Engine Braking versus Brake pad Braking

I pulled this from a thread about manumatic tranny... never got a reply and still wondering about different people feel about engine breaking... Namely because I don't want to keep doing it if it hurts my car... but I never really thought it would hurt my car and figured it was one of the perks of having a manual transmission.

goldwing2000 said:

Why would you want to? Any wear you save on the brakes is transferred directly to the drivetrain. Brake pads are a lot cheaper and easier to replace than clutch/transmission components.

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What wear? My impression of engine-braking is that only wear you have is the split second it takes for the clutch to engage a lower gear. After that you just gradually slow down using the engines resistance... thus saving brake pads by using the more stress-tolerant components of the engine that don't really wear down as much.

The engine would still be spinning if you had the clutch pressed down while you use the brakes (at which point you are putting wear on the throw-out bearing), and you'd still be exercising transmission components to put the car in neutral while breaking.

I guess my qualm with that statement is I don't feel that the level of the drivetrains "wearing out" due to laboring against the car's inertia is nearly as high as that of brake pads.

Qualifications/precautions of engine braking:
- I'm assuming you are just shifting reasonably to a lower gear (not dropping it into 2nd when you are going 60 to aid in a panic stop without break pads)
- You're not shifting into first above 10 MPH
- it's always a good idea to still keep you're foot ever-so-slightly on the brake pedal so that you're stop lights turn on and people behind you know you are slowing down... and so that you can slam the brakes on if something silly happens and you need the extra braking power.

i fail to find any good arguments against engine braking, and ive read a crapload about it. most arguments i see are bad logic or hearsay.

so i shall continue to engine brake when i feel like it. as long as you rev match you wont wear out your clutch, and the only thing that would take any wear is the sychros, which wear out anyway with normal upshifting. and if you are worried about your synchos you can always double clutch.

i much prefer downshifting to stops when applicable because it keeps the car in its poweband in case i need to step on it for whatever reason. besides. its fun to downshift.

Well,

PeteyBoy3K said:

I pulled this from a thread about manumatic tranny... never got a reply and still wondering about different people feel about engine breaking... Namely because I don't want to keep doing it if it hurts my car... but I never really thought it would hurt my car and figured it was one of the perks of having a manual transmission.



What wear? My impression of engine-braking is that only wear you have is the split second it takes for the clutch to engage a lower gear. After that you just gradually slow down using the engines resistance... thus saving brake pads by using the more stress-tolerant components of the engine that don't really wear down as much.

The engine would still be spinning if you had the clutch pressed down while you use the brakes (at which point you are putting wear on the throw-out bearing), and you'd still be exercising transmission components to put the car in neutral while breaking.

I guess my qualm with that statement is I don't feel that the level of the drivetrains "wearing out" due to laboring against the car's inertia is nearly as high as that of brake pads.

Qualifications/precautions of engine braking:
- I'm assuming you are just shifting reasonably to a lower gear (not dropping it into 2nd when you are going 60 to aid in a panic stop without break pads)
- You're not shifting into first above 10 MPH
- it's always a good idea to still keep you're foot ever-so-slightly on the brake pedal so that you're stop lights turn on and people behind you know you are slowing down... and so that you can slam the brakes on if something silly happens and you need the extra braking power.

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I have the manusuck tranny and I use the engine to brake the car all the time. I use it in a responsible manor though.. never to bring the motor above 4000 rpm's when using it. I actually perfer to use it when heading into a tight turn as so I can gas it coming out and have the car in the peferable powerband.

good heel-toe practice time...


whatever, I just leave it in whichever gear I'm in and take it out of gear when I reach 1000 rpm. It's a combo of some engine and some brake

Loose said:

I have the manusuck tranny and I use the engine to brake the car all the time. I use it in a responsible manor though.. never to bring the motor above 4000 rpm's when using it. I actually perfer to use it when heading into a tight turn as so I can gas it coming out and have the car in the peferable powerband.

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That's not really engine braking since you're not going into the higher gear to brake the car, but to just power out of the turn better.

Actually...

cbcbd said:

That's not really engine braking since you're not going into the higher gear to brake the car, but to just power out of the turn better.

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It is engine braking b/c you are slowing the car down to enter the turn. Yes, I understand this thread is about bring the car to a stop, but you would be hard pressed to say that "by using the lower gear to enter a turn isn't engine breaking". You just have the added benefit of the lower gear as you exit instead of shifting mid-turn. Just my opinion as is yours....and we all know about opinions.

Tim

Loose said:

It is engine braking b/c you are slowing the car down to enter the turn. Yes, I understand this thread is about bring the car to a stop, but you would be hard pressed to say that "by using the lower gear to enter a turn isn't engine breaking". You just have the added benefit of the lower gear as you exit instead of shifting mid-turn. Just my opinion as is yours....and we all know about opinions.

Tim

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I know what you mean about slowing down to enter a turn. So you are saying that you don't heel-toe into a turn, you just put it in a higher gear and not use the break at all? If that's what you mean, then yes, I agree that it's just purely engine braking

That's it...NO on the heel-toe

cbcbd said:

I know what you mean about slowing down to enter a turn. So you are saying that you don't heel-toe into a turn, you just put it in a higher gear and not use the break at all? If that's what you mean, then yes, I agree that it's just purely engine braking

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That's exactly what I saying... Isn't being on the same sheet of music fun LOL

I am still playing with that heel-toe thing. I went to race-car driving school for the weekend a while back and there is no heel-toe there, so this is what I learned. Once I get the heel-toe thing down I may change, who knows.

The engine would still be spinning if you had the clutch pressed down while you use the brakes (at which point you are putting wear on the throw-out bearing), and you'd still be exercising transmission components to put the car in neutral while breaking.

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The engine would be spinning, but would you rather have an engine spin at 700rpm for an extended period of time, or 4000rpm? Which of the two will be pushing your engine harder, to put it lightly? (Because I'm not qualified to put it technically).

Of course, I'm not a big anti-engine brake proponent, so I'm not going to jump out and say you definitely shouldn't do it. I don't think the relative wear on the engine/drivetrain even over a long period of time would amount to much at all. We're not talking about a lot of drivetrain stress here with a 2.0 or 2.3L 4-banger. At least that's what I tell myself...

so i shall continue to engine brake when i feel like it. as long as you rev match you wont wear out your clutch

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How are you not wearing your clutch? I would have thought it'd be "you're not adding much stress on your transmission if you're rev-matching smoothly enough", but that the friction plate would still wear in the (generally) tiny slip window that's always present in engaging the clutch. Maybe I need to go do some reading though...


I'm a tweener on this issue. I realize that the best place to apply wear in terms of maintenance would be the brake pads, but that doesn't stop me from engine braking altogether.

when i say no wear i mean no accelerated wear. what i meant was i see virtually no difference between a downshift and an upshift in terms of wear/ stress to the drivetrain.

i say that because some people downshift without rev matching and they just either let out the clutch and cause that lurching or they slip it for a long time to get it smooth, both which i believe have undesireable effects.

Will using the engine to assist in braking result in worse gas mileage, and if so, is it much of a difference?

I doubt it, I'm guessing the the throttle will be set to "idle". Thus, the only way to save more gas would be to turn off the car while decelerating (which is prolly very bad).

The only cars I've heard of using gas to reduce the shock of downshifting are the VW TDI's (that way, you don't feel a heavy lurch when you take your foot off the gas in an otherwise very torquey engine)

Yeah, I never did reply to that original post. Sorry about that.

Ok, this is not a flame, a b**** session or a slam on anybody or their driving technique. This is just the way I see it:

If you do a typical run up to, say, 65 mph then it would go something like this:

stop-clutch-1-clutch-2-clutch-3-clutch-4-clutch-5

Now, if you engine brake on the way back down:
5-clutch-4-clutch-3-clutch-2-clutch-1-clutch-stop

If you don't:
5-clutch-1-stop

Fact: Every time you engage and disengage the clutch, you are inflicting wear (agreed, very minimal wear) on the clutch disc, pressure plate, clutch fork, t/o bearing, slave cylinder, master cylinder, pedal bushings and pedal pad.

This is in addition to (as somebody already mentioned) the engine spinning at 2000-4000 rpm instead of 750 rpm. More rpm=more engine wear. (This may cause a very minimal amount of increased fuel consumption but not enough to be noticable.)

Plus more gears inside the tranny spinning, the back sides of the gear teeth being loaded, backlash on the differential and driveshafts and additional reversed loads on the engine mounts (which are already too damn soft).

With the exception of the clutch pedal pad, every single one of those components is more difficult to replace than brake pads. I would rather do 10 sets of brake pads than 1 clutch job.

Also, if you're worried about excessive brake pad wear, you could always begin your decceleration earlier and use parasitic drivetain friction to begin slowing the vehicle and use lighter brake pedal pressure to scrub off the speed at a slower rate.

Now... am I saying that YOU shouldn't use engine braking?
No. Of course not.
All I'm giving is the reasons why I'm not going to do it. As much as I enjoy working on my cars, I enjoy driving them a lot more.
It's your car, do whatever you feel comfortable with!