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Weird Way to Control Descent

I did some Google searching this morning to see if I could find any information on this topic…there is nothing. Which probably indicates how crazy this topic really is.

So I was talking with someone yesterday—that someone shall remain nameless—who lives at the top of a steep hill and drives a 2009 Mazda3 with a 5-speed manual transmission. I believe the car is red. On snowy days, this person tells me that she will place the transmission into reverse gear (REVERSE!) and coast down the hill with the clutch pedal depressed and her foot on the brake, occasionally releasing the clutch just enough to engage the reverse gear, in order to control her momentum going down this hill. (Obviously, she can never fully engage the clutch.) She claims this to be an effective way of maintaining control of the car while she is descending this slippery hill to which my response is simply: BUT THAT IS NUTSO! I told her that if it were me, I’d have the car in first gear, the clutch fully engaged (not depressed), and pumping the brake during the extent of my descent. Who’s right?

And more importantly, WHY is that person (i.e. me) right?

Her way is crazy, of course. I assume there’s extreme clutch wear here. I can’t think of any reason why someone would think this is better.

As for your way, first gear may not be the best idea. You don’t want enough engine braking to cause the wheels to break traction and slide. Your engine doesn’t have ABS; your regular brakes do. You want a gear that keeps the speed down without causing any sliding. Then you want to use the regular brakes without pumping them.

Man, what people will do…
Her way is nuts of course. I’ll bet her clutch assembly life (including her realease bearing) is extremely minimal. Having the engine turning the gears one way while the car’s weight is trying to turn them in the opposite direction, and taking up the difference by slipping the clutch, is about the worst use of a clutch I can possibly imagine.

Well the engine is an OHC design (maybe DOHC but that is not important) which means it has a long timing belt or chain that has a tensioner. I don’t know why, but you are not supposed to let those engines turn backwards and that risk exists should her foot slip off the clutch for some reason.

Along time ago before ABS and TC I was going down a snow and sleet covered steep driveway in an automatic, rear wheel drive vehicle. While going down the hill the hole vehicle just started sliding down brakes on all wheels locked up, quick thinking I put the transmission in reverse and gave it gas, rear wheel spinning backward got the vehicle stopped before the bottom of the hill. After a change of underwear all was good. I definitely say don’t try it I got lucky.

She is nuts. You got that part right.

Definitely a good way to burn up a clutch at minimum, Would the same effect be achieved by judicious use of the parking brake? I can see little difference cognitively in outcome for driving control, and of course a way major advantage for the car longevity.

lion9car said it righ. And the brakes would work better than the clutch.

Not sure about the parking brake idea. Could cause the back wheels to lock up and spin the car around.

It’s drivers like this that made abs mandatory. Leave it to them to find a way of not using it
Just a suggestion…DONOT ride with this person in the winter. Tell her to Use the abs braking system. She obviously has no engineering background and can’t read. Maybe she will respond to the spoken word.

I wish they still took live calls! This would be a great call for the Car Talk guys to riff on.

I know! I miss Click & Clack. I explained to her that the whole reverse-gear thing is not a good idea when driving down a steep incline (or for any other situation in which you the car is moving forward), but I still think 1st gear is better to be in when driving down a steep incline than 2nd gear because the engine compression is higher in 1st and should do a better job keeping the car from gaining too much momentum. Do people agree with this?

She sounds like the original owner of my Matrix, who overheated the clutch enough in 8k miles to cause it to fail later at 32k miles.

""but I still think 1st gear is better to be in when driving down a steep incline than 2nd gear because the engine compression is higher in 1st and should do a better job keeping the car from gaining too much momentum. Do people agree with this? " "ancatdubh2 !st gear would be fine on dry pavement, but on slick roads, it MIGHT be better to use a higher gear. !st gear could cause the wheels to slide. However, the OP didn’t mention slick roads. Her way of doing it is rediculous.

First gear obviously offers more braking performance. But, EllyEllis is absolutely right. Some times you don’t want “more” braking performance especially braking performance that can’t be modulated to avoid loss of control…like on ice and snow. The only place on your car you can find assistance in maintaining steerage while braking on ice and snow, is with the abs system. If all you want to do is stop as fast as possible, find a parked car or tree to turn into. But, if you want the maximum benefits in braking, use abs !