I never downshift. Is this actually bad?

Page 3 - Seeking answers? Join the AnandTech community: where nearly half-a-million members share solutions and discuss the latest tech.

DVad3r

Diamond Member
Jan 3, 2005
5,340
3
81
Lol @ the no downshifting, you sir are a fat headed driver. Whatever you do don't drive a commercial truck, thx :)
 

LTC8K6

Lifer
Mar 10, 2004
28,520
1,575
126
Yeah, you will downshift coming down hills or mountains...
If you refuse to, let us all know so we don't get in front of you...

Why have a manual if you aren't going to downshift? :D
 

AMCRambler

Diamond Member
Jan 23, 2001
7,706
28
91
You need to ask yourself, WWTSD?

What would The Stig do?

Asnwer: He'd downshift the crap outta that pig till flames shot from the gearbox.
 

jRaskell

Member
Feb 6, 2006
74
0
0
The clutch is only getting worn during the brief periods when it's being engaged. When it's fully engaged, there is no slippage and no measurable wear.

The brake pads are getting worn the entire time they are applied, up until the vehicle comes to a complete stop.

Given that the tires are the only portion of the vehicle actually in contact with the road, I never cheap out on tires. People can argue the supposed minimal gains a high end tire has over the cheapos, but those differences ARE measurable and I have been in situations where an accident was avoidable by very small margins, less than a foot in several instances.

What's that got to do with this thread? Brakes fall into the same category. I don't buy cheap brake components. I also NEVER get rotors turned. It still costs me more to replace a clutch, but the difference isn't that big. Even with downshifting, my clutch still lasts substantially longer than my brakes. Over almost 18 years of driving now, across 5 different vehicles, there's no doubt I've spent far more on pads/rotors and occasionally calipers than I have on clutches. Not once have I had to replace a transmission.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
Originally posted by: DivideBYZero
Worrying about clutch wear due to downshifts is like taking less corners to reduce steering rack wear.

LOL, nice. I like that.

And I agree.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
Originally posted by: Knavish
Road & Track (magazine, duh!) gets this question pretty often, and publishes the answer in the Q&A section. They basically say:

Downshifting was recommended in the past because cars' brakes were pretty poor performing and unreliable. (I think the "past" means the pre-disk brake era, espeically pre 1970s) Currently brakes work very well, so downshifting is *not* worth the extra wear on your transmission and clutch.

...and downshifting absolutely does not save gas.
Of course it does.

 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
What I do in my Civic is just let the current gear bottom out if I want to slow down using the engine. Then I just pop it into neutral once I hit 1k rpms. I rarely will pop it into 3rd to help decelerate from highway speeds if I'm exiting the freeway onto a twisty ramp.

Letting the car decelerate while in gear will save a tiny bit of gas because the motor will not use any gas so long as the revs are over 1k; there will only be air in the engine at that point.

I've managed to get close to 800kms on a tank of gas in my Civic while city driving by using some moderate hypermiling techniques. I don't do it anymore to save wear on my tranny, but when gas prices were sky high I figured it was worth it. I still remember having cruise control activated while going 40km/h in 5th gear. :)
 

Farang

Lifer
Jul 7, 2003
10,913
3
0
Originally posted by: jRaskell
The clutch is only getting worn during the brief periods when it's being engaged. When it's fully engaged, there is no slippage and no measurable wear.

The brake pads are getting worn the entire time they are applied, up until the vehicle comes to a complete stop.

Given that the tires are the only portion of the vehicle actually in contact with the road, I never cheap out on tires. People can argue the supposed minimal gains a high end tire has over the cheapos, but those differences ARE measurable and I have been in situations where an accident was avoidable by very small margins, less than a foot in several instances.

What's that got to do with this thread? Brakes fall into the same category. I don't buy cheap brake components. I also NEVER get rotors turned. It still costs me more to replace a clutch, but the difference isn't that big. Even with downshifting, my clutch still lasts substantially longer than my brakes. Over almost 18 years of driving now, across 5 different vehicles, there's no doubt I've spent far more on pads/rotors and occasionally calipers than I have on clutches. Not once have I had to replace a transmission.

What if you don't think about it just in terms of the transmission? When you use the engine to brake you are putting a similar type of wear on the engine as when you accelerate. So someone who uses the engine to brake all of the time is consistently using some percentage more of their engine's life while driving, while someone who lets it idle and uses the brake does not place the same amount of stress on the engine per mile.
 

jRaskell

Member
Feb 6, 2006
74
0
0
Originally posted by: Farang
Originally posted by: jRaskell
The clutch is only getting worn during the brief periods when it's being engaged. When it's fully engaged, there is no slippage and no measurable wear.

The brake pads are getting worn the entire time they are applied, up until the vehicle comes to a complete stop.

Given that the tires are the only portion of the vehicle actually in contact with the road, I never cheap out on tires. People can argue the supposed minimal gains a high end tire has over the cheapos, but those differences ARE measurable and I have been in situations where an accident was avoidable by very small margins, less than a foot in several instances.

What's that got to do with this thread? Brakes fall into the same category. I don't buy cheap brake components. I also NEVER get rotors turned. It still costs me more to replace a clutch, but the difference isn't that big. Even with downshifting, my clutch still lasts substantially longer than my brakes. Over almost 18 years of driving now, across 5 different vehicles, there's no doubt I've spent far more on pads/rotors and occasionally calipers than I have on clutches. Not once have I had to replace a transmission.

What if you don't think about it just in terms of the transmission? When you use the engine to brake you are putting a similar type of wear on the engine as when you accelerate. So someone who uses the engine to brake all of the time is consistently using some percentage more of their engine's life while driving, while someone who lets it idle and uses the brake does not place the same amount of stress on the engine per mile.

Even in extreme conditions, I don't believe the wear from downshifting even comes close to the wear from acceleration. Under everyday street driving, I'm absolutely sure the two aren't close.

Regardless, I've also never had any engine related problems that could even remotely be attributed to downshifting. I've had to replace the occasional alternator, starter, ignition component, emissions equipment, etc, but the engines themselves have all run just as well as the transmissions sitting behind them.

Also take note that I'm talking about downshifting here. For the most part, I don't engine brake, whatever reduction in speed that comes about from the act of downshifting on my part is purely coincidental (and largely minimized with rev-matching). I use the brakes to stop the car. I downshift so that I am always in whatever gear I'd want to be in should I suddenly want to accelerate for any reason.
 

Farang

Lifer
Jul 7, 2003
10,913
3
0
alright then.. just looking for more insight on your reasoning. I'm not an expert just an interested observer :p
 

spidey07

No Lifer
Aug 4, 2000
65,469
5
76
Originally posted by: Farang
alright then.. just looking for more insight on your reasoning. I'm not an expert just an interested observer :p

The motor is always working. Compression is how it works. Acceleration/deceleration/idling it is always working with compression.

Just to throw a wrench to the discussion I'm at 170K miles on my original clutch and it's still perfectly fine. Had to get a full new set of brakes however. Proper downshifting is not bad for your clutch or your car and has the same wear as an upshift, if not less.

Just be in the correct gear, rev match and your clutch should outlast your car.