DCT vs Manual MPG

[donovan]

Originally Posted by michaelw9

If you drive 10,000 miles a year, and average 16MPG, that's 625 gallons of gas. If you get 17 MPG with the DCT instead, that's 588 gallons of gas. So you would save 37 gallons in a year. So if gas is $3.15/gallon, you save $116.55 per year on gas. And that DCT is how much? $2900? Given gas prices staying the same, you would need to keep the car for almost 24 years to have it neutralize out. Get the tranmission you like to drive most.

A+

[mkoesel]

Originally Posted by z00m

I guess you can always safe fuel in neutral on manual - going downhill or so. Nobody does it,but if your computer shows "----" about miles left to drive with fuel - it's a real deal,isn't it?

You can put a DCT in neutral too. In fact, you can put any automatic transmission in neutral, probably even a CVT, so I don't really understand where you were going with this comment.

Anyways DCT should be a little bit more thursty then manual

Fixed.

And, no, not likely.

[Scoobe]

"... in a conventional manual transmission, there is not a continuous flow of power from the engine to the wheels. Instead, power delivery changes from on to off to on during gearshift, causing a phenomenon known as "shift shock" or "torque interrupt."

"...It (DCT) certainly offers smooth acceleration by eliminating the shift shock that accompanies gearshifts in manual transmissions and even some automatics."

"Perhaps the most compelling advantage of a DCT is improved fuel economy. Because power flow from the engine to the transmission is not interrupted, fuel efficiency increases dramatically. Some experts say that a six-speed DCT can deliver up to a 10 percent increase in relative fuel efficiency when compared to a conventional five-speed automatic."


I didn't buy my M3 with the DCT hoping for better fuel economy. Even though an improvement with DCT is likely, I doubt you'll notice or even care. If you do, you're probably shopping the wrong car.

[JCtx]

Difference is negligible. And remember DCT has, what, 10 settings? So mileage is going to be different on all 10 .
As far as top gear, I remember correctly 3K in 7th equates to 74 mph, vs 72 on the 6MT; hardly any difference.
And as somebody pointed out, even if there's a difference in fuel economy, you'd need to drive the car at least 14 years to break even with the extra $2,900, so just choose what you like the best .

Other subtle differences to consider are these: DCT shifts smoother and it's quicker than 6MT, if you care. The pleasure of driving a manual is much greater than those 2 advantages for those of us who enjoy the challenge and reward of having total mechanical control of your shifting. And the clutch pedal is so light (especially in newer models) that effort is not an issue even in heavy traffic. I'd definitely recommend you drive BOTH, then choose the one you like best. Good luck.

[Advskier]

I love the DCT transmission, and wouldn't buy an M3 any other way. But if you save around $3k going MT, and put 20K miles a year on the car, it will take a heck of a long time to make up the difference in cost, if there is a difference at all.

[Scoobe]

Originally Posted by Advskier

I love the DCT transmission, and wouldn't buy an M3 any other way. But if you save around $3k going MT, and put 20K miles a year on the car, it will take a heck of a long time to make up the difference in cost, if there is a difference at all.

Honestly though, people shell out big bucks for hybrid cars that they will never get the efficiency out of in dollars. Hasn't stopped them from buying. Hybrids have actually grown over the years even though they make no sense to the pocket book. Take the difference between a hybrid and an identical non-hybrid car, stick that cash on a gas credit card and you won't have to pay for a fill up for years, probably about the time you have to shell out big bucks to replace the batteries in the hybrid. Still, people buy them, makes them feel better seeing the mpg rating and filling up less often i guess.

[dimabimmer]

... if you are thinking MPG, M3 is not for you... M3 is the worst gas milage I've ever experienced, my first week was 13 MPG Highway, but it was so bad because the car was new, tires etc,. Now I get 18.5 MPG ... but I don't care... every gallon is an absolute thrill! Get the M3 and don't worry about MPG, you will be very happy.

[dimabimmer]

Originally Posted by elp_jc

Difference is negligible. And remember DCT has, what, 10 settings? So mileage is going to be different on all 10 .
As far as top gear, I remember correctly 3K in 7th equates to 74 mph, vs 72 on the 6MT; hardly any difference.
And as somebody pointed out, even if there's a difference in fuel economy, you'd need to drive the car at least 14 years to break even with the extra $2,900, so just choose what you like the best .

Other subtle differences to consider are these: DCT shifts smoother and it's quicker than 6MT, if you care. The pleasure of driving a manual is much greater than those 2 advantages for those of us who enjoy the challenge and reward of having total mechanical control of your shifting. And the clutch pedal is so light (especially in newer models) that effort is not an issue even in heavy traffic. I'd definitely recommend you drive BOTH, then choose the one you like best. Good luck.

+1000 Very well said sir

I love 6MT in '11 M3 is perfect, much better than in my previous 335i

[Advskier]

Everybody loves to trash talk the M3 milage. Try driving a Dodge 1500, or any number of large trucks or SUV's. It's a 414HP NA 4L V8 for petes sake.
Why would anyone even consider this car if that is even a slight concern???

[Scoobe]

Alright, going to throw a grenade out there, but some of the M3 MPG threads on this board show a wide disparity in MPG between the DCT and 6MT. Probably has more to do with 6MT drivers shift habits as a whole than anything else. Since I've owned my M3 DCT, I've never seen below a 18.0 average, while many 6MT guys are posting 13 and even 11 averages. Again, I'm not saying its the DCT, except for maybe it providing a more efficient "default" driving when not pushing the car, which might be more difficult to do in a 6MT rev match shifting. Easier to run the revs up a little bit higher than the DCT would before shifting.

Now I'm going to back away slowly and put on the flame suit.

[piloto]

Originally Posted by Scoobe

Now I'm going to back away slowly and put on the flame suit.

Dude, you're supposed to put the flame suit on before!

[prichards516]

i have 325 miles on the car (mostly city) and im averaging 13.4mpg