Highway driving with minimal city, according to the navigation calculator, I get 23 in Auto vs 21.6 in MM. Amoco 93, no performance mods, an Infiniti black leather bra, no rear spoiler, G35X. It seems that when you take your foot off the gas in Auto, the engine revs drop down at lower speeds, which allows the car to coast thereby getting more MPG, whereas in MM the revs seem directly linked to the speed maintained. Anyone care to expand on the transmission differences between the two modes of operation.

 

No offence mate, but you have way too much time on your hands. If you can afford a 35k car then the cost of petrol should not be an issue.
As regards your technical data, WHOA!!!!!!! Maybe I should read more.
I apologise in advance, I'm being very rude and don't mean too be....

 

When I drive in MM mode, it seems the torque converter locks later than auto mode thus the rpms are higher in mm mode.

04 Coupe Auto/DG/Prem/Nav/Perf

 

britishbloke,

$35,000 is not that much for a car now a days. A well equipped minivan can run north of $30,000. Besides, what's wrong with being frugal, thrifty, or cheap when it comes to things like gas...

g4ian



369192-G35 MINI.jpg

 

<blockquote><font class="small">In reply to:</font><hr>

...but you have way too much time on your hands

<hr></blockquote>

C'mon bloke, a comment like this from you of all people? Talk about the pot calling the kettle black! [img]/w3timages/icons/laugh.gif[/img]

But to the issue at hand, maybe it's possible that you drive more aggressively in MM than in AT? I know I do.


<font color=red>chinee</font color=red>
03.5 G35s

 

Chinee, I definately drive more agressively in MM. Perhaps my title for the post was misleading. My real question here is, what's going on in the tranny that causes the rpms to drop down at lower speeds (in Auto) compared to driving in MM where it does not seem to drop off. The result of course is more MPG driving in Auto.

Bloke, I wish I had more time on my hands. Na, the money is not the problem. No offence taken mate. I've read enough of your posts to get a feel for your comments. I'd like to hear what Q45TECH has to say about the tranny modes, or from anyone else with knowledge of these technical issues.

There are times when one must use MM to downshift and pass with authority. The car demands it, regardless of the price of gas!!

 

04_G35XPN wrote -

"There are times when one must use MM to downshift and pass with authority. The car demands it, regardless of the price of gas!!"

I think you just answered your own guest ion. MM mode is more performance oriented, while auto mode is more economical. I think!!

03.5 G35S 5AT - Desert Platinum/Graphite/Clear corners/HG kit/20% Tint

 

Allright, allright...I already aplogised. I was simply being absurd.

 

I drive a 6MT, so I'm kind of theorizing here what is happening for you guys. In regular Auto mode, when you let go of the gas, the car is most likely just upshifting into a higher gear, hence the drop in RPM's. It's probably programmed to do that to help with gas mileage.

In MM mode, program changes and the upshift is probably being "locked out". For example if you are in 4th gear and you let go of the gas, it stays in 4th and does NOT upshift to 5th.

 

The auto will shift most effeciently and properly in the Auto mode. This is the computer controlled method and probably can't be improved on (for efficiency and economy!).

Manual mode is so much more fun, and will be much more uselful in more spirited driving, tho not as fuel efficient. You'd expect that.
I can't see it being more than 2-3 mpg's different tho.

<font color=red>GSM</font color=red>
<font color=red>GSM</font color=red>
<font color=black>Silverstone Coupe</font color=black>

 

A side note, if I may...

I find that my G35x AT is at 3000 (I think) at 80 in 5th gear and it seems to be at pretty high revs, albeit with 5 gears...

Shouldn't it be at 2500 at 80? If someone can enlighten me it'd be appreciated...

 

Nope. Its right around 3k. The VQ has always been aggressively geared at freeway speeds (3k at 80mph). My Maxima was the same and so were other iterations of the VQ. My coupe is 3k at 80mph.

04 Coupe Auto/DG/Prem/Nav/Perf

 

I think your right because when I drive m.m. i really felly the engine rev. up