99stang

Hello,
I've been reading through the different threads about MPG and RPM's on these cars.

My main question is this:
Assuming the same driver, driving style, road conditions, weather, etc..., Which version of the TL gets the best gas mileage in the city/suburban environment? on the highway?

My gut feel was the 6MT with the J32 would be the best overall since one would think 6 gears would be more efficient than 5 and the J32 engine would burn less fuel than the J35 given the same acceleration and speed levels.

After researching though, I'm not so sure.
Below is my guess of the most efficient (assuming the 5AT is not being manually shifted):
A > B, where A gets better mileage than B.

City/suburban driving (mix of lights, stop signs and 45mph stretches):
3.2 6MT > 3.5 6MT > 3.2 5AT > 3.5 5AT

My thinking here:
Manuals should trump auto's in city driving since there's no torque converter to deal with and the driver has better control of skipping up to the top gear, starting in 2nd, etc...
Due to the lower 1st gear of the 6MT, the added power of the J35 (and weight of the type s) would burn more gas for the same effort of driving. I may be wrong here - perhaps both 6MT's would equal out in MPG.

I'm not sure which of the two 5AT cars would do better in city driving. The 3.5 has more power so it shouldn't need to be pushed as hard, but I believe I read the shift logic is more aggressive in the type s 5AT, so that may end up chewing up more fuel if the gears are held longer allowing the engine to rev more.


Highway driving (constant 70mph in top gear on a flat road):
3.2 5AT > 3.5 5AT > 3.2 6MT > 3.5 6MT

My thinking here:
I haven't found numbers for 70mph, but one thread mentions the 5AT runs at 2200RPM @ 80MPH, while the 6MT runs at 2750RPM.
Over a long trip on flat roads, the 5AT should burn less fuel. The J32 5AT should burn less than the J35.

Highway driving with hills (70mph)
3.2 6MT > 3.5 6mt > 3.5 5AT > 3.2 5AT

My thinking here:
As soon as hills are added to the equation - or even speed-up/slow-down road conditions on a flat road, the 6MT should come out on top again since the driver can leave it in 6th or maybe drop down to 5th where the auto will drop out of 5th gear/lock-up and the rpm's will go up.
How is the tl vs type s 5AT shift logic in hill/passing situations? Is the type s programmed to hold the top gear longer since it's got more power?

I look forward to hearing your responses.
For the sake of simplicity, I'd like to see the same A > B structure I have above in your responses.
Thanks!

99stang

I thought I'd get at least a few replies on this

justnspace

iTrader: (1)

interesting post. Very good read.
I dont drive mine consistently to get a good reading on my 6MT 3.2.

I know James with a 3.5 6MT reports *Ibelieve* 24mpg in stop and go. butt, I could be wrong.

Shoot2Thrill

Could you put a spread sheet up on google so we can add to every day with our data recordings. Maybe we can plot price we paid, octane, our weight, passengers and their weight, luggage and ambient temperature and other useless trivia. Awesome post amazing you don't own a TL

99stang

Thanks - I'll look into that - haven't done a Google spreadsheet before.
Something new to learn...

The site http://www.fueleconomy.gov/ has info on each make/model/year and consumer feedback on real world fuel economy.
If you have some good stats, I suggest that site so it will be available to a wider group of folks.

Another site with good info I've found is
http://www.truedelta.com/fuel_economy.php

I'm now wondering how much does # of passengers, luggage, etc... affect the mileage? My guess is not as much as one would think.
I think keeping the car well serviced (proper tire pressure, oil changes, etc...) and avoiding aggressive driving styles will make the most impact.

Does anyone keep track of their mileage from tank to tank?
I keep a small book in each car to record the gallons filled, cost, mileage since the last fill and the computer generated mpg - and reset the trip computer at each tank full.
The 06 Sienna has averaged 19.6mpg over 59000 miles (14-15 city to 26+hwy) (50/50 urban/highway).
The mustang has averaged 18.6mpg over the 10k miles I've driven it (75% suburban driving). That's with a heavy foot too.

imj0257

iTrader: (1)

...

3.2 5AT, One tank, 90% highway driving 70-85mph:

Best I've gotten.

99stang

Thanks!
As they say - a picture is worth a thousand words.
Do you think the trip computer is fairly accurate? The one on our Sienna seems to be a bit optimistic - reading 1-2mpg better than the hand calculations most of the time.

blkmz3

i get 32mpg consistenly doing highway. 04 TL 6spd. Mixed driving I get around 26-27.

imj0257

iTrader: (1)

LaCostaRacer

Unfortunately the MPG threads get a little boring since there are so many threads like this. I suggest going here and you'll get a lot more data on this stuff: www.fueleconomy.gov. You can do a side-by-side comparison and see that your findings are close.

The findings show the following:

2006 Auto & Manual are about the same: 21 MPG estimated and 25.7 actual

2007 Auto Type-S: 20 MPG estimated and 23.2 actual.

2007 6spd Type-S 21 MPG estimated with NO REAL WORLD data

My guess is if you wait for people to chime in, you will see values similar to what this web site provides. The web site is better because you get local and city/highway breakdown is a much more convenient form that reading a bunch of postings.

Jackass

Also remember that tires play a huge role in your overall MPG. On my 3.2 MT with the OE tires, I was 27 city and 31 highway. Once I put on Pilot Sports, I was 24 city and 27 highway.

FYI, my "city" driving is still averaging 35mph for the most part. It is my daily commute in rush hour traffic (25-40mph on highway) along with the 2-4 miles of stop lights to/from the highway.

SurfingScotty

<-- 6SMT 3.5 (Type-S) a couple full throttle 0-60 starts per tank, mostly city driving. Average 24-26 MPG per tank. I use my clutch a lot and take advantage of hills. I don't drive like a grandma but not overly conservative either.