SUV gas mileage - Feel free to participate

highender

stillen reports that the amount of leaching of horsepower is less than the amount produced....meaning less throttle pressure is needed for the burb to go....

they claim there is a 1 to 2 mpg improvement over stock ...

ateixeira

Interesting...but that's still the claim made by the person selling it. Of course it's optimistic.

-juice

blueiedgod

I was always of the opinion that the tin can vortex generators being hawked on the web and ebay were snake oil.

But recently, I had opportunity to view the injection manifold of a Corvette Cross-fire fuel injection system. Guess what - vortex generators built right in by GM.

So the million dollar question. Is there any value in them? GM apparently felt so since they included it in their vehicle design.

Any ideas or comments

Paul P.

Hond ahas been building Vortex funnels in the combustion chamber since its 1972 CVCC design. CVCC created swirl in the combustion chamber by opening one of intake valves later. This was 12 valve design, then in the 80's Honda developed the 16 valve engine which created more swirl and better economy by allowing more stratified charge. So, yes Vortex generation works, but it has to be done properly. I doubt having vortex on the intake will have any positive effect when the fuel air mixture is stitting still in the intake header waiting for the valves to open. It will probably improve fuel efficinecy of cabeurated vehicles, by making the mixture more uniform, but the swirl needs to be created in the combustion chamber for it to be effective.

P.S. I just got a CR-V with 5 spd manual, my first tank of City driving was 22 mpg.

Kirstie_H

A reporter with a national newspaper would like to speak with current SUV owners who previously owned a more fuel efficient car. Did they buy the SUV several years ago when SUV gas mileage wasn’t a big concern? With the high gas prices now, are they rethinking their SUV ownership? Are they considering trading in or selling their SUV for a more fuel efficient vehicle? If you fit what the reporter is looking for, please email Kirsten Holguin at kholguin@edmunds.com by May 27, 2005.

chitowncrvownr

Just filled up my new LX for the first time since taking delivery...got 27 mpg city/highway (first 277 miles). I can't wait till it's broken in! Anyone else have such good luck with these????

~Rob

blueiedgod

Just filled up my new LX for the first time since taking delivery...got 27 mpg city/highway (first 277 miles). I can't wait till it's broken in! Anyone else have such good luck with these????

I have a 2005 Honda CR-V EX manual, first tank was 22 mpg with 95% city driving. Second tank was 24 mpg with 80% City driving. I am not babying it. Do 12-15 mph above speed limit on highway, rapid acceleration in the city. I do cruise in traffic though. I am just establishing baseline for the acetone additive test that I am planning on running once she is broken in.

tytnsfan1

I get 12.5 miles per gallon driving mixed with stop/go traffic morning and afternoon. Really sucks!

stevedebi

Your car is 8 years old, why not buy a more fuel efficient one?

stever

Your car is 8 years old, why not buy a more fuel efficient one?

One car payment will buy a lot of gas!

Steve, Host

dw438

In combined city/slow rural/damn fast highway mileage, just squeezed 501 miles out of a 15 gallon tank on my Escape Hybrid. That's about 33 MPG. Not bad.
And, yeah, the truck was doing 80 on the L-I-E.

blueiedgod

In combined city/slow rural/damn fast highway mileage, just squeezed 501 miles out of a 15 gallon tank on my Escape Hybrid. That's about 33 MPG. Not bad.

That is impressive, but the correct way to calculate fuel efficiency is:

1) Fill up until the pump shuts off. Don't top off.
2) Reset trip odometer or record current mileage
3) Drive until empty or near empty (more empty is more accurate)
4) Go back to the same station, same pump, same time of day and climatic conditions.
5) Fill up until the pump shuts off, Don't top off.
6) Take the mielage driven and divide by the gallons you just bought = mpg

Just because you have a 15 gallon tank and you did 501 miles until the light came on means nothing, there is a gallon or two in the tank when the light comes on.

And, yeah, the truck was doing 80 on the L-I-E.

The only time one can do 80 mph on LIE is after midnight and there is no construction. LIE is the world's longest parking lot. Unless you meant 80 inches per hour, then I would believe you.

dsr9

I get about 17 City, 23 Highway, and average about 20 with mixed use,
which is pretty good considering the sticker rates it at 16/22. I don't floor
it very often, but do live on top of a steep hill. Also A/C was only used
on the freeway and only about 1/2 the time due to cool weather.

mbuchana

I've checked three tankfulls so far in my 2005 CR-V LX 4WD:

1st: nearly 100% highway, 29 MPG (!), speeds of 60-75 MPH.
2nd: nearly 100% city, 22.5 MPG
3rd: almost exactly 50/50 city/highway: 25.5 MPG

I was originally planning to get a Ford Escape Hybrid, but the dealers around here are all gouging and want $3000 over MSRP for it, making it ridiculously expensive. The CR-V has certainly been a great alternative. The performance and mileage of the 160 HP 4-cylinder and 5 speed automatic have been excellent. If it gets better as it breaks in, I'll be amazed. For reference, the EPA rating on the CR-V is 22 city/27 highway.

ateixeira

Took a road trip to Vally Forge, PA, and back to DC, and managed 28mpg. 2 adults in car plus luggage.

A/C was on the whole time, so not bad.

-juice

jayp1

I'm waiting to hear from gmtech ! Did I miss his post? I'm buying a 2001 Suburban 2500 4x4 with the 8.1L and I'll be looking to do a "Suburban Renewal" project to help on the performance and mileage. I'm thinking of easy to do things like K&N, lubes, chips, and maybe better pipes when its time to replace them, but I'd love to hear what gmtech or others have tried and recommend. I'll report my efforts here when I get started.

paisan

So far for the first 4k miles averaging 13.8mpg in city driving, not bad considering 305hp/385lbs torque on 87 octane. If I start running 91 octane hp goes to 315/395lbs torque.

I'll report back after I take a trip with it. And again after towing with it.

-mike

davola

I use Amsoil and C&K air filter and I get 26 mpg hwy and 24 mpg combined and 21 mpg city. I get about the same as my wives 2002 Forester.

ateixeira

Go diesels, that's amazing.

-juice

ferg1

Interstate gas mileage at 70 mph: 24 mpg
Around town: 19 mpg

My secret so far: keep my foot out of the throttle. This is the biggest, most powerful vehicle I have ever owned and I'm surprised at how effortless the engine is at moving a 2 1/2 ton beast around. I try to keep rpm's at 2500 or below. RPM at 70 on the interstate is about 2000; 55 mph about 1500. I am very happy with the milage I'm getting since I expected about 16 & 20. A great truck!http://a332.g.akamai.net/f/332/936/12h/www.edmunds.com/media/townhall/webxicons/emot- orcons/emo_smiley.gif
smile

dardson1

This thread seems like a perfect place to admit I record MPG on a spreadsheet and have done so for years. I've still got a paper MPG log on my bright orange 1972 Datsun 510 wagon. It averaged 20-21 in town, 25-28 on the road, and probably weighed in at 2400lb. It was a standard transmission 4cyl. with after-market air that over-heated if driven hard, and maybe 100 HP (can't remember). It, maybe, got to 60 in 14sec. I now drive an 04 Tahoe, with almost 3 times the HP, gets to 60 in 8+ seconds, has 4 times the room, 20 times the luxo-level, and the darned thing consistently gets 15 in town and near 20 HWY. It ain't 21/28. . . but, pound for pound my Tahoe is an econo-car by 1971 standards.

stever

Darn I'm jealous. I've been keeping logs since my '74 CJ-5 but I always left them in the car when I sold them. I'm sure they wound up in the trash instead of being cherished. I kept my '82 Tercel long enough to transfer those numbers into a spreadsheet.

Steve, Host

ateixeira

I have one for my Forester since 8/'98. In Excel. :-)

26.8mpg on this last tank.

-juice

chiefjs

I have a new CRV SE. My first two tankfuls with a combination of highway and city driving averaged out to about 24 MPG.

This last tank with most city drive was only 21.7 MPG. This is the first tank after I lowered the tire pressure from about 44 psi to 30 psi which is close to the recommended 29.

another_person

Is anybody out there using a product that actually increases the mpg on an SUV? If someone has something specific to a 2000 Toyota Land Cruiser, that would be great.

paisan

Just got back from roughly 2000 miles of driving...

Averaged 12-13 mpg on my trip. Which you might think is BAD, however...

I was towing a 6,000lb trailer and the truck was fully loaded with race gear. This was in the very very hot and humid weather we had in the East 2 weeks ago and towing with Full-blast AC and through the hills of WV, PA and NYS. So overall I can't complain at 12-13mpg for that trip. Oh yeah that was doing 75mph too.

-mike

ateixeira

That's near the EPA city without a trailer.

FWIW, my mileage while towing a 1500 lbs or so trailer went down about 31% compared to my average mileage. You give up a lot while towing.

-juice

paisan

Yup the 5-speed on the Armada is sweet. In the 2000 rpm range at 75mph

-mike

blueiedgod

Is anybody out there using a product that actually increases the mpg on an SUV? If someone has something specific to a 2000 Toyota Land Cruiser, that would be great.

I tried the controvercial "Acetone in gas" approach. It improved gas mileage on 2005 CR-V manual from 22 to 24 mpg city. Problem with Acetone, it only works with pure Gasoline. It lowers MPG when used with ethanol laced fuels (Gasohol), so you have to go to Exxon/Mobil, Shell, BP or Amoco for fills ups. Others may use up to 10% Ethanol. Is it worth it to fill up at $2.35 at Exxon and get 24 mpg, or fill up at BJ's at $2.25 and get 20 mpg?

Acetone has a sweet spot, that I have yet to find. People on the "acetone board" reported 30% improvments. So far I have been adding 3 oz of HPLC grade acetone to 15 gallon tank, which equates to 2 oz./10 gal. The sweet spot is somewhere between 1.5 oz/10 gal and 3 oz./10 gal.

Another positive effect of acetone is slightly increased torque and HP. I notice that when I run on acetone, the A/C lag is almost non-existent.

another_person

isn't acetone suppose to be bad for the engine seals?

blueiedgod

isn't acetone suppose to be bad for the engine seals?

3 oz per 10 gallons works out to be about 0.003%. If engine seals are vaulnerable to such small amounts of acetone, then it is a poorly designed engine. I can see how fuel delivery system seals may be at question, but "the other" site showed that seals soaked in pure acetone for 3 months were not affected.

The only things acetone is bad for is paint and oil producing countries. Acetone reduces surface tension of gasoline allowing it to atomize better in the combustion chamber, thus exposing every molecule of gasoline to air for complete combustion.

tidester

3 oz per 10 gallons...

Actually, that works out to about 0.2%

tidester, host

sonchar

Just got my new pathfinder at the end of May and have been averaging around 21 mpg combined...it is hard for me to estimate what city is because I live in rural AZ and there really is no city driving...I am using premium unleaded and the best I have gotten is 23.2 mpg....

here is a question, we just recently took the Pathfinder on a 3800 mile trip, all highway, from here to Minneapolis and back...the beginning of the trip I was doing around 22 mpg through some of the higher elevations of AZ and UT, dfferent speeds, from 55 mph up 80 mph...I was pleased...I was thinking when we got to some of the flatter states like Nebraska and Iowa the gas mileage would be better however in those lower, flatter states my gas mileage actually became worse...on our way back from Minneapolis we were driving through Kansas and I was barely getting 20 mpg...once we got in the the mountain states again the gas mileage went back up. Colorado NM and AZ we started getting mileage above 22 mpg...I cannot figure out why the mileage was so different...is there an additive in the midwest that is not in the west states or the other way around or is there a setting in the fuel systems were the SUV can be set for higher elevations driving?

stevedebi

The mid west uses galahol, you have to be careful when you fill up. However, it is usually the mid grade, not premium.

explorerx4

maybe all the tanks really had regular in them, or the meter was off.

paisan

The speeds would effect your MPG more than elevation. If you were going even 10mph slower on average in the mts than the plains that could explain it.

-mike

blueiedgod

The mid west uses galahol, you have to be careful when you fill up. However, it is usually the mid grade, not premium

Higher octane gas usually has more Ethanol as it is a cheap way to boost Octane ratings.

Does pathfinder require premium gas? I thought it had the detuned VQ35 from the Z350, which does not have the high compression in the Pathfinder version. Or so I thought.

paisan

In 05 the Pathy has the 4.0L and gets about 10hp higher than the frontier which runs on regular.

Similar to the Q56 gets 10hp and 5 torque more than the Armada from the same engine, the A runs on regular, the Q56 runs on premium.

-mike

ateixeira

Gotta agree with mike here, your speed affects mileage the most.

When we go on long road trips and take shifts driving, my wife always does 2-3mpg better than me on trips. She goes about 60-65, while I go 75 (usually in a 65 zone, so 10 over).

-juice

stevedebi

Not in Iowa, where I occaisionaly go for business. There, the mid grade is the one with the Ehanol. Premium does not carry the "high Ethanol" warnings on the pump.

stevedebi

"The speeds would effect your MPG more than elevation. If you were going even 10mph slower on average in the mts than the plains that could explain it."

In general I agree, but the best MPG I have achieved in my 2003 CR-V all occurred at high altitudes (above 5000 feet). Some of those tanks were at 75 MPH, and I went to 30 MPG. I sometimes think there is an error in the fuel mixture that Honda should look at - the car performs and gets better mileage at higher elevations.

My absolute best mileage of 31.2 MPG was at mixed highway speeds - 1/3 at 60 MPH, 2/3 at 80 MPH, all at high elevations in northern NM and Colorado.

sonchar

the speed was about the same, the trip was all interstates...and yes I was using premium...the 05 Pathfinder will run on regular but premium is recommended for optimum performance...

I called the dealer on this and the service department said that I am not the first to notice it and since the fule system is computer controlled the dealer said it is probably the additives...one of the local car service places is not so sure...he said the fuel mixture is controlled by the computer according to barometric pressure(?) and if enough people called Nissan they would make a change to the computer...

I'll call a different dealer to see if they give me the same reasoning and then I will try to contact Nissan...

arrie

Higher gas mileage at higher altitude...hmmmm...

Here is my crazy thinking about it.

It is most accurate that the speed has the greatest effect to gas mileage during highway driving. Wind resistance is almost the only friction to push the car through. Of course there are other factors, but these other factors pretty much remain the same during driving regardless of the speed so when going faster gas mileage goes down due to higher wind resistance.

Now, when driving at high altitude wind resistance is lower because air is less dense. (This is why airplanes fly so high. It just takes less fuel from them to make the distance they travel, and of course less time as they can go faster). This means that maintaining any highway speed at 5000 ft altitude takes less energy to do than at 100 ft altitude for example.

Now then some argue that lower air pressure at higher altitude reduces the amount of oxygen in the mixture and this would lead to loss of power and lower gas mileage. True, if you are driving with full throttle. In practice at normal elevations the engine throttle is only slightly open at constant highway speed. This means that only a small portion of the full capacity of air flow to engine is in use. When you go to higher altitudes the throttle must open more for the needed power requirement but as long as you do not need to drive with wide open throttle you are in controlled range. This means that when you are at high altitude your engine can give you the power it needs unless you are going up a really steep hill or towing heavy load. Steep hills and heavy towing can cause the engine to operate at full throttle and then the engine is at its limit and just can't give more power resulting in bad performance and low gas mileage.

Today's cars (at least some of them) have very sophisticated systems to measure amount of oxygen entering in the engine (MAP, MAF, intake temp. sensors) and then there are those O2 sensors to fine tune the system. This all can result in really good gas mileage especially while driving in high altitudes.

Food for thought...

--Arrie--

regganae

Using the mpg computer, I got 39hwy, and 18.9 city using regular unleaded. This was by cruising the highway at 68mph. I found the tips on conserving fuel economy in the manual to be rather helpful. I am concerned about how much I will be averaging in Germany on the autobahn, at around 95mph.

stevedebi

"Using the mpg computer, I got 39hwy"

Better check the computer, or did you mean 19 MPG highway? Otherwise, what the heck kind of engine do you have in that Pathfinder?

regganae

Exactly, I have no idea how to use that thing, but that is what it said. Actually, it said 18.9mpg (I think) and 39mph. I was hoping someone could explain this to me. I was thinking that 39mph was what I was getting on the highway, and 18.9 was what I was getting in the city???

arrie

My '04 Tahoe gives me:

24 - 26 MPG when I drive 45 MPH.

22-23 MPG with 50 MPH

19 - 21 MPG with 60 MPH

18 - 19 MPG with 70 MPH

17.5 - 18.3 MPG with 75 MPH

--Arrie--

tidester

I just wanted to see what that looks like as a graph and, since I did, here it is!

tidester, host

regganae

ok!! I think I get it now. I feel like a dummy! Thanks for the breakdown.

paisan

That is your average speed. On the pathfinders you get an average MPG and an average MPH So for your overall trip since resetting the computer you averaged 19mpg and 39mph.

-mike

blueiedgod

After the car has been properly broken in and oil changed to Mobil 1 0W-20, my 95% city driving fuel efficiency is 24 mpg (average of 3 tanks) using Mobil 87 gas (same station, same pump, the price has changed from $2.29 to $2.39 to $2.58 at last fill, ouch!!!).

I am running 3 oz of Acetone per 15 gal now to make another determination.

Previously, before car was broken in, before Mobil 1 oil change I was doing 22 without acetone and 24 with acetone. I expect 26 mpg average with 3 oz of acetone per 15 gal of fuel, 95% city driving.