What SHOULD get better MPG - Automatics or Manuals

ruknight4ever · #1 (**permalink**) 10-15-2008, 04:11 PM

Hello Everyone.. I have read the numerous posts regarding MPG for auto vs. manual transmission Fits. I'd like to know whether I will receive better MPG if I have a manual or auto Fit.

Some of my confusion when reading all of the other posts is that I don't really get a sense of how hard or easy people are driving their cars when they post their mileage. Are people running full throttle from a stop, are people hypermiling, etc?

If I am driving to maximize MPGs, will I get better MPG with the manual or automatic? I know the window sticker shows the same MPG for both the manual and automatic but I don't consider the EPA sticker to be 'real world". I am assuming I will get 10%-ish better mileage with the manual (assuming I drive both the auto and the manually conservatively) but wanted to know everyone's thoughts.

pb and h · #2 (**permalink**) 10-15-2008, 06:05 PM

Driving habits will dictate your mpg. One must develop new driving habits to achieve great mpg in an auto or a manual. For the FIT the manual will get better mpg.

What are your driving techniques and can you improve them is the real question.

ruknight4ever · #3 (**permalink**) 10-15-2008, 06:26 PM

I think you answered my question. Pound for pound, if someone has good driving habits (e.g. no full throttle starts, upshirting early, coasting, using the "driving without brakes" technique), I wanted to know whether mechanically the manual is better suited / designed to get more MPGs than the auto.

AnlDyxp_GD3 · #4 (**permalink**) 10-15-2008, 07:33 PM

I have a manual and i'm getting no more than 30mpg right now. Ive been trying to get atleast 35mpg but i always shift at 3k. I think shifting at 2k is too slow. I also get neverous when i see people passing me, I feel like i'm slowing down traffic for some reason so i always end up shifting at higher rpms. For some reason I also feel the need to drive fast when im leading on a green light at the intersection. My Fit only has 19K on it. Will my gas mileage improve as i put more miles on the car?

JDMxGE8 · #5 (**permalink**) 10-15-2008, 07:34 PM

MT usually gets better MPG than AT.

pcs0snq · #6 (**permalink**) 10-15-2008, 09:33 PM

It depends on how you rank FE.
If you want the best and plan to drive like you want the best, MT hands down. Just driving normal the MT is on Avg 5mpg better than AT.

All the cars in the 60mpg+ club are MT's

ruknight4ever · #7 (**permalink**) 10-15-2008, 10:29 PM

Paul.. thanks so much for your post. The statistic that "all cars in the 60 mpg+ club are MT's" is very telling. Can you point me to where I can research where people are getting that type of mileage? I had a Prius and sold it for a 2009 Fit. I only sold the Prius because it was in an awful accident (someone rear-ended me and pushed me into the car in front of me) and a dealer paid me for it what I paid for it 2 years ago (after the car was fixed, of course). So, fuel economy is very important to me.

Fitftw · #8 (**permalink**) 10-15-2008, 10:50 PM

MT usually gets the better gas mileage but it all comes down to how you drive and how much hypermiling you want to do.

cojaro · #9 (**permalink**) 10-15-2008, 11:10 PM

MT should get better MPG as less energy is lost between the engine and wheel/road than in an AT. However, a large factor is how the transmission is geared. The Fit's AT is geared differently than the MT. From what I've read, I'd expect the AT to get better highway mileage, the MT getting better city mileage. I've gotten no less than 30mpg in my MT and my last tank was 35.5, with no more than 10% highway.

kylerwho · #10 (**permalink**) 10-15-2008, 11:14 PM

quite a bit of drive is lost through the at transmission. mt are always getting better mpg as stated before unless your trying to race everyone who stages up next to you at all the lights. civil drivers are getting mid 30's to lower 40's in the mt consistently. my worst mpg was 22 but i was trying for bad mileage. my best is 46.

pcs0snq · #11 (**permalink**) 10-15-2008, 11:44 PM

Quote:

Originally Posted by ruknight4ever

Paul.. thanks so much for your post. The statistic that "all cars in the 60 mpg+ club are MT's" is very telling. Can you point me to where I can research where people are getting that type of mileage?

Two post in this Eco are all the time. Budgetfit Kyle and PB &H Shawn

Also in the cleanMPG form Honda area has another now and than. Go look at all the GAS cars in the Cleanmpg DB that burn gas. You will see lots of good Fits in action.

On this site there was a poll for AT and one for MT's that show lost of info. That's the source of my swag at 5mpg.

good luck

Fit4Pits · #12 (**permalink**) 10-17-2008, 05:42 PM

Quote:

Originally Posted by cojaro

However, a large factor is how the transmission is geared. The Fit's AT is geared differently than the MT. From what I've read, I'd expect the AT to get better highway mileage, the MT getting better city mileage.

If you do a lot of highway driving, as I do, you really have to slow it down to get great mileage. I drive 60 on the highway in my MT. That's right around 3000rpms. My aunt has an AT and at 65mph she's around 2600rpms.
Makes me qq, but I get almost 10mpg better than her and her lead foot.

On a side note, have any of you AT owners noticed that your Fit has to really rev to get up hills? My aunt's constantly downshifts on the uphills and revs to 4-5k rpm.

AnlDyxp_GD3 · #13 (**permalink**) 10-17-2008, 06:10 PM

Quote:

Originally Posted by Fit4Pits

If you do a lot of highway driving, as I do, you really have to slow it down to get great mileage. I drive 60 on the highway in my MT. That's right around 3000rpms. My aunt has an AT and at 65mph she's around 2600rpms.
Makes me qq, but I get almost 10mpg better than her and her lead foot.

On a side note, have any of you AT owners noticed that your Fit has to really rev to get up hills? My aunt's constantly downshifts on the uphills and revs to 4-5k rpm.

I have a MT fit and i noticed the high reving as well. I've had my fit for about 3 months now. And the first time i took it on the freeway it was at 3K going about 60-65mph so i thought it was kinda weird compared to my previous nissan xterra. doesnt it burn more gas that way? So would you get better mileage driving highway?

MINI-Fit · #14 (**permalink**) 10-20-2008, 12:22 AM

Quote:

Originally Posted by ruknight4ever

I think you answered my question. Pound for pound, if someone has good driving habits (e.g. no full throttle starts, upshirting early, coasting, using the "driving without brakes" technique), I wanted to know whether mechanically the manual is better suited / designed to get more MPGs than the auto.

If you took almost identical Fits and drove them on any roads and you used the very best technique for helping mpg you would find-

MT beats AT easily.

Basic expectations-

MT gets over 30 mpg (40 would be easy with light traffic).
AT gets under 30 mpg (more like 25 even when trying really hard)

But my dealership gets 1 MT for every 9 ATs.

solbrothers · #15 (**permalink**) 10-20-2008, 12:48 AM

Quote:

Originally Posted by cojaro

MT should get better MPG as less energy is lost between the engine and wheel/road than in an AT. However, a large factor is how the transmission is geared. The Fit's AT is geared differently than the MT. From what I've read, I'd expect the AT to get better highway mileage, the MT getting better city mileage. I've gotten no less than 30mpg in my MT and my last tank was 35.5, with no more than 10% highway.

although the gearing is different, and it'd seem like the AT would get better highway fuel economy, based on the gearing, the MT STILL gets better fuel economy city or highway. you must use more throttle to push the AT on the freeway, thus worse fuel economy

JCLW · #16 (**permalink**) 10-24-2008, 04:00 PM

My thoughts and observations:

I drive a '07 auto.

I have installed a "VTEC light" that tells me when the ECM has switched from the single intake valve profile to the dual intake valve profile.

I consider myself an average driver - 50% of the time I'm conscientiously trying to save fuel, and the other 50% of the time I'm late for work. I probably average 80% city stop-and-go, and 20% highway.

I probably only go WOT (Wide Open Throttle) a couple of times per year.

The 5AT in the fit is fairly sophisticated - it allows torque converter lockup in every gear, and also has grade descent logic (downshifts and locks the torque converter to allow engine braking if the ECM senses that the brakes are being applied and yet the vehicle speed is not changing).

As others have mentioned the 5AT is geared for lower rpm at highway speeds. This results in more downshifting when driving in hilly terrain You can drive faster and get the engine up in a torquier part of the powerband to eliminate some downshifting (but that doesn't really help fuel economy).

My best fuel economy / speed compromise on the highway seems to be just below the speed at which VTEC changes to the two intake valve profile (which on my car works out to ~110km/h or ~68mph).

My lifetime fuel economy average (after 2yrs / 35k kms) is 32 MPG (7.3 l/100km).

My average highway fuel economy (from my last three road trips) is 34.5 MPG (6.8 l/100kms).

I would think that the reduced friction and piston acceleration forces when using the 5AT on a relatively flat highway would offset the greater transmission inefficiencies. But maybe not if you're on a hilly road and always downshifting.

Quote:

Originally Posted by Fit4Pits

On a side note, have any of you AT owners noticed that your Fit has to really rev to get up hills? My aunt's constantly downshifts on the uphills and revs to 4-5k rpm.

Usually only to the 3.5-4k range. But I guess it would depend on speed and hill steepness.