Never owned one myself, but was wondering - for no specific reason - that if you sat in traffic for a long time with it in DRIVE, but with your foot on the brake, would it have the same effect as an manual and holding it on the bite point of the clutch for a long time - ie, eventually burn out the clutch?

 

Having an auto X5 i wonder this myself. I usually slip it to park if on a hill or neutral on a flat surface if i'm sitting waiting.

Also, sitting on a hill in drive you can come off the brake and the car just holds there. Now if you were slipping the clutch that'd be bad but i dont know if this is in auto and whether some clever system balances car on a brake...

 

im sure i remember reading some were leaving an auto in drive for too long can damage them eventually. but i think it takes quite a while before you would do any noticable damage

 

it can't burn out the clutch - it doesn't have one

the fluid in the torque converter can overheat though. if you wonder about something, google can be used to answer many questions

 

I love Google, and use it for nearly everything - but it's so rare for me to put a car-related post, I thought I would

 

as nick said, there is no clutch, just fluid in the torque converter

http://en.wikipedia.org/wiki/Automatic_transmission

have read and learn something new

 

The torque converter will over heat, but that will take some time

 

Saw a debate about this a month or two ago on a Jaguar forum, in among the tweed jacket buying guides and pipe tobacco reviews. The basic consensus was that yes, leaving the car in drive for ages and ages and ages and ages would ruin your torque convertor, but that most auto boxes are designed to be left in drive at the lights, and to move them out of drive into neutral every time you got to the lights would add as much wear and tear as not doing so. So it's six of one, half a dozen of the other really!

 

if you are sitting in traffic for long periods of time or stationary for more than a few minutes, it's always advisable to stick it into neutral

a bit of interesting news for you though that is along the same lines:

the old routemaster buses were notorious for blowing up torque converters, something in their design meant that when they got hot, they exploded, so the mechanics drilled holes into the torque converters, plugged them with lead and left them at it

this way the lead melts as the oil gets hotter and blows a hole in it, simple to replace the lead plug rather than the whole torque converter

centrecom also made sure that drivers were reminded to put the buses into neutral when stuck in traffic

 

They DO HAVE CLUTCHES, to operate brake bands, they have one called a sprag clutch also that operates as a roller clutch for routine up downshifts.
Mondeo's for example are famous for breaking the fingers on the CLUTCH basket, a extremely similar set up to a wet clutch on a m/bike.
They don't have a clutch that operates in the normal way as on a manual box.
Automatic boxes such as on Ferraris(paddle shift) have more clutches as they can preselect as well.
tabetha

 

When stationary, I'd say it would literally take forever to overheat the fluid. Unless you were in a heatwave situation, stuck in traffic, messing with your foot on the brake, and accelerator at same time whilst in gear.

If there was a real concern... manufacturers would probably reccomend more regular ATF fluid changes as a minimum. Which most dont.

 

A well specced auto box will never burn out just sat on the spot, they are capable of losing the heat from the fluid quicker than they gain it, unless you are sat on the brake and accelerator at the same time.

 

And Ive tried that even on my crappy old Volvo.....it isnt easy to sit for long with foot on the brake and accelerator.
Its auto is near 240k now with zero problems