Hi Guys,
A friend of mine has a 2009 Porsche Cayenne S. Recently, she drove up a hilly road to a red light. Rather than step on the brake, she continued to lightly engage the accelerator which caused the automatic transmission to provide enough torque to keep the car at rest, more or less. I think that it is better to step on the brake until the light is green as this constant revving of the engine would damage the transmission not to mention wasting fuel.
Thanks for your advice!
You Didn’t Mention The Safety Aspect. Should The Porsche Ever Be Rear-Ended At That Intersection, It Would More Easily Be Launched Into Traffic. Considering Everything, Why Do It ?
CSA
It most certainly wastes fuel and may not be the safest way to hold the hill but he probably is doing little harm to the transmission itself. The torque converter is just stirring oil and the resulting heat is taken care of by the oil cooler. Nothing is physically slipping like a clutch on a manual transmission.
Doing this with a manual transmission will have you replacing the clutch often.
CSA is right, this is a very unsafe practice.
B.L.E. is also right that the torques converter is just churning tranny fluid, th eheat generated being dissipated by the tranny’s cooling system…but I see no purpose in generating the extra heat needlessly.
As you said, it’s better to use the brake. But your friend hasn’t asked, so my recommendation is to ignore it and not try to change her driving habits. If you do she may end up being an ex-friend. Unsolicited driving advice is rarely well received.
Make sure you don’t consider buying the car from your friend or let her drive yours.
It isn’t recommended. It is specifically not recommended in some owner’s manuals.
Thanks all for your excellent advice. The Cayenne seems to be a well built car but no car needs excessive wear and tear! I will keep my mouth shut regarding giving her free advice… unless I see smoke coming out from the tranny… or we are hit from behind. I pity the car that hits this monster, though…
Happy Holidays!
Right away i think of the old brake stand days. Those transmissions always held up and i doubt her using the tranny as a brake at a light on a hill is going to get anybody killed. An airplane could crash at the stop light n kill somebody. Some of you guys get a little extreme with your picking things apart
“I pity the car that hits this monster, though…”
You should also pity the woman who owns that monster.
Cars that are expensive to buy are even more expensive to repair, and they frequently tend to be more difficult to repair properly.
By the way…can you explain the concept of this high-performance SUV to me?
This vehicle seems like the unification of two totally disparate concepts.
By putting “brake” and “light” so close together in a sentence, Peacefrog inadvertant brought up another good reason not to get in this habit: your friend’s brake lights won’t be on. Hopefully, there won’t be a situation where at dusk some day someone driving home half asleep doesn’t miss the fact that she’s stopped and plow into the rear of her car. It HAS happened.
Sounds hazardous but there is a street light lite up red and a car stopped. Inattentive drive hazard i suppose