What's Best? Downshifting or coasting in neutral and using brakes?
 

Just a little question on which way is the best to go. How much wear and tear does downshifting cause on the engine? It's always easier to replace the brakes than to repair the engine/tranny. How much gas are you saving by coasting? Thanks for your input.

Rog

You should never really coast in neutral (I'm talking more than just keeping your foot on the clutch when coming to a stop). In fact in some places it is illegal!

I personally down shift because I feel I have more control of the car. However, with brakes these days you are better to probably use the brakes and change the pads.

I think he's talking about when coming to a stop. Put it in neutral and use the brakes. Sometimes you want to shift down though like in traffic, it all depends on the situation. And the gas you might save you would never even be able to calculate it's so minimal.

I think you answered your own question.

if if comes down to a brake job versus the clutch job, you did answer your own question.

Downshifting. It's called Compression Braking, and it's healthier all the way around. Engines hate idling more than anything else, and brakes will quickly glaze if you regularly apply them for more than a few seconds at a time. Other benefits include much quicker throttle response if you should unexpectedly need it, and less carbon build-up in the combustion chambers.

Take care,
-Chris

I usually downshift when slowing or stopping. Secret to reduced clutch wear is to be able to down shift and have engine at proper RPM so as not to slip clutch.

My '89 has 72k on the original brakes and clutch. At last brake check, looks like I'll probably get 100k on them. I plan my stops way ahead so as not to have to stand on the brakes, and have plenty of time to downshift.

Downshifting vs braking
 

Downshifting is fine when done as described above and the RPM's are kept at a constant level.
It's the harsh jerking when you downshift too quickly with the RPM's up high that's obviously bad for both transmission and clutch.

When coming to a stop, especially off the highway, I generally just stay in fourth or fifth gear, then downshift as the car slows or if traffic makes it necessary to slow down sooner, I'll downshift and finally brake as the car slows to around 20 or so. Works fine and I've only had one clutch replacement in 114,000 miles (at 87,000 - and I could have gotten another 5,000 out of it).

Using the brakes normally won't cause overly rapid wear; it's slamming them on at high speeds or riding them unnecessarily that kills pads - which are a replacement item anyway.

Given the choice I would much rather replace brake pads than a clutch unit but if you use both clutch and brake reasonably, both should last a long time.

UPS trains its employees to engine brake(downshift).

I always downshift when driving a manual, you have better control of the vehicle as well. I let the car slow down then downshift but I never down shift to 1st. In otherwords, I agree with PKRWUD.

I disagree. Driving a heavy UPS truck loaded with packages is one thing, driving a lightweight mustang around is something completely different.

In the case of the latter, there is no reason to put extra wear and tear on your cluth and engine when your brakes will do the job just fine.

What extra wear and tear is there?? There is none if you just downshift and don't ride the clutch.

You and I are not going to agree on this one..

Im going to agree with Mr 5.0 on the use of both downshifting and the use of the breaks. That's what i've been doing, i usually don't let it get up more than 2000 rpms when i downshift, then i use the breaks when necessary. I also like the point that you have more control of the car.

Rog

You know, I was paying attention how I come to a stop or when I get ready to turn, and I downshift. But everytime this topic comes up I picture someone going like 65, and throwing it in 2nd to slow down, instead of applyng the brakes. I use both, but I don't abuse it when I shift down.

I have noticed i downshift too much, and also heard the t-5 doesnt like to be dowshifted frequently, i have done lots of drop down to 3rd on the highway races, well i dont do that anymore, my tranny started whining, then eventually the cluster shaft went south, im trying my best to keep this one alive, but now my brakes feel like they are going to the floor, but like mentioned before, its a replacement item anyway, the t-5 is much more costly and harder to install.

I would think every time you shift to another gear, you are dis-engaging and re-engaging the clutch, which would cause some wear on the friction material. You are putting extra wear on the throw-out bearing, more applications of the pressure plate, etc...

And if you downshift to the point that your engine RPM's increase (which would be the only time you are using "compression braking" in the first place) you are increasing wear on your engine by increasing the rpm's every time you stop.

If you wait to downshift that you are going so slow that engine speed does not increase, what was the point in downshifting in the first place? You accomplish absolutely nothing.

me opinion is that if you are in traffic and traffic just slows down then i think downshifting is ok. But say if you are driving and you see the light is red and you are going to have to come to a complete stop then i think you should use the brakes. Come on guys brake pads cost what $25 to $40, no comparison. And i think someone asked Bernie in MM&FF and he stated that the T5 puts up with alot of abuse with acceleration why put it through more by decelerating.

Hey guys, my project is done so I may now participate once again. :)

I guess the easy answer that I would give is to not ever put your car in neutral because of the difficulty of having to shift back into gear in the case of an emergency as Chris suggested.

As far as it adding more wear on the clutch, I would say that it doesn't since you HAVE to shift into another gear at some point when slowing down, so why not do it to engine brake.

As far as stresses on the engine go, engine braking in a Mustang couldn't possibly be more stressful than the amount of torque we apply when accelerating. Think about how long it would take to stop by only downshifting from 120 mph vs accelerating to 120 mph.

The problem with engine braking is that the person directly behind you doesn't see brake lights. The benefit is that the cop in front of you doesn't see your nose dive AND the people farther behind you don't see brake lights. I can't stand it when people are constantly tapping their brakes in heavy traffic. It only adds to the congestion.

I don't think I would ever just engine brake coming to a stop. I usually just brake, press in the clutch, and downshift based on what speed I'm traveling at. I always like to be in a gear that I can accelerate. I never shift to first unless I'm at a complete stop.

Mr. 5.0. is absolutely correct that you shouldn't just downshift without matching engine speed.

For automatic tranny people, it is best to leave your tranny in gear and not shift to neutral when sitting at a light.

There, have at me. :)

wow, my editing skills are weak! sorry....

It's okay. At first glance I didn't think you wrote anything, but I figured it out. :)

Yes, I keep the clutch in and row through the gears depending on how much I slow down. If I need to, I just release the clutch and give it gas. Never had a throwout bearing fail on me yet. Once I stop, though, I'll slip it into neutral if I know I will be sitting for a while.

WEll this is proble not the best thing to do but i thought i would throw it in anyway, I like to down shift when coming to a stop just to here my exhaust, but i also like if i have to turn really fast and sharp i like to throw it into 2 doing about 55mph let the clutch out and lock the back tires up and slide the as* end around to complete my turn:) but thats just me acting like a jack ***:)