mdp c230k

Does anyone here actually downshift to come to a normal, not emergency, stop? After reading a few threads, it seems like you people are actually downshifting to slow the car down! This is not the way to stop a car! Downshift when you need the power to rip around a turn or pass a slower car, not to stop the car. Just leave the car in the current gear and use the brakes unless there is an emergency. If you downshift you are wasting your clutch and putting lots of pressure on your drivetrain needlessly. Brakes are the most powerful part of the car, they will stop it under most circumstances. They are also much cheaper than a clutch to replace. You will never see a racecar driver downshift for the sole purpose of stopping, they do it to be at the propper rpm if they are slowing down and are going to then accelerate again without stopping. Please, dont waste that clutch and strain the train! Take any high preformance driving class and they will pound this into you.

Rick

Excuse me, but...

I think for starters, you're misinterpresting something. People have posted that they downshift to slow the car before stopping, not downshifting to stop the car. This method not only saves wear on your brakes, but is much less of a dramatic change to the drivetrain in that it gradually slows those components down as well. If anyone were to follow your instructions, their engine would 'chug' at less than 30 mph in 6th gear, not to mention that you'd go through 30,000 miles worth of brakes every 10,000 miles. Case in point, look at the way automatic slush boxes work (enough said?).

Additionally, as a former SCCA superlicense holder, I can unequivocally dispute your comments regarding something you obviously know nothing about.

Race car drivers in SCCA/IMSA/IRL/NASCAR/FIA and yes, even CART are REQUIRED to downshift to slow the car for pit stops. Try shooting through ANY of those pit lanes without slowing and you'd be paying twice your racing salary in fines!

VoyagerDude

Hey, both of you, try being positive

It's Friday!!!!

Boo2

I usually downshift to slow the car, expecially when driving aggressively. Damn, I miss driving a manual!!!

mdp c230k

Rick,
You obviously missed my point. It sounds like people out there are burning up their clutches instead of using brakes, brakes are cheap clutches are not. Only a fool would leave a car in 6th trying to go to a full stop, that was not what I was suggesting. If you are in town tooling around there is no reason to downshift to go from 40mph to stop. The brakes are made to do this just fine without abnormal wear. If you are coming onto pit lane at 120mph, yes, use the engines braking power for a better controlled stop. If you are pulling into the garage at home don't. That is what I'm talking about. If you are ripping around the hills for fun you need to downshift around a turn to get in the propper power band to whip out of it, that is not trying to stop, is it? Being a 'super' driver you should realize that I said don't downshift coming to a normal stop, not don't ever downshift. You also dont have to slam my knowledge or ability because you don't know me. If you did you would qickly appologize. Nuf said?

Boo2

Who are u? Just curious. Tell us so he can apologize!

mdp c230k

I am me. I deserve respect, as do you. No one should slam another unless they know them in person. Who are they to judge someone they have never met? I have no need to prove myself to some one I could care less about, let alone have never even layed eyes on!

zimmer26

I've always downshifted (to slow not stop) my cars for 2 reasons. First it saves brakes, second its fun and lends itself to ambitious driving. Normally when coming on to an off ramp I'll go from 6th to either 4th or 3rd for a modest flap effect to assist in slowing down rather than riding the brakes the entire way. I'm still on my original clutch in my 91 mr2 with 140k miles on it, so I don't see anything wrong with this practice - in my experience anyway. It makes driving a manual worth driving a manual. Would I condone banging every gear and shooting the RPMs to 5 grand to slow down- certainly not.

TimmyC230boy

i always use the auto-shift to slow the car down, not stop it. The way I see it. the transmission is on Mercedes for 5 years and the brakes are on me. I downshift the same as i did in my camaro and it had 75K on it with 1 clutch.

Harris

Is there anyone out there who would downshift to "stop" a car without hitting on the brakes? You'll probably be covering the brakes AS you're downshifting. I drive my C32 like a manual, like Timmy said, the transmission is on MB, I dont see why we've to worry about it.

SoCal240/6

Sorry, but I could not disagree more. That is really a bunch of nonsense. You can downshift to slow a street car down before stopping, but that causes needless wear on the clutch, transmission, driveshaft and related components.

"Gradually slows these components down"??? Wow. That is just so wrong.

A car slowing down is not going to "chug" at 30 mph, in any gear. Even in top gear, when slowing down the car will be just fine until much lower than that. When the speed gets too low, you just take it out of gear and come to a stop.

That is really the undisputed best way to stop a street car, if saving component wear is your goal. Brakes pads are cheap, trans parts are not. (plus, even if you never downshifted once, you would not wear out pads in 10K miles, unless you are doing some extreme driving).

mdp is exactly right.

This has been discussed for years, and there really is almost universal consensus. Try an internet search on the subject.

avlis

First off- I think the topic of this post applied to manual transmissions. The parts negatively affected in downshifting an auto are different than a manny (ie. no clutch).

Please correct me if I'm wrong: I don't have any racing license so bear with me. An automatic doesn't downshift on it's own until the car stops or begins to accelerate again. Unless you tell it to, it stays in the same gear while the car is slowing down. At least this is how the old ones worked. That means the brakes do all the work in stopping the car. The tranny is actually trying to speed the car up once the tranny RPMs drop below engine RPMs right? This being the case- wouldn't the brakes on all cars equipped with automatics last only 10,000 miles?

With that being said...when I exit the highway (or approach a red light) I blip the throttle a bit and pop the stick into neutral with no clutch. It just slips out. Then I use the brakes to slow down or stop. I also coast down some hills if I know I have to stop at the bottom and the engine is still cold (live at the top of a long hill with a light at the bottom). So are you telling me that I'll have to replace the brakes at service "A" (10,000mi)?!

revstriker

Just to add my $.02. I do agree with SoCal on this. It's very easy to wear out your clutch on downshifting to slow down if you don't know what you're doing. Either way, you are putting wear on parts that are more expensive to replace than brake pads. When it comes to slowing down with a manny, I will let the engine slow me down (using the brake as neccessary) until I'm at the lowest end of the gear (normally around 20-25mph for high gear) and then clutch and let the brakes finish. Not saying that this is the only way to do it, but it's always worked for me.

I have never heard of using downshifting to do an emergency stop, except maybe where there is wet or icy conditions, or for some reason, you have no brakes.

shtatc

Just another 2cents....
I do both with my car. Use the brake when I know I will be making a complete stop. But will downshift if I think the light will turn or in making turns where there is no lights. But when I downshift, I use the double clutching technique. Once you know the matched motor speed and transmission revs, it is a very easy technique to use. I guess it comes down to personal preference.

MarkL

Years ago I used to downshift from 5-4-3 when stopping, but now I'm pretty much like revstriker, just let it coast/brake until eventually hitting the clutch and going to neutral.

But here's another question, since we're talking about slowing down. When I'm approaching a turn, I slow in whatever gear I'm in (usually 4th), and engage 2nd, letting the clutch out fully, before I actually make the turn. Is this what most of you do? What I mean is, I don't depress the clutch and hold it, engage 2nd, and let the clutch back out while accelerating out of the turn. So, really, for argument's sake, isn't this the same thing as downshifting for stopping?

Boo2

I feel sorry for your brake pads! Instead of explaining I will just state a fact about the design of the C32 (this is a quote from European Car Magazine's review of the C32):

"During aggressive braking the transmission automatically executes a downshift to the optimum gear. The system uses wheel-speed sensors to calculate nearly instantaneously the longitudinal and lateral acceleration forces.....SpeedShift will automatically select the best (based on speed and pre-stored engine data) for easy overtaking and will engage engine braking on downhills... "

If AMG designed it this way, it's probably the correct way to drive.

TimmyC230boy

When I had my Camaro I wopuld downshift from 6-3 when i went down to 25 mph. I would "always" match revs and blip the throttle. But if an emergency happened i would not hesitate to slam the brakes. But especially if i was slowing from the interstate, just let off the gas and shift ffrom 6-5. then to 4th. No wear on clutch , i had 75K miles plus on it, and no clutch replacement for me. Of course I think i went through a set of brake pads every 7500 miles, but I did auto-X almost every weekend and alot of drag racing at the strip. BUT, if you have the auto in the C230, there is no clutch, so as long as the revs are the same it isnt a problem to shift from 5-4-3-2-1. But you should all know that you STOP with brakes but its easier to slow down with the engine/gears. But hey, do what you want to do! Its your car, you bought it, take care of it, and enjoy it! LONG LIVE MERCEDES!

Iceman's C230

It looks like every one has different driving habits. Allways remember that brakes are cheaper to replace than your clutch. I usually put the car in nuteral before coming to a stop.

Mike T.

I use a combination of both techniques. However, I'd say in my typical driving I downshift maybe 67% of the time when decelerating, using proper double declutching. This is done only when I know I will not be coming to a complete stop, and will have to downshift anyway before re-accelerating.

As for the effects of downshifting on the drivetrain, I've owned 6 cars over the decades and I have NEVER had to replace a clutch component or a synchromesh ring. That is in close to 600,000 miles' driving on 6 cars, all of which were used when I bought them. These cars had as much as 300,000 miles on them. My present one (a 1989 model) has 162,000 miles on it and the original clutch is still better than those on some NEW cars I've test driven.

Mind you, these have all been French cars; maybe German cars' drivetrains are more fragile

mikesbenz

Just adding my 2d (pence, oops showing my age!!) worth

I have always thought that you should always be in the correct gear for road speed and situation, which would only naturally require shifting down, whether slowing for a light, yield, turn or even a stop sign.

I learned and passed my test on a manual in England (33 years ago so things may have changed) and they would, at that time, fail you if you just used your brakes to come to a stop unless it was an emergancy stop.