Odd MPG drop for my 5.3

Jon A · December 31, 2013

Yessiree, ALL of us have most assuredly been buying gas containing ethanol. We just don't know when we have gotten E90 or E85 until we see the reduced mpg.

Bill, you are not making sense. No pump in the country will give you E85 or E90 without being clearly labeled. People who buy this do it on purpose and know they're doing it.

I think you may be talking about E10 instead of E90. Yes, one can assume pretty much all gas has up to 10% ethanol. That's a big difference from 85%.

rudapa · December 31, 2013

Bill, you are not making sense. No pump in the country will give you E85 or E90 without being clearly labeled. People who buy this do it on purpose and know they're doing it.

I think you may be talking about E10 instead of E90. Yes, one can assume pretty much all gas has up to 10% ethanol. That's a big difference from 85%.

Thanks - that's what I've been trying to get across without success.

BillWho · December 31, 2013

Bill, you are not making sense. No pump in the country will give you E85 or E90 without being clearly labeled. People who buy this do it on purpose and know they're doing it.

I think you may be talking about E10 instead of E90. Yes, one can assume pretty much all gas has up to 10% ethanol. That's a big difference from 85%.

Jon, you are correct. I was getting E15 crossed up with E85 in my brain. Thanks for pointing our my error.

Bill, you are not making sense. No pump in the country will give you E85 or E90 without being clearly labeled. People who buy this do it on purpose and know they're doing it.

I think you may be talking about E10 instead of E90. Yes, one can assume pretty much all gas has up to 10% ethanol. That's a big difference from 85%.

Jon, you are correct. I was getting E15 crossed up with E85 in my brain. Thanks for pointing out my error.

rudapa · December 31, 2013

Rudapa, my sincerest apologies! Thank you for correcting my error. It is E10 and E15 fuel that we traveling folks have been buying.

http://en.wikipedia.org/wiki/Common_ethanol_fuel_mixtures

This blows a hole in my earlier calculations, but still, in my road warrior travels on trips, I have seen sizable drops in mpg after re-fueling, so there is something about the fuel that is different and I always associated it with ethanol. The above link says that the energy loss with 10% ethanol is around 1% lower mpg so I am stumped now as to what else it could be when I am moving down I-95 in flat Florida and see a difference in mpg after re-fueling.

TimmyG · December 31, 2013

Gas state to state varys in what's added also. Also in ohio right now we are on "winter blend" and it will kill your mpg. I would assume each region has its own blends

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blckthree · January 1, 2014

I just took the truck on a road trip from Nebraska to Tennessee. First on a positive note there was only a slight hint of "shaking" at 75 to 80 MPH on a couple road surfaces. For the vast majority of the trip it ran smooth from 70 to 85 MPH. Now on the MPG thing.

I got good mileage IMO on the way down with the 1st leg of the trip giving me 19.6 avg (NE - MO) with speeds mostly running 75 to 80. I got 18.8 MPG running from Nashville to Harriman on I40 and I had the cruise set at 85 MPH. I thought that was really good especially considering a pretty good cross wind. Now for the funny part. I was averaging over 20 MPG running around Rockwood and Spring City, but then I filled up at the Rocky Top in Rockwood, TN and my mileage on the same roads I was averaging 20 MPG dropped to 17 MPG and I got crap mileage all the way home averaging 16.5 MPG running 75 to 85. I did have a lot of head winds running home, but this is an extreme drop. I'm not sure what the deal is????

You said the magic word.. "Head winds", that will kill your fuel economy. I made a trip last month to Iowa from Oklahoma, 30mph tail wind going up and got almost 23mpg at 80mph, same trip coming home had a 20 mph head wind, same roads, same speeds and was just short of 17 mpg.

Mike

rudapa · January 1, 2014

I agree with the head wind - my 2010 HATED a head wind for MPG. My mileage dropped 3 MPG as soon as I filled up driving mostly on Hwy 27 in Roane and Rhea Counties. Wind was not a factor and I was getting 20+ before that on the same roads.

Aaron1085 · January 1, 2014

Have 1000 miles on my Sierra and have bested average 15.5 on a recent 200 mile trip here in New England (different than the farm geography). That said....I've used 87 octane and then 1 tank of 93. I don't plan to ever use E85, however wonder if there is truth to "winter blend" , etc.

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SLESierra · January 1, 2014

I just wonder if the exhaust flap in the exhaust could stick affecting
the MPG as well. I know when it usually sticks it is closed but could it
stick partially affecting fuel economy?

LaserBlueZ71 · January 29, 2014

I can't believe anyone has said this yet...SLOW DOWN!

80..85 MPH? Are you serious? You expect fuel economy in a full size pickup truck, with a gas engine, at 80 - 85 MPH? Get your head examined.

Try driving at 60 - 65 MPH, that's where fuel economy is. It still blows my mind at how fast people drive on the highway and think it is acceptable. Not only is 80 - 85 MPH a complete waste of fuel, your reaction time at that speed is completely shot. You better hope you never jerk the wheel or hit a bad pothole at 85 MPH. What will you do if you blow a tire at 85 MPH? You won't do shit, because you won't have time to.

Oh, and don't question my experience on this topic, I was a long haul trucker hauling over dimensional freight throughout all of North America for 6 years. I hauled loads up to 150,000 pounds with over 1,000,000 miles of accident/ticket free experience, as an owner/operator.

Seriously people, slow down. Not only will you save fuel and wear, but you will be safer for yourself, your family in the vehicle with you, and every car that passes you that has a family in it too. Your not the only one out there, don't dare to ever take the safety of others in your hands.

pm26 · January 29, 2014

I just took the truck on a road trip from Nebraska to Tennessee. First on a positive note there was only a slight hint of "shaking" at 75 to 80 MPH on a couple road surfaces. For the vast majority of the trip it ran smooth from 70 to 85 MPH. Now on the MPG thing.

I got good mileage IMO on the way down with the 1st leg of the trip giving me 19.6 avg (NE - MO) with speeds mostly running 75 to 80. I got 18.8 MPG running from Nashville to Harriman on I40 and I had the cruise set at 85 MPH. I thought that was really good especially considering a pretty good cross wind. Now for the funny part. I was averaging over 20 MPG running around Rockwood and Spring City, but then I filled up at the Rocky Top in Rockwood, TN and my mileage on the same roads I was averaging 20 MPG dropped to 17 MPG and I got crap mileage all the way home averaging 16.5 MPG running 75 to 85. I did have a lot of head winds running home, but this is an extreme drop. I'm not sure what the deal is????

Shoe box aerodynamics.

crushNchowda · January 29, 2014

I just drove 180 miles from Portland, ME to my home in southern MA. I reset the tripometer and fueled at a highway service station so literally ALL highway on cruise mostly at 80 mph. I got 15.1mpg and filled up w/ 93 octane.

This is the worst I can remember. Truck turned 9000 miles on the odo and has just about 50% on the OLM.

What gives? Winter gas? I mean that's a little ridiculous, the last few weeks its been very cold and I've been letting it idle every morning and every afternoon to and from work, thought that was a big factor for the drop in mpg, but this was all highways, all cruise, and with the truck fully warmed up.

Horrendous.

crushNchowda · January 29, 2014

I can't believe anyone has said this yet...SLOW DOWN!

80..85 MPH? Are you serious? You expect fuel economy in a full size pickup truck, with a gas engine, at 80 - 85 MPH? Get your head examined.

Try driving at 60 - 65 MPH, that's where fuel economy is. It still blows my mind at how fast people drive on the highway and think it is acceptable. Not only is 80 - 85 MPH a complete waste of fuel, your reaction time at that speed is completely shot. You better hope you never jerk the wheel or hit a bad pothole at 85 MPH. What will you do if you blow a tire at 85 MPH? You won't do shit, because you won't have time to.

Oh, and don't question my experience on this topic, I was a long haul trucker hauling over dimensional freight throughout all of North America for 6 years. I hauled loads up to 150,000 pounds with over 1,000,000 miles of accident/ticket free experience, as an owner/operator.

Seriously people, slow down. Not only will you save fuel and wear, but you will be safer for yourself, your family in the vehicle with you, and every car that passes you that has a family in it too. Your not the only one out there, don't dare to ever take the safety of others in your hands.

I understand where you're coming from and even posted to a thread previously on this forum declaring that traveling over 85mph in these trucks is way too fast under any circumstances, but 80 is going along with traffic up in the northeast in many areas. Also, no offense to your prior occupation but if you think 80-85 is Unsafe in a 5800 lb truck equipped w/ ABS 4 wheel disc brakes, stability and traction control well then anything north of 45 is pure lunacy in a tractor trailer w/ 100,000 gross weight- I could stop, swerve, and evade anything from 80 that you'd plow into at 50 give the same distance, maneuvering room, and scenario- no argument. Also, lots of tractor trailers up here travel 75+ on the reg

kstruckcountry · January 29, 2014

15 is pretty good for doing 80, IMO.

LaserBlueZ71 · January 29, 2014

I understand where you're coming from and even posted to a thread previously on this forum declaring that traveling over 85mph in these trucks is way too fast under any circumstances, but 80 is going along with traffic up in the northeast in many areas. Also, no offense to your prior occupation but if you think 80-85 is Unsafe in a 5800 lb truck equipped w/ ABS 4 wheel disc brakes, stability and traction control well then anything north of 45 is pure lunacy in a tractor trailer w/ 100,000 gross weight- I could stop, swerve, and evade anything from 80 that you'd plow into at 50 give the same distance, maneuvering room, and scenario- no argument. Also, lots of tractor trailers up here travel 75+ on the reg

I understand your point of view, but that is nowhere near an apples to apples comparison.

Even a truck by itself with no trailer would not stop in the same distance as a passenger vehicle. It's sheer size and weight that totally change the equation. Trucks are not meant to conform to that kind of standard because it isn't possible.

Trains on the main lines do 60 MPH, but they can reach weights of 20,000 tons, or 40,000,000 pounds. Think of that for a second. 40 million pounds of steel, rolling at 60 MPH. It seems insane doesn't it? Yet we do it everyday. Those same trains still cross roads and have a potential to kill due to the size and weight.

I can't tell you how many people have taken their lives in their hands in front of my hood. It happened on an almost daily basis. I never worried about myself, I worried about others around me. When a minivan would pass and there are small children in the back, I would cringe and hope that van would not do something stupid like cut me off. Heck, I thought that with every vehicle that went by. The only thing that helps you as a truck driver is constant diligence and being smart, maintaining following distance and always trying to have a back-up plan in case the vehicles around you do decide to cause trouble.

Four years ago in Nebraska, I was rolling down I-80 doing 60 MPH. My dad (he is a truck driver still, going on 31 years) was following behind me. He yells over the CB that a motorcycle with 2 people on it is flying up the hammer lane (left lane) and coming up fast. I look in my mirror and see the motorcycle coming. Don't ask me why, but you know those gut feelings you get that are so strong, you know with 95% certainty that something, somehow, is going to happen? I felt uneasy and kicked off the cruise control and coasted. Well, that motorcycle passed me and immediately cut in front of me. He didn't make it more then 100 feet in front of my hood when his FRONT tire blew out on the bike. I thought he was a goner. The bike went left to right and back again about 10 times, he struggled to keep it from going down. I was hammering on the brakes from the moment I seen that tire go, but I was gaining on him fast. With about 4 seconds to go before I would have hit him, I made up my mind that I was going to put er in the ditch, and not hit this person. Right before I started to head for the ditch, he himself took the bike down into the ditch and crashed in the high grass. It was a good choice for them because the thick soft grass saved them most likely.

Now, that was not my fault. Had I hit those people, the Police would have blamed me because, well, the public hate truck drivers. Yet, I was driving completely legal and safe. They cut in front of me and literally almost caused their own deaths. Why should I, the professional driver, have to risk my life, or possible end my life, by taking the ditch, to save the life of someone who was at fault? This happens all too often. 4 wheelers or motorcycles make a bad decision that is totally their own fault, and a truck driver takes the ditch to avoid killing them, only to kill himself. Where is the justice in that?

I don't mean to rant guys, I just hope to get others to stop and think about this. All that matters is everyone gets home safe to waiting wives, husbands and kids. Those few extra minutes you lose by slowing down, is nothing compared to losing your life, or worse, your actions causing someone else to lose theirs.