Way to get the best MPG out of my car?

[HasteTheMoment]

Hello, I make a 160 mile roundtrip every weekend, 80 miles back and forth. I want to know how to get the best mpg out of my 08 6sp versa. I usually haul and go around 80ish, but however when i cruise at 70 I see I get a little better mileage.

Any help on the best mpg cruise speed?thanks

[marlin29311]

You have to try it out and see what works best for your car - each car (and each version of each car) has its own little sweet spot. If you say that going 70 gets better mpg than 80, try going 70 instead. There is a point where the gas consumption outweights the increased speed, and 70 may very well be the point. I know on my altima it is about at that area - my car does it's best when the RPM's are below 2000...

[biggie]

Basically on the highway with the 6spd the slower the better. Due to the gear ration keeping the rpms so high it drinks gas when going over 60-65mph.

[#1Tango]

when im not in a hurry i cruise at 60mph. i get the best mpg that way. i hate driving that slow but i can't afford gas. the best i got out of a full tank was 440miles then my empty light turned on. i baby'd that tank like crazy

[Bubs daddy]

Slower, steady speeds will yield better mileage. Feather the accelerator pedal when starting from stop. Different gasoline formulas required by your state or area affect mileage. Going 80 mph will definitely use more gas than going 65. Going 55 will get better mileage than 65.

[DejaWiz]

Slower, steady speeds will yield better mileage. Feather the accelerator pedal when starting from stop. Different gasoline formulas required by your state or area affect mileage. Going 80 mph will definitely use more gas than going 65. Going 55 will get better mileage than 65.

Truth.

And on the gasoline formulation... don't use any kind of ethanol blend, even if it's a lower price. Ethanol will impair fuel mileage.

In my area, our midgrade gas (89 octane) has a 10% ethanol content and is $0.10-12 cheaper than the 87 octane rated gas.

Driving about 90% city:- My V gets about 23mpg average with the ethanol blend- When I use the 87 regular, my V will get 24-25mpg average.- Using 91 premium, my V will average 26mpg.

Right now, gas costs this in my area:89 midgrade: $2.7487 regular: $2.8491 premium: $2.99

I drive it about 775 miles every month, so:89 midgrade: $92.33/month87 regular: $89.84/month91 premium: $89.13/month

89 with ethanol may appear to be the cheapest solution at the pump each fillup, but over the entire 775 miles, it's the most expensive option.

89 mid: $1107.96/year87 reg: $1087.08/year91 prm: $1069.56/year

By using the most expensive fuel at the pump, I save $38.40 per year at these prices. That's just about a free month worth of auto insurance. The savings is even greater as gas prices increase ($85.07/year if gas was $1 more for each grade).

Anyway, if you use ethanol.... Stop it.

[marlin29311]

Slower, steady speeds will yield better mileage. Feather the accelerator pedal when starting from stop. Different gasoline formulas required by your state or area affect mileage. Going 80 mph will definitely use more gas than going 65. Going 55 will get better mileage than 65.

Not necessarily true. While going higher speeds to increase fuel consumption, each car has a "sweet spot" where the increase in speed is greater than the increase in consumption. Saying every car gets the best gas mileage at 55 is like saying that every tree is the same, or that a burger is the same at any place you get it. It's simply not true.

Driving about 90% city:- My V gets about 23mpg average with the ethanol blend- When I use the 87 regular, my V will get 24-25mpg average.- Using 91 premium, my V will average 26mpg.

That blows my mind too - using a higher octane than what the engine calls for doesn't do anything to help with efficency. Not saying you're not getting those gains, but theoretically it doesn't do anything.

[DejaWiz]

That blows my mind too - using a higher octane than what the engine calls for doesn't do anything to help with efficency. Not saying you're not getting those gains, but theoretically it doesn't do anything.

Exactly my thoughts on it, as well. I switched back and forth between 87 and 91, and the mpg were consistently observed to be around 24.5 and 26, respectively.

[superskunk]

24 in the city? i recently got 26 highway.... with my 20's on... yeah i know it sucks... but whatever... i need to put my 15's back on so i can get better mileage...

[Urq]

24 in the city? i recently got 26 highway.... with my 20's on... yeah i know it sucks... but whatever... i need to put my 15's back on so i can get better mileage...

You mean 20"s not 20's right?

[superskunk]

thank you speell check man! lol.... what would we do without you?lol.... but no i ment 20's, plural.... not feet...

[Bubs daddy]

Quote »Not necessarily true. While going higher speeds to increase fuel consumption, each car has a "sweet spot" where the increase in speed is greater than the increase in consumption. Saying every car gets the best gas mileage at 55 is like saying that every tree is the same, or that a burger is the same at any place you it. It's simply not true.

[/quote]Bulltucky.

I didn't say every car gets best mileage at 55 mph. I stated you'll get better mileage going 55 than 65.

Sweet spot? On what vehicle? Unless you're in neutral going downhill, the fact is, going 55 mph will give you better mileage than going 65.

Going 65 mph takes more fuel. Going 55 mph takes less fuel.

Your analogy doesn't make sense. Comparing burgers and trees is ludicrous. A Ford F150 will get better mileage going 55 than 65. As will a Honda Accord, a Chevrolet Corvette and a Toyota Corolla.

At a steady, constant speed, going 55 mph will get better mileage than going 65 mph. Going 65 mph will get better mileage than going 75 mph.

[marlin29311]

Bulltucky.

I didn't say every car gets best mileage at 55 mph. I stated you'll get better mileage going 55 than 65.

Sweet spot? On what vehicle? Unless you're in neutral going downhill, the fact is, going 55 mph will give you better mileage than going 65.

Going 65 mph takes more fuel. Going 55 mph takes less fuel.

Your analogy doesn't make sense. Comparing burgers and trees is ludicrous. A Ford F150 will get better mileage going 55 than 65. As will a Honda Accord, a Chevrolet Corvette and a Toyota Corolla.

At a steady, constant speed, going 55 mph will get better mileage than going 65 mph. Going 65 mph will get better mileage than going 75 mph.

...which is in essence saying that every car does it's best at 55. Does the car get better gas mileage at 45? Then 35?? Hell, I should just stop driving because that's my best gas mileage!

There is no way of proving every car gets better gas mileage at 55 over 65 without data. Going from 55 to 65 is a 18% increase in speed - can you prove that every car has an increase of fuel consuption of over 18%? How long of a drive are you talking about? The longer you are at a steady speed, the better you can realize economies of scale on your engine (aka efficency). There are way to many factors to make a blanket statement saying every car gets better gas mileage at 55 over 65.

I have an '08 altima coupe 3.5 and I get better gas mileage going 70 over 55. This is based on a steady 50 mile trip. Woops...there goes your theory. Each car has it's own speed that it reaches peak efficency. Stop believing the garbage the EPA trys to feed you.

[Bubs daddy]

Who stated anything about the EPA? I didn't.

You need to read what I wrote. Going 45 mph will get better mileage than going 55 but that's not what I was discussing.

The original poster's question regarded highway speeds so I was stating as such. You need to read what I wrote. I never stated in the above posts that mileage at 55 was better than 45 or the best mileage is solely at 55 mph.

It's simple. At a steady, constant speed, your engine is at a higher RPM and sucking in more air at 65 than 55, thus so it takes more fuel.

And because it's going 18% faster doesn't mean it burns 18% more fuel. I never said that. I said it uses MORE fuel, not an equal percentage related to the speed. Perhaps it uses 5% or 7% or 3% more fuel.

And your Altima does not use less fuel at 70 than 55. You're deluding yourself. Your car's engine is running faster and taking in more air so it needs more fuel. So unless you're comparing going 70 mph at 9000 feet above sea level and going 55 mph at 1000 feet, your Nissan gets better mileage at 55 than 70.

It will also get better mileage at 45 than 55. It will, however, get to a point of insignificant fuel savings at much lower speeds. Again, constant, steady speeds at the same elevation.
Modified by Bubs daddy at 1:15 AM 10/19/2008

[raventare]

And because it's going 18% faster doesn't mean it burns 18% more fuel. I never said that. I said it uses MORE fuel, not an equal percentage related to the speed. Perhaps it uses 5% or 7% or 3% more fuel.

Wow, so many people on the web like to talk about things they obviously never checked.

As was stated before, EVERY car/truck does NOT get better gas mileage at the lower speeds just because they are using less gas...they are also covering more miles going faster so the miles per gallon goes up. There is a sweet spot for each car/truck.

The best way to save gas is "draft" the car in front of you but watch your temperature gauge if you are going fast and please NO texting or talking on the phone...YMMV

[marleyfan]

I recently saw a consumer news segment that tested going 90kmh (56 mph) vs 110 kmh (68 mph). I think it was in a toyota but I can't recall. They used an onboard computer similar to the scanguage. They drove the same section of highway repeatedly under the same conditions and didn't start measuring until they had reached the target speed. They found that going 56mph used an amazing 30% more fuel than going 68 mhp. I realize that not all cars will get the same results but it was certainly a wakeup call for me. Perhaps someone with an unmodified Versa and a Scanguage could try it and let us know the results and put this argument to rest.

[marlin29311]

Who stated anything about the EPA? I didn't.

You need to read what I wrote. Going 45 mph will get better mileage than going 55 but that's not what I was discussing.

The original poster's question regarded highway speeds so I was stating as such. You need to read what I wrote. I never stated in the above posts that mileage at 55 was better than 45 or the best mileage is solely at 55 mph.

It's simple. At a steady, constant speed, your engine is at a higher RPM and sucking in more air at 65 than 55, thus so it takes more fuel.

And because it's going 18% faster doesn't mean it burns 18% more fuel. I never said that. I said it uses MORE fuel, not an equal percentage related to the speed. Perhaps it uses 5% or 7% or 3% more fuel.

And your Altima does not use less fuel at 70 than 55. You're deluding yourself. Your car's engine is running faster and taking in more air so it needs more fuel. So unless you're comparing going 70 mph at 9000 feet above sea level and going 55 mph at 1000 feet, your Nissan gets better mileage at 55 than 70.

It will also get better mileage at 45 than 55. It will, however, get to a point of insignificant fuel savings at much lower speeds. Again, constant, steady speeds at the same elevation.

Modified by Bubs daddy at 1:15 AM 10/19/2008

YOU need to read what I'm talking about - I'm glad you know the gas mileage I'm getting without driving my car buddy. Constant speed going 70 mph i get around 28.6 mpg. Constant speed at 55 gets me about 27.1 mpg.

Yea, your car does use more fuel at higher speeds - I never refuted that. However, there is a tradeoff. I'm going faster, meaning I am covering more ground in less time. The amount of extra fuel I have to burn does not outweight the gains in distance I realize from going at the faster speed.

You're crossing arguements.

And your Altima does not use less fuel at 70 than 55. You're deluding yourself. Your car's engine is running faster and taking in more air so it needs more fuel. So unless you're comparing going 70 mph at 9000 feet above sea level and going 55 mph at 1000 feet, your Nissan gets better mileage at 55 than 70.

In this statement, you say that I am using more fuel at 70 than at 55, to which I agree - I do use more fuel. However, you then elude to the fact that I get better mileage at 55, which is a completely different arguement, which is wrong - I get better overall mpg's going 70 versus 55.

The best way to save gas is "draft" the car in front of you but watch your temperature gauge if you are going fast and please NO texting or talking on the phone...YMMV

You have to be so close to the car in front of you to realize any true gains from drafting - this one is debateable.

I recently saw a consumer news segment that tested going 90kmh (56 mph) vs 110 kmh (68 mph). I think it was in a toyota but I can't recall. They used an onboard computer similar to the scanguage. They drove the same section of highway repeatedly under the same conditions and didn't start measuring until they had reached the target speed. They found that going 56mph used an amazing 30% more fuel than going 68 mhp. I realize that not all cars will get the same results but it was certainly a wakeup call for me. Perhaps someone with an unmodified Versa and a Scanguage could try it and let us know the results and put this argument to rest.

Thank you.

[boxcarbill]

The inadequate 6 speed wasn't designed for speeds over 60 mph. The government should mandate more fuel efficient automobiles if they are to be sold in the USA.I'd like to see a modification for the 6 speed transmission that would replace 5th gear with an additional 30% of overdrive over 6th gear. Then I could keep up with everybody on the freeway.

[marleyfan]

I recently saw a consumer news segment that tested going 90kmh (56 mph) vs 110 kmh (68 mph). I think it was in a toyota but I can't recall. They used an onboard computer similar to the scanguage. They drove the same section of highway repeatedly under the same conditions and didn't start measuring until they had reached the target speed. They found that going 56mph used an amazing 30% more fuel than going 68 mhp. I realize that not all cars will get the same results but it was certainly a wakeup call for me. Perhaps someone with an unmodified Versa and a Scanguage could try it and let us know the results and put this argument to rest.

Hmmm....first time I've quoted myself. Anyway...I inadvertently reversed the numbers. The finding was that going the faster speed used 30 percent more fuel.

[boxcarbill]

Hmmm....first time I've quoted myself. Anyway...I inadvertently reversed the numbers. The finding was that going the faster speed used 30 percent more fuel.

No sweat dood. The original didn't fly with anyone anyway.

[Bubs daddy]

Quote »YOU need to read what I'm talking about - I'm glad you know the gas mileage I'm getting without driving my car buddy. Constant speed going 70 mph i get around 28.6 mpg. Constant speed at 55 gets me about 27.1 mpg.

Yea, your car does use more fuel at higher speeds - I never refuted that. However, there is a tradeoff. I'm going faster, meaning I am covering more ground in less time. The amount of extra fuel I have to burn does not outweight the gains in distance I realize from going at the faster speed.

[/quote]And I'm telling you I don't have to drive your car to tell you that your measurements are wrong. You're going to get better mileage going 55 than 70 mph in your Altima.

I'm very aware that you cover more distance going 70 than 55 but that doesn't offset the significant increased fuel use. If you have two of your Altimas side by side with exactly one gallon of gas in them, the one doing 70 is eventually going to run out of gas and be passed on the side of the road by the one going 55.

If you're asking if I don't believe your mileage figures, well...no. I don't. There's nothing special about your Altima that will give it better mileage at 70 mph than 55 mph. You're miscalculating and are in error.

You're covering more ground but it's less efficient. We're not talking how much time it takes to get some where. We're talking miles per gallon. If your commute is 70 miles and you're going 70 mph, you'll get there in one hour. Going 55 mph will take you longer to get there. But you'll have used more fuel going 70 than 55.

So again, whether you're driving an eighteen wheeler, or a Dodge RAM pickup, a Winnebago RV, a Honda Fit, or a Nissan Altima, you'll get better mileage going 55 mph than 70 mph. It's a fact.
Modified by Bubs daddy at 10:59 PM 10/21/2008

[Bubs daddy]

Going faster will get you there faster but you're overall mileage will be better, in many cases, significantly better going 55 or 50 instead of 65 or 70.

Your Altima does nothing special. It gets worse mileage going 70 than 55. It's just a fact.

Read on..

Top 7 Fuel Saving Tips

Quote »#3 Watch Your Speed – when speed limits were raised from 55 mph to 65 (and even 70 in some states), drivers everywhere cheered. Motor-down and get there faster. But are we really better off? Life has not only speeded up, fuel is being sucked down faster too.

Plus, avoidance reaction time decreases significantly at these higher speeds. Hey, we know it’s not cool to go slow like Gramps – that can be dangerous as well - but it is smart to be aware of the fact that each mph affects your car’s fuel economy.

According to the Union of Concerned Scientists, “government data indicates that fuel economy can drop by 17% for modern vehicles that drive at 70 mph instead of 55 mph. Even at 65 mph, fuel economy can drop by nearly 10% compared to driving at 55 mph.” [/quote]http://alternativefuels.about....l.htm

--------------------

From EdmundsQuote »Test #2 Lower Speeds Saves Gas

Remember a thing called the speed limit? On most highways it is either 65 or 70 mph. How fast are the cars and trucks around you going? From 75 mph to 90 mph. These people are wasting a lot of gas for the chance to get there a little earlier. Factor in safety concerns and a speeding ticket once or twice a year and going fast is a costly proposition.

Method: This test was simple. For 50 miles we drove with the cruise control set at 65 mph. Then, for another 50-mile stretch we drove with cruise set at 75 mph. We repeated this test going in the opposite direction. It is amazing how obvious the difference in gas mileage was. Just think what would have happened if we had slowed down to 60 mph. The only problem is with impatient drivers behind you. [/quote]http://www.edmunds.com/advice/....html

There's dozens more. Just accept this fact and admit you're wrong.

[Bubs daddy]

Quote »In this statement, you say that I am using more fuel at 70 than at 55, to which I agree - I do use more fuel. However, you then elude to the fact that I get better mileage at 55, which is a completely different arguement, which is wrong - I get better overall mpg's going 70 versus 55.

[/quote]If you agree that you use more fuel at 70 than 55, how can you get better mileage at 70 than 55?

Then you just answered your own question. You use more fuel. It doesn't matter if you cover more ground, it's just for that time. Going 55 will cover the same ground. You're just be going faster and getting there faster. If you use more fuel going faster, than you get better mileage at 55 mph, right?

Again, if two Altimas have exactly one gallon of gas. Going 70 uses more fuel, right? So let's say it uses 20% more fuel going 70 than 55.

OK. So they start of and the one going 70 mph got 20 mpg. So it traveled 20 miles. It's ahead of the Altima going 55 but since the Altima going 55 gets 20% better mileage, it travels 25 miles. So the car that goes 55 mph gets 25 mpg, the one going 70 mph gets 20 mpg.

Doesn't matter that the first one covered more ground quickly, in the end, the other car going 55 went five more miles. Took a little longer but it got better mileage.

[marlin29311]

I'm just going to give you a giant and call it a day. It's obvious that you can't change someone's mind once it's already made up - there is no point in arguing anymore with you. There are so many more variables that go into determining gas mileage than simple fuel consumption and speed.

Why don't you try going into the G section and saying this? You'll probably walk away missing a few body parts with the extensive knowledge and testing they do to prove my point as well...

[Bubs daddy]

You can't change someone's mind if you're stating things that are patently false. You can bury your head in your hands all you want but it won't change the facts.

Quote »Yea, your car does use more fuel at higher speeds[/quote]You admitted your car uses more gas going faster. That's what you said. Then how can your car get better mileage going 70 mph than 55? You just contradicted yourself.

I'm stating facts. Because you don't believe it doesn't make it any less true.

The original poster asked for ideas to save gas. I gave him a few. I don't think it's right to mislead him by stating things that aren't true.

And why would I need to go into another area of the forum to state what has been known for years? There are people that belong to the flat earth society as well. Doesn't make the right. What do you think was one of the main reasons the federal government proposed a national speed limit of 55 mph in the 70's? To save fuel.

Out west here we enjoy 75 mph limits but we know we use more fuel when we do. That's the tradeoff, you get there faster but use more fuel. I like getting there faster so I don't mind using more fuel..

Ask a Nissan engineer if your Altima gets better mileage at 55 mph or 70 mph.

[marleyfan]

Constant speed going 70 mph i get around 28.6 mpg. Constant speed at 55 gets me about 27.1 mpg.

Just wondering how you got these figures. Cuz they contradict everything I have read on this subject. Did you do this under similar conditions and measure using a scanguage or similar obdII computer?

[marlin29311]

Just wondering how you got these figures. Cuz they contradict everything I have read on this subject. Did you do this under similar conditions and measure using a scanguage or similar obdII computer?

I get it from the computer readout built into the altima based on the same 40 mile patch of I-95 between NJ and philly. I go to philly a lot (graduated from school there) and I tested this out. No A/C either times, windows closed, fair temperatures, minimal traffic, if any. Almost constant speed (impossible to keep a constant speed with hills and such). I'd take pictures of the computer, but I don't take pictures while driving.

You admitted your car uses more gas going faster. That's what you said. Then how can your car get better mileage going 70 mph than 55? You just contradicted yourself.

I said that my car uses more gas - however, the increase in speed outweights the increased consumption in fuel, therefore giving me slightly better gas mileage. Once I start hitting 75 or so, it tops off and my mileage starts to go down.

Ask a Nissan engineer if your Altima gets better mileage at 55 mph or 70 mph.

I'm my own engineer - I do my own work, I read all the service manuals, and my Dad works for a company that helps build components for Nissan. I have a fairly high working knowledge of my car, and could easily attain my ASE certification if i needed to - I'd rather work in insurance though; pays much better.

And why would I need to go into another area of the forum to state what has been known for years? There are people that belong to the flat earth society as well. Doesn't make the right. What do you think was one of the main reasons the federal government proposed a national speed limit of 55 mph in the 70's? To save fuel.

Because they'll prove that you're wrong. Sure, some cars might fit this bill, but after all of the research that the guys over there do, they can also show that going higher speeds in certian instances gets you better miles per gallon.

[my_new_v]

I didnt really read through this thread a little. But in your user manuel, if you look up the mt part, it will tell you what the reccomended shift popints are (if its the same as all other manuels). And usually with a 6spd right around 65mph is the best on hwy use, after that your throwing away gas. If anyone has said anything that I have I am sorry lol.

[my_new_v]

I now did some reading.

I believe Bubs Daddy, there are facts/proof out there to prove what he is saying (not only the ones he posted, ive looked into it more)

And I believe marlin29311 is talking about time/fuel use. I can see what he is saying about the distance cover vs speed vs gas consumption.

I think we just had a misunderstanding?

[Shad0wXCalibur]

Wow. Going slower doesn't automatically mean better mileage. Each car has a cruising RPM where it's most efficient. My CVT gets better going faster than it does slower because the CVT has too low of an RPM at 55 or below and it lugs it down a little but once I go faster, it starts to get into the range where torque increases and carries the car more easily.