assyrianme

I just picked up a diesel and love it. I see that the transmission (I think a Aisin TR-82SD who make transmissions for Toyota) shifts so many times, even at low speed.

My theory is that Sport mode keeps the gear longer and shifts fewer times which should elongate the life of the transmission.

What do you think?

deilenberger

Whatever makes you happy.. I personally have never thought about this since the Aisin transmission is noted for longevity, even when not serviced. Taking your logic - would running in sport mode wear out the engine faster due to more revolutions per mile? If so - I'd rather have the transmission wear out - it's cheaper to replace.

assyrianme

That's a good point. Not sure if an engine's life is affected much at 2k or 2.5k revolutions. Higher is obvious and there is debate if lower, like the 1k range doesn't deliver enough oil pressure, hence you shouldn't idle to much, especially in the winter.

deilenberger

The oil pressure on a Cayenne is computer controlled (at least on the V8's).. but more RPM/mile = more engine wear/mile - no way around it.

hotrod2448

I think any time you go somewhere you should just drive home in reverse to take off the miles you put on going wherever you went. Your car will last forever that way.

If we are going to be serious... no. If you want to drive in sport because you like the way it drives great but, don't think you are extending the life of any component of your car by doing it. A lot of modern transmissions will up the hydraulic pressure in sport mode and shift harder so that's probably not going to be good for longevity. The input shaft of the transmission will be turning more RPM because the engine is turning more RPM because trans is in a lower gear which will generate heat and wear on both the trans and engine while also hurting fuel economy. Every accessory on the belt drive of engine will be wearing out faster because it is turning more RPM for a longer period of time. Because your engine is turning more RPM you are using more fuel, you are wearing out filters more often, your fuel pump is working harder, etc...

wkearney99

Porsche shifting takes some.... getting used to...

My gas GTS holds onto downshifts much more aggressively than the SUV it replaced. And this is just in normal mode.

In Sport mode it's much more aggressive. Like it's taunting me to go faster...

reach into those RPMs, downshift, hammer it, c'mon... don't wuss out!...
oh... fine... I'll upshift... slowly... one.. gear.. at... a... time... resigned to grocery-getter driving mode...

In short, you get used to it. Leave it in normal mode.

wkearney99

Ok ...

BenCD

As I have heard that the 8-speed transmission was/is rated for some 600 or 800 -HP, it is overbuilt and for all the years that it has been in the Touareg, I have not read of any issues with transmissions in the diesels.

TXCOMT

Man, that is so true...my wife won't even drive her '14 S in Sport and it's her DD! I, however, plan to do exactly that tomorrow while she's hosting some party at our place. Our little girl is gonna get an eye-opening run in that thing, I promise you!

TXCOMT

assyrianme

Very interesting. I was thinking the engaging and disengaging of the clutches so many times would wear out sooner. Also, my thought was that lower rpms at higher gears causes more stress on the vehicle. Maybe I was thinking manual transmission.

Funny, my Japanese Isuzu VehiCross has a German transmission. Now my German Cayenne D has a Japanese transmission.

TXCOMT

VehiCross! Haven't thought about (or even seen) those in years...wow!

TXCOMT

importtuner

From what I've been told, its usually heat that kills transmissions. Most modern day autos have at least 7 gears. Some have 10-speeds. The Aisin units are very stout and common across many brands.

Elberoth

Our Aisin transmission is rated at 850Nm of torque. The diesel only produces 550Nm or so. It will outlast the car.