David_M

I "know" how to drive a stick, but I was driving a honda, and didn't give a crap if I was being hard on it. My new RX-8 will be in my hands this coming Monday, and I wanted to know if anyone has any hints.

My main question is:

I used to shift down when slowing down, and rather than put on the breaks, I'd go from 5th down to 4th, and rev the engine to match the speed, and then left off on the clutch and let the engine slow the car down. Is this bad to do?

fxdsconv2000

The manual says something about that, I can't rember what exactly. I think it says not to do it for a long time (like going down a big hill). I don't think there is anything wrong with down shifting to slow down (auto's do exactly that). Hell I down shift on the highway all the time to pickup speed, like from 6th to 4th or 3rd. I think this would be much harder on the clutch than down shifting to slow down.

Don't worry about it and drive it like you stole it!!!!

Congrats on the 8

shams42

I burned up a clutch that way. (Not in an RX8 though). Use your brakes to slow down -- that's what they're for.

There's nothing wrong with leaving it in a low gear when going down a long grade, but don't run through the gears to slow down.

In the long run it won't hurt too much but it puts unnecessary wear on your clutch.

Matt

David_M

ok, that was exactly what I wanted to know. Unfortunately I'm kinda in the habit of using the lower gear to slow down. Hopefully I can break that habit.. It's been about 7 months since I drove stick

rotarygod

I drive both my Civic and my RX-7 this way. Sure it's a little hard on the transmission. You have to remember that accelerating quickly is far more stress on the drivetrain. At least you are going easier on the brakes.

fxdsconv2000

Here is a quote from the manual. "On a steep downgrade, downshifting helps maintain safe speed and prolongs brake life". So what I rembered was the exact opposite of what the manual says.

How did you burn up a clutch by downshifting? Once the clutch is fully released there is no real wear on the clutch. Just like on non anti-lock brakes once you lock-up the brakes there is no wear on the brake pads, because nothing is moving against them (no friction). When the clutch is fully engaged there is no wear because both the clutch and the flywheel are moving in unison.

Check out this page http://auto.howstuffworks.com/clutch.htm

So when downshifting the clutch would be spining faster than the flywheel until it was fully engaged then they would be in unison. How is this different then the flywheel spining faster until the clutch catches up. This is the same as when you start from a stop or when you change gears while moving. Now if you were to go from 6th into 3rd and feathered the clutch you would be alot of wear on it, but the same thing could be said for upshifting.

I may be wrong, I just don't think the physics are much different between upshifting and downshifting.

chairborneRNGR

okay, youngsters, listen here.

it's called "engine-braking". as long as you're not going TOO fast for the gear you downshift too, it's ok to do. in fact it's (marginally) better to do, for the brakes' sake. if you had learned to drive on stick, you should already have that little technique in your head (though "technique" is an odd term to use for engine-braking...it's not some super-secret thing or anything...it's common knowledge...perhaps driving stick in general is a lost art for generations of kids driving automatics...kinda like how kids love their 4-bangers, and abhor "silly" pushrod v8's...sorry...i digress)

guy above is right, there is absolutely no way to "burn" your clutch by engine-brraking. not unless you're using the clutch wrong (ie you're riding it)...in which case you're burning it up by driving in general...not by downgrades.

David_M

when you say 'riding it', do you mean not letting off the clutch all the way when driving?

fxdsconv2000

Yes, that is riding the clutch.

In that case the clutch never has full pressure on the flywheel so there is some slipping going on. slipping = friction, friction = wear

chairborneRNGR

just take your foot completely off the clutch pedal when you aren't using it. and fully depress it when your moving the stick. the rest is really just getting the feel of it.

there is no wear on the clutch if you're not touching the clutch pedal... you have other problems if you're shifting into 1 at 70mph, but it wont be your clutch.

doc.marx8

i have been driving stick for the last 17 years. It is customary for me to always downshift to assist my braking and slowing the car. In recollection, for the 16 years of owning my 1st rx7 (88 convertible) I've had only 2 brakejobs and im still on the original clutch which works fine. I did realize that i had more routine tuneups (changing the plugs) often earlier then the scheduled reccomendation. Im uncertain but i think downshifting might go through your plugs sooner, but plug replacements were always cheaper than frequent brake jobs. Im not an expert driver of any sort, but a manual just feels better when you assist your braking with downshifting to slow down or maneuver, especially in mountain driving.

happy rotoring

David_M

Note: screen name hijacked

went_postal

If you are worried about your clutch there are really only TWO very big no-nos.

When just crusing around a lot of people like to keep their hands on the shifter. If you do that please slap yourself right now. That is a bad thing and believe it or not you can sometime exert more pressure on the stick than you realize. This pressure can throw things out of alignment and that would be the bad thing.

The other thing that some people do too much is to leave their foot on the clutch pedal while shifting around the gears. Whereas you may not be putting much pressure on the pedal you could still possibly be "riding" the clutch. You will hear about this kinda thing all the time. I think I even read about it here on this board.

Now... I have a question that goes with this. What RPM do you guys cruise at on the 8? I have always had V8 5 speeds so I am not used to where this thing is supposed to ride at. I have been on the highway in 6th gear letting in sit at around 4k/80mph.

Any comments on the RPM thing?

went_postal

Oh... and try driving through the west virginia turnpike and NOT downshift.

My truck has almost 70k miles and it and the original clutch.

My fiero went through two clutches while owned by my father but that is because my father is one of those people that keeps the clutch in at stop lights. Being originally from Chicago... that is a lot of stop lights. I have put about 20k miles on the fiero and the clutch feels like it is brand new.

When downshifting just don't take forever letting the clutch out. But don't pop it either... Unless you REALLY want to chirp the tires.

Has anyone been able to chirp the tires shifting gears in the 8?

My neighbor has a 96 or so Impala SS automatic and that thing can chirp in both second and third. Not good for the tires or tranny but it makes the car seem mean as all h311. =)

DemonRX-8

I have driven two manuals since 1987 - the 8 is the third - and have never had any problems with the clutch. The Escort would still bite great on a hard launch when I traded it and the Probe's clutch still feels strong as new. Knowing how to launch and shift properly will do wonders for your clutch life.

Launching (normal driving) should be accomplished with a quick, smoothe release of the clutch with minimum slipping. Always match revs when you shift - i.e. let them drop on upsifts and blip the throttle on downshifts. Engine braking is not inherently bad for the car, but slipping the clutch to brake is horrendous for the clutch plate. Keep in mind that the friction is applied in the opposite direction that it is normally applied. While I don't think most clutch surfaces are unidirectional, I think it's possible that they could get "bedded" to work well in one direction. If anyone knows differently, please chime in . . .

beachdog

There is one element of downshifting that can potentially cause more wear and tear than upshifting. Just think of it this way. Wen starting from a stop in first gear, you have at most about 150 lbs of torque being supplied by the engine to the clutch and the rest of the drivetrain. When you downshift from say 80mph in 6th gear, the momentum of the car can apply LOTs more than 150 lbs of torque to the drivetrain and clutch. (not an engineer so I can't do the math). More torque = more wear and tear

Drive however you want to.

For me, I use downshifting to keep the transmission in the right gear for what comes next - either more decelerating or back to accelerating. (in fact, I "retrace" on downshifts - go down through the gears sequentially without skipping gears) I use the brakes for braking with only the slighest assist from downshifting. Brakes are cheaper to fix and replace than clutches and transmissions. A philosophy that has served me and my cars well.

went_postal

knowing how to downshift can save your life, take my word for it.

I own an 85 Fiero GT that has been modified from stock. For the most part it sits in the garage and gets dusty. Once in a while I take it out. It was originally my Dad's and he sold it to me for a dollar about 10 years ago.

Well... One day I had it out and I was screwing around on one of the backroads. The car is originally from Chicago and it had seen about two Chicago Winters. Apparently that is enough. =(

I was coming to a point where I needed to stop. As I pressed down on the break pedal I started hearing this hissing sound and the pedal was going down to the floor. Later I found out that I had blown a hard break line.

Anyway... I was doing about 60 or so MPH and I had to stop the car somehow. The E-Brake does not work very well on these cars so the tranny was my best choice.

Working the gears downward saved my life.

I hear that some of the driving schools teach a lot of this stuff.

BIMMER5&RX8

It is simple. Break pads are much cheaper to place compared to the clutch. Use your breaks to slow down.

GiN

I've chirped into 2nd and 3rd with some 8krpm shifts. I've also chirped going from 6th to 4th on a highway. Then I felt kinda guilty for abusing the car like that.

Anyhow, I concur with the notion that engine braking is fine once the clutch is fully engaged; the highest chance for damage occurs while you're downshifting and slipping/dumping the clutch.

I, Claudius

When I learned to drive a stick on a '65 MGB (longer ago than I care to think about) the guy who was teaching me warned about "feathering" the clutch - by which he apparently meant something more subtle than riding the clutch - even touching the pedal unless you mean to shift could increase wear (kind of like keeping your hand on the shift ****, I guess). Has anyone else heard this term? Just curious.

emailists

2 things.

First - for me I live in a large urban building with underground parking 3 floors below street level- the turns are incredidibly tight as they were mis designed by a japanese artichture firm for small japanese cars, and I have to really slow to like 2 MPH to get through these turns without hitting a column. I really feel like like I am killing my clutch with all the feathering needed to get through the turns, but what can I do?

second- I heard that too about not resting your hand on the shifter- but then someone told me recently that for modern cars this is no longer an issue. Can anyone comment?

went_postal

not sure how the issue would go away just because it is a "modern" car.


The explanation that I got was that it puts pressure on the synchros. Since it is still a direct mechanical connection to the tranny I cannot see how that would have changed.

Smoker

Wrong. Same damage will occur. Even on modern cars

I wrote this on the other thread:

pauleta

I thought there was no wear on the clutch when you have your foot off the pedal or if you have the pedal to the floor. Am I mistaken about the second?

Zio

good luck driving it out of the lot