Is there a difference in the MPG from auto to manual in the xb2s? Edmunds.com says no. What do you guys think?

 

If not, I wonder why it wouldn't be better off, especially being 5-speed.

I have an auto, and average 29.XX something over my last 13 fillups or so. I do pretty well but drive quite a bit of freeway too. But I do wonder why the manual/auto get the exact same (reported).

 

manual transmission cars can easily get more mpg than an automatic because 1. they get more power to the wheels, 2. the driver has more control over the engine speed and therefore fuel consumption, and 3. automatic transmissions can only respond, they can't anticipate manuevers that the driver can.

anyway, edmunds can only publish EPA fuel estimates and maybe their own personal findings. the epa estimates leave many factors out of the equation for factoring fuel consumption. so your mileage will vary.

 

This is what Consumer Guide got..

 

gee they must have led foots


i know in the tC the manual gets worse mileage on paper then the auto ( doesnt really if you drive right) but thats due to the aggressive gearing. im would imagine that the aggressive gearing wouldn't have followed threw to the xb though

 

I have an auto with 17" wheels and I average 23.9 around town.

 

That seems kinda low to me.

 

Most of this is NOT true.

The auto and manual are about the same in fuel consumption.

This sounds like the dudes that were convinced they can stop better in a car without the ABS vs a car with ABS.

 

Who are you talking to?

 

You. 23.9 seems kinda low to me.

 

Really? I am very happy with it. I only work 1.5 miles from my house and very rarely drive over 40 mph. What do you get around town?

 

the engine consumes the same amount of fuel, the the manual will pwn the auto because it has more gears, which means more ratios for keeping rpms high or low, and loses less power on the way to the engine, so there fore it can accelerate faster using less power (fuel) than an auto. also, when you engine brake, you are using no fuel. and i think ABS is one of the best inventions since sliced bread.

 

You forgot one thing.

The computer is far better and knowing when to shift than any of us.

 

Well if that's the case then it's not bad I suppose. I don't have an xB yet. I'm waiting on my WRX to sell. Hopefully this guy thats really interested will buy it.

 

the computer can perform way more calculations and so on than any human can, this is true, but the human has one major advantage over the computer, it can see, you can look down the road and anticipate necessary gear changes that the computer and automatic transmission can't. the auto can only react to what the driver is trying to tell it through the gas and brake pedal, and what the engine speed and load on the car is etc. it can't preemtively shift for you like you can with a manual.

 

Consumer Guide not to be confused with consumer reports. I purchased that mag and their specs and reviews are total **** for all the cars. They dont test the cars in a standard way. They said the civic SI had a 1.8 liter natural gas engine and go the best mpg of all the non hybrid civics. they are idiots

 

the computer cannot shift better than anyone. That is the primary problem with the automatic, they waste energy. They typically rely on a torque converter the mechanically shifts the gears. Think of it as a rubberband that when stretched enough will finally respond and shift gears. More modern autos do involve computers but that doesnt help matters.

One thing an auto cant do that a manual can is coast. If i coast in an auto the RPMs of the motor are typically 1-1.5k If i am in a manual and i shift to neutral the engine drops to idle at 0.5-0.75k. Thus using less gas.

The only auto trans out there that can get power to the wheels as efficiently as a manual (ie not using the torque converter) and do so smoothly is the DSG (the audi and VW trans). It is brilliant in design but i still think a human driver could best its mpgs.

go to fueleconomy.gov and check out the mpgs users are reporting. Notice how the manuals almost always are above teh EPA ratings. Not so much with teh autos.

 

Ok, in our Sienna, which isnt geared toward performance in any way at all, when you're coasting, it feels like it shifts into the highest gear it is "allowed" (by your gear selection). Now this is annoying when you want to accelerate again, but is an example of how the autos may be getting close/same MPGs. Also, sometimes in a manual you might get lazy, and delay the upshift. The higher RPMs result is increased fuel consumption, where in a auto, the computer is always waiting to upshift at the earliest feasible moment. (Overridden of course by how far you have the pedal down).

 

yeah we have a sienna too and if you coast it stays at a highish rpm. If you instead shift to neutral you will see the thing drop to 750 rpm. This is that coasting difference i was talking about that is an advantage for a good manual driver. Sure a bad manual driver might shift at the wrong place but if you know how to drive i really think the manual owner will top the auto unless there is a large gearing difference between teh two. Problem with autos - you pointed out there - is that they dont know when you want to downshift or not. Often you want to accelerate mildly but the car decided to down shift right as you are dont accelerating at which point it upshifts again.

But basically go light on the gas with an auto and drive like a normal person in a manual and you prob see similar mpg. But learn your car, and pay attention, and you can do better with a manual.

 

Actually, while coasting, the car (in theory) shouldn't consume any more gas then at idle, otherwise instead of engine braking, it would be trying to go forward. The difference comes in how much speed you pick up while coasting.