Will my husband save his transmission by shifting to neutral at stop lights?

Aren’t you supposed to slow down in gear even in manual, if it is in Neutral you would have to be burning gas to keep running and DFCO won’t work, correct?

That’s largely offset by the fact that you have to start coasting later because of the engine braking. I coast to red lights in neutral or with the clutch disengaged unless I actually need the engine braking to slow down, which means that I didn’t start coasting soon enough or it is downhill towards the red light.
It’s like a sailboat racing start where the only thing worse than being late to the starting line when the gun goes off is to be there too early and you have to stop and accelerate from a dead stop while the boats that have momentum roll over you and then blanket you with dirty air. I always attempt to have at least a little momentum left over when the light turns green, even walking speed makes the difference between just engaging the clutch on an idling engine and having to do a full stop start with the clutch slipping it entails.
It’s one reason why I never have to replace my clutches in my cars.

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Anytime the clutch pedal is pressed in, even if the engine is just idling, the clutch’s throw-out bearing is spinning. To prolong its life, it’s a good idea to put a manual transmission car in neutral and let the clutch pedal return to its normal position while waiting for a red light. I think most manual owning folks do that anyway b/c it is annoying to have to keep your foot pressed the clutch pedal. And if your foot accidentally slips off the clutch pedal with the transmission in gear, you might jolt ahead very quickly and bang into the car in front of you, or worse, a pedestrian.

I presumed the OP was asking about an automatic, b/c there’s a similar posting on this subject in a recent column by Ray in “Dear Car Talk”.

https://www.cartalk.com/blogs/dear-car-talk/will-putting-car-neutral-stoplight-harm-transmission

So did we all - but OP didn’t tell us. The correct first response is to ask. The husband may also be carrying on a habit he learned on a manual, a valuable thing for the wife to know if she wants him to change his practice.

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I usually coast to a red light (M/T) in the gear I am in (no downshifting) but shift to neutral as I am braking to a stop. I have so far owned over 40 motor vehicles. At least 30 were M/T. I have replaced a total of 2 clutch discs and throw out bearings. Only because the engine and transmission were removed from the vehicle. They were fine as well as the flywheel and pressure plates that were perfect but the discs and bearings were inexpensive so why not?

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The thing is with a MT you have to shift anyway when you come to a stop so it’s really no big deal if you go from high gear to neutral for a minute and then to first again when the light changes (or just before). Otherwise you’ll just go from high to first and sit there and your leg might get tired. At any rate for that reason, I suspect the wife was talking about an automatic because an MT wouldn’t have been causing the same irritation.

I’ve seen it done before VDCdriver, but I never knew where the logic came from, thanks.

When I was a kid, at various times I subscribed to Mechanix Illustrated, Popular Science, and Popular Mechanics. One of those publications ran a monthly column in which renowned race car mechanic Smokey Yunick would provide info and advice. I can remember Smokey advising drivers to put their automatic transmissions into neutral at stop lights in order to lessen the chances of the trans overheating.

Trans overheating was a potential problem in the early days of automatics because many of them relied on “air cooling”, rather than a connection to the engine’s cooling system, and “air cooling” was not very effective–especially when driving at low speed.

Manual transmission: shift into neutral while stopped, it can save wear on the clutch - but it’s probably not doing anything good or bad for the transmission.

Automatic transmission: do not shift into neutral while stopped. If it is an inordinately long stop, such as waiting for a train, then you can shift it into park so you can take your foot off the pedal. But you would never shift into neutral under normal driving conditions with an automatic transmission.

No it won’t. When the clutch pedal is fully depressed there is ZERO wear on the clutch. There is some wear on the throw-out (or thrust) bearing. But no wear on the clutch.

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It depends on what you consider to be “the clutch.” There is no wear on the clutch DISC. But when you have your foot on the clutch pedal, you are engaging and wearing the hydraulics, the throw-out bearing, the clutch fork, and the pressure plate - which are all part of the clutch mechanism.

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Hydraulics - no. Since you have to press the clutch pedal in again when you need to shift.

Clutch Fork - Yes - Maybe. When was the last time you replaced a Fork? They should last hundreds of thousands of miles.

Throw-out bearing - I already stated it is getting added wear, but not much.

Pressure Plate - Yup…a little extra wear. Putting pressure on the springs.

But overall I really don’t think there’s going to be much of a difference one way or the other.

Yeah, probably not a whole lot of difference either way, even with the throw-out bearing. You’re going to replace the clutch disc long before that’s going to go, even if you keep the car in gear while stopping. I think a more substantial argument to put a manual transmission in neutral is the possibility of a fender bender if your foot slips off the clutch. I learned that the hard way (and with a Karmann Ghia that has the nose thing sticking out over the bumper).

Just the fact that holding in the clutch pedal or the clutch lever on a motorcycle is tiresome is reason enough to shift to neutral. Unless you are driving a vehicle that uses a hand operated over-center clutch.

I did not have my foot slip off the clutch pedal. I had a seal blow out in a clutch slave cylinder. Same result.

Red light cameras wouldn’t get you for this. They take 2 pictures (one to capture the driver image front-side, and the second to show proof of illegal act, in this case your car – with plate – mid-intersection during the light’s stop-state) and are triggered based on the state of the light and speed of your vehicle before you got near the line. If you stop at a red light, and then decide to go thru it anyway, the camera won’t know you’ve done so. If you’re going at high speed towards a red light and have good brakes that stop you before getting to the light, the cameras will go off but you won’t be ticketed since the necessary second photo (showing your car in the intersection) won’t be there to prove you blew the light. If you inch (or “foot”) up after stopping normally, neither the first nor second pictures would exist – they’d never know you did anything.

Also remember from driver’s ed that all you need is your front axle to be past the stop-line before the light is red to qualify as having been in the intersection and therefore legal (and in fact required) to pass thru the intersection.

Being realistic, what are the chances of a guy riding shotgun in his wife’s car, and said wife driving a car with manual transmission? My money would be firmly on slim (in the case of a very young couple) to virtually none. Automatic was the clearly obvious assumption to be made here, but the one more likely not made by those driving MT (myself included).

A couple years ago I was trapped in an intersection turning right with a green light onto an uphill approach to a bridge where I could not see the backed up traffic on the bridge. The red light camera did not flash me. A few days ago I finally got a green light at a busy intersection. I looked left and right before proceeding and was treated to red light runners from both directions! What is wrong with these idiots?

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Not in any driver’s ed class I had. Yellow means do not enter and clear it if you are already in. Yellow lights last a fairly long time. You shouldn’t be just entering the intersection when it turns red…

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Don’t enter on yellow is what you should do, but you won’t get a ticket for it, at least not here.