Gear down?

[2o6]

I was on a test drive in a Kia Rio the other day, (5MT) and the salesman encouraged me to change down and let the car engine brake down the hill. I thought that was odd, because the hill isn't super long, or super steep. Usually, I kick it in neutral and control with the brake, it gives me more coasting MPH, and IIRC doesn't the motor use less fuel because the motor is near idle?


What do you typically do when going downhill? Change down? Or do you control with the brake and use neutral?



Not talking mountain grades, but normal everyday driving.

[Eye of the Tiger]

I like to downshit and floor it.

[Cookie Monster]

Gear down.

I keep reading that modern engines shut off fuel if coasting in gear down hills since the wheels/transmission keep the engine spinning. I haven't noticed an increase/decrease in mpg's really so I can't tell what it's doing, but I shift down and don't use the brakes.

This also means that when I occasionally drive automatics, I go like twice the speed limit down hills because I keep forgetting to use the brakes.

[The Pirate]

There is little (or no) difference in economy when idling vs. coasting in gear in most modern engines.

I downshift pretty regularly.  Almost always when coming off of the highway, and usually when I'm coasting to a red light.   Plus, you're always in the proper gear to motor out of situations that may arise.

[giant_mtb]

I just about always downshift and coast, at least for one gear down.  No need for the wear 'n' tear on the brakes if it isn't totally necessary.  Plus, what if the light you're approaching (assuming it's a light at the bottom of the hill or whatever) turns green again?  If you're neutral, you hafta slip back into gear and start back up.  If you just downshift a gear, you're all set to accelerate back up to speed.

Shifting to neutral right away is just lazy.

[93JC]

[Laconian]

The car is being slowed down because the closed throttle is hard to suck air through, which creates the resistance.

[Rupert]

If it was still combusting lots of fuel, you'd speed up!

It depends on the situation. Obviously, on long grades on the highway, or super-steep mountain/gravel roads, I gear down in any car, but in town, eh, probably not. If there's a red light at the bottom, I probably will downshift. I think on a lot of hills, you start from a stop at the top, in which case, you can just not shift up. Also, it depends on how lazy I am (though I don't see the point in neutral).

[Rupert]

I just about always downshift and coast, at least for one gear down.  No need for the wear 'n' tear on the brakes if it isn't totally necessary.  Plus, what if the light you're approaching (assuming it's a light at the bottom of the hill or whatever) turns green again?  If you're neutral, you hafta slip back into gear and start back up.  If you just downshift a gear, you're all set to accelerate back up to speed.

Shifting to neutral right away is just lazy.

Yeah... Brake jobs are waaaay cheaper than a new clutch.

[giant_mtb]

Yeah... Brake jobs are waaaay cheaper than a new clutch.

Snarky Mc. SnarkSnark over here.

[Cookie Monster]

Yeah... Brake jobs are waaaay cheaper than a new clutch.

Yeah but you're not wearing down the clutch with one downshift as much as you'd wear down the brakes down a hill...

[Laconian]

How depressing would it be if your car billed you every time you pushed the clutch or used the brakes?

ANGRY DOWNSHIFT: $1.25
PANIC STOP: $3

[SVT666]

If you rev match you won't wear the clutch anyway.  Always downshift.  Putting it in neutral gives you less control if you find yourself in a situation where you suddenly need throttle and you're not in gear.

[Cookie Monster]

Plus putting it in neutral means using the clutch. And then putting the car back into gear means using the clutch again.

So technically you're wearing out your clutch even more, and also wearing out your brakes.

[Cookie Monster]

How depressing would it be if your car billed you every time you pushed the clutch or used the brakes?

ANGRY DOWNSHIFT: $1.25
PANIC STOP: $3

[Laconian]

Plus putting it in neutral means using the clutch. And then putting the car back into gear means using the clutch again.

So technically you're wearing out your clutch even more, and also wearing out your brakes.

The speed differential between the friction surfaces is what eats the clutch, not just engaging/disengaging (though that can wear out the bearings?)

[Cookie Monster]

The speed differential between the friction surfaces is what eats the clutch, not just engaging/disengaging (though that can wear out the bearings?)

Doesn't the clutch wear out when it recontacts the flywheel when you let the clutch out?

Or does that not matter if you're shifting into neutral?

[Rupert]

Yeah but you're not wearing down the clutch with one downshift as much as you'd wear down the brakes down a hill...

How much are new pads? How many miles between pads changes do you save by making it a point not to brake? You might save yourself a single brake job over the life of the car.

I'm not saying never to downshift (obviously), but the reasons to downshift are never ever ever to save brake wear (unless you count brake fade as brake wear). When I'm going down a long steep mountain grade (i.e. prime downshift territory), it's for control and laziness (less braking-accelerating-braking-etc).

[Rupert]

Plus putting it in neutral means using the clutch. And then putting the car back into gear means using the clutch again.

So technically you're wearing out your clutch even more, and also wearing out your brakes.

Not necessarily; I pop it in neutral all the time without the clutch. Just wait for the engine speed to approach neutral, and it's no problem.

Anyway, my main argument is actually not that brake wear is worse than clutch wear, it's that wear is wear, and if you don't want to wear out the wear parts on your car, you should just not drive it.

[Rupert]

If you rev match you won't wear the clutch anyway.  Always downshift.  Putting it in neutral gives you less control if you find yourself in a situation where you suddenly need throttle and you're not in gear.

Yeah, but rev matching is, like, extra effort.

[SVT666]

Yeah, but rev matching is, like, extra effort.

It's second nature to me now.  I don't even think about it, I just do it.  I drive my car really hard and at 87,000 miles it's still on the original clutch with no signs of wearing out.  If you know how to use the clutch properly (even driving it hard) you can save your clutch.

[the Teuton]

I pop it in neutral...because I can. That's how the little Mexican guy at the BMW dealer taught me to do it.

[Rupert]

It's second nature to me now.  I don't even think about it, I just do it.  I drive my car really hard and at 87,000 miles it's still on the original clutch with no signs of wearing out.  If you know how to use the clutch properly (even driving it hard) you can save your clutch.

Yeah, I'm 90% sure that the Explorer and Porsche are both on their original clutches at 140 kmiles and 100 kmiles, respectively.

[Colonel Cadillac]

Geeze, you guys are so proactive about hills. A 5 to 4 shift will slow me down a fair amount and I don't normally need that kind of braking. I just go faster down hills.

I guess it really depends what type of hill you're talking about. If I'm driving around New England and enjoying the magnificent, sweeping 50 MPH roads--so between 50 and 75 MPH driving--I can just stay in 4th and be golden. In that type of driving, I'm enjoying a great part of my powerband and there's no need to downshift--plenty of engine braking and lots of power. 5th's really strong here also if I'm driving less aggressively. There's not too much need to shift around, but it's obviously a lot more fun to shift around.

[MX793]

Coasting in neutral or with the clutch is oftentimes illegal (not that it's an easy thing for a cop to spot and then ticket you for).  I try to keep the car with the clutch engaged and the transmission in gear as much as possible not only because it's illegal to coast with the transmission disengaged but because it's much safer to have the car in gear (and in an appropriate gear for the speed) and the transmission engaged.

Many engines shut down the injectors when the engine is under a high enough braking load and the throttle is closed, which reduces the fuel consumption compared to just idling.  So there is some truth to the fuel economy argument.  But to me, this is secondary to the reason I posted above.

[giant_mtb]

Not necessarily; I pop it in neutral all the time without the clutch. Just wait for the engine speed to approach neutral, and it's no problem.

Anyway, my main argument is actually not that brake wear is worse than clutch wear, it's that wear is wear, and if you don't want to wear out the wear parts on your car, you should just not drive it.

Valid point.

[giant_mtb]

Yeah, but rev matching is, like, extra effort.

But it's soooooo much more fun.

[sportyaccordy]

I downshift even in an automatic.

And you don't use any more fuel when you're engine braking. (At least not in a carbureted engine, but I'm assuming it'd be about the same in a F/I engine) The throttle pedal controls how much gas you're using. If you don't touch it, you're not using any more gas than at idle. That's why it slows the car down, it wants to return to idle since that's all the gas it's getting.

I am pretty sure modern EFI engines completely cut fuel & just operate on the car's momentum (in stickshift cars anyway).

[TBR]

If it's a for serious hill then definitely down shift. In normal driving I keep it top gear as long as I can then clutch in to down change if the light turns or to put it in neutral if stopped.

[Submariner]

I like to downshit and floor it.

Which is pretty similar to engaging the e-brake and throwing it into reverse on most other cars.