engines run better, prop grabs more air to dry high air. Look up density altiude.
NY fuel is 29 cents higher than other states so should have a higher cetane rating. It was 3.99 in Cortland yesterday and 3.70 in Fredericksburg Va.

[mudfuel07]

Water-Bug wrote:
It has nothing to do with fuel. When you arrive in Florida, you get stuck behind senior citizens that are driving 20 mph under the limit. This puts your engine outside it's peak operating efficiency. When you finally get out from behind the senior, you instinctively nail it out of frustration, striking another blow at fuel economy. 🙂

x2!!! I haven't noticed the mpg drop, but then again I haven't ever bought diesel in any place other than Florida. In about a month, I'll be buying fuel in Georgia, so I can test your theory.

[Water-Bug]

It has nothing to do with fuel. When you arrive in Florida, you get stuck behind senior citizens that are driving 20 mph under the limit. This puts your engine outside it's peak operating efficiency. When you finally get out from behind the senior, you instinctively nail it out of frustration, striking another blow at fuel economy. 🙂

[trop-a-cal]

Probably more water in the fuel in FL as the water tables and condensation factor is high. There also is in most instances a wind out of the South that drop all high profile vehicles on the way in unless you come in on a cold front that's headed South. I would also buy the diesel at a truck stop as the old fuel at some low volume sites probably gets degraded. Then the cold air tends to help in NC as it gets so hot in FL the air is wet coming into the intake and mixing with the Diesel. Moisture and rain plug many filters to the point of saturation cutting off air intake. When it's cold in FL engines seem to have more power.

[davisenvy]

Down hill from NC to FL, west wind, and the ambient temp was actually warmer in NC.

[AYRTIME]

You're going down hill from NC to sea level in Florida? On the way home you are headed up hill and likely into a N wind? Air temp will have some bearing as well, on tire press, oil temps and engine combustion.

And has been said different fuel blends.
Winter grade diesel here in On drops the mileage.