TOM: You're right that the engine and transmission really couldn't care less when you downshift, but what you don't realize is that the clutch really suffers. RAY: So, Mike, as much as we hate to do this in so public a forum, we're going to have print right here in the newspaper that your wife seems to know more about driving than you do.
We realize that your pride and reputation were both on the line when you sent in this question, and that because of our answer, you'll probably be saying a lot more "yes, dears" than you would have liked over the next twenty to thirty years, but that's the risk you take when you go public with something like this, Mike. TOM: When approaching a red light, the first thing you should do is step on the brakes.
It could shake, rattle, or emit a low rumble, and it could even sound like the vehicle is about to stall. The tachometer can also inform you when it's time to shift down if it reads about 1 or 1, RPM. Without looking at the tachometer, How do you know when to downshift? You'll probably check the tachometer a lot when you first start driving a manual transmission, but as you get better at it, you'll learn how the vehicle feels when the gear is too low and won't need to.
The low, rattling sound and stuttering feel of an engine lagging in a too-high gear will become familiar to you. The tachometer indicates when it's time to change gears. There are 3 ways to downshift with a manual transmission:. Now that we have already discussed the benefits of downshifting and how to do it right, let us step back a little and know the instances when you should avoid downshifting or engine braking. Here are the instances it can be.
As mentioned earlier, downshifting, also known as engine braking, is a helpful technique for reducing brake wear, maintaining vehicle stability, and safely descending hills.
It's a common feature of manual transmissions. It can be used with automatic transmissions , but it has a lesser impact. However, caution should be exercised in using engine braking too forcefully. As the vehicle slows down, a driver will normally change from a high gear to a lower gear to fully use engine braking.
This procedure improves the technique's efficacy. But shifting at too high an engine speed RPMs or going into too low a gear, on the other hand, can put a lot of strain on the drivetrain, especially the clutch and transmission.
Premature engine wear can also be caused by too much applied force from a sudden dramatic change. This is what other experts are worried about. So when coming to a halt, do yourself and your wallet a favor by using the brakes and never downshifting past 2nd gear. Yes, when you're doing it to the extreme. Allowing plenty of space on the road ahead for a safe, assured stopping distance is also important.
Engine braking is beneficial because it reduces brake system wear, improves fuel economy, and improves vehicle stability. This will rest the clutch plate diaphragm, the release bearing, and your left foot. When proceeding down steep hills, as with an automatic transmission, it's always a good idea to downshift and keep the vehicle at a desired speed with the use of "engine braking", as opposed to the brakes themselves.
Riding the brakes on a downgrade for long periods of time will overheat the brakes and cause brake fade, which can be dangerous. When slowing to a normal stop, downshifting is really a personal preference, and it is fairly safe staying in neutral and simply using the brakes. And i'm going to make the left-hand turn here and I'm going uphill here so I can just use the hill to slow down. You can see that the wheels are spinning in second gear - so as soon as I shift the third it gets traction again.
And I get off here and the road is not plowed and I put it back into third gear to get more traction. Again I'm staying near the center of the road because there's people walking around shovelling their driveways and those types of things. I'm going slow and travelling 40 kilometers an hour less than 40 kilometers an hour which for you in the states would be about 20 miles an hour.
I shift quickly into second because I'm going to get more traction; even with my steel studded snow tires on the truck. No vehicles coming, and again the rear end starts to kick around because the tires are spinning as I'm in second gear. Now I'm going to get up here and I'm going to get on a bit of a slippery section and I'm going to show you that downshifting will potentially cause you to do damage to the drivetrain over a long period of time.
That you're going to do undo damage to the drivetrain and eventually what you're going to end up doing is you're getting up changing out the clutch, which any of you have had to do a clutch job, you know that it's anywhere from a thousand to five thousand dollars to change out the clutch.
You saw that it revved down quite a bit there on the tachometer - I just kept my foot on the throttle and the engine climbed back up by itself because it's in third gear. And I just shift to fourth gear there and actually I'm doing 50 kilometers an hour and i'm going to show you how to do this.
And I'm going to to skip here - I'm actually going to go down to second gear and I'll show you this. And one of my pet peeves is over revving the engine, so there's really no need for you to have in third gear here.
And now I'm just kind of working the steering wheel to go around this corner on the slippery conditions here. And I'm just keeping my foot off the throttle and you can see it's revving up and I am using the engine braking to go down that hill a little bit. I'm not actually shifting down or shifting up and because you're on compromised conditions, I just want to use gentle, easy, very subtle touches on the controls.
Because in compromised conditions like this, when it's slippery you don't want to brake and steer at the same time. You want to have the vehicle in the gear that you need to go around the corner before you start turning the steering wheel.
Because if you're trying to steer and shift and brake all at the same time, especially in the wintertime as it is right now, you are probably going to end up going straight through the intersection. It comes right down and I'm in second gear and I can just go around the corner And again, on a manual transmission, the equation for fuel economy is the highest gear for the lowest rev. So the faster you can move through the gears when you're accelerating, the better fuel economy you're going to get.
Because you're going to be able to get into your tallest gear more quickly, and you're going to bring your revs down and you're going to get better fuel mileage. You're going to get better fuel economy because the engine is not working as hard and it's going faster. So you want to try and move through the gears as quickly as possible, and that's regardless of whether you're driving a five-speed, six speed, or driving a 9, 10, 13, 18, or 15 speed.
That equation works for all manual transmissions: the highest gear for the lowest rev - it's that simple. And for those truck drivers and professional drivers watching this video, there are companies that do pay you a fuel bonus.
So if you work through the gears faster, you're going to make more money because you're going to get that fuel bonus. So I'm going downhill here you can see i'm just using the brakes and I'm not changing any gears or pushing the clutch in.
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