Today: Tom and Ray mediate a marital-manual shifting dispute.
Please save me from the brutal verbal badgering I must endure every time my husband rides with me. We have a manual transmission. Sometime during my lifetime I developed what I perceive a harmless, if not helpful, habit. As I approach slower-moving traffic or a red light, I push in on the clutch and begin to brake. When my speed gets down to, say, where it would be in fourth gear, I put the car into fourth but don't release the clutch. I do that all the way down the gears, never releasing the clutch unless traffic starts to move, at which time I am in the proper gear and simply let out on the clutch, and voila -- I am in the right gear for my speed. My husband insists that this is "down gearing" and that I am wearing out the transmission linkage or gear shifter or something. I know it's not "down gearing" since I don't actually use the lower gear to slow down. But really, am I causing enough wear on the transmission in any way that would require maintenance sooner than the way he does it -- which is to push in the clutch, leave it in until he knows what gear he wants and then move directly to that gear? My contention is that if there is an impact, it is so minimal that the car would be a rust bucket before the added "wear" would affect anything. A lot is riding on this. If I am right, I get to say "Tom and Ray say it's OK" every time I get into the car with him. But if I'm wrong, I have to do it his way. -- Suzanne
TOM: The answer is, It hardly matters, Suzanne. While neither of you is doing it exactly as we would recommend, both of your methods are fine.
RAY: Neither of you is technically "downshifting," because downshifting occurs only when you let out the clutch in a lower gear. When you downshift to slow the car for a red light, for instance, that does wear out your clutch disc -- the most expensive and most rapidly used-up part of the clutch. But that's not an issue for you guys. So you're both off the hook.
TOM: Technically, by pushing in the clutch and holding it in, you are putting a little bit of extra wear on the "throw out" bearing, which is involved in engaging and disengaging the clutch. But in most cars, that lasts for the life of the car anyway, or certainly longer than the clutch disc. The same is true for the shifter linkage and synchros, or anything else you might be using a little bit by driving your way. So I wouldn't even worry about it. Like you said, Suzanne, your car will be on my brother's shopping list (it'll be a heap) by the time any of this stuff matters.
RAY: But if you both wanted to be exactly correct, what you would do is NOT shift out of gear. If you were in fourth gear, for instance, and a light up ahead turned red, you'd take your foot off the accelerator and brake if necessary, and just slow down while still in fourth gear.
TOM: When you slowed the engine down to 1,500 or 1,000 rpm, before the car started bucking or protesting, THEN you'd push in the clutch, put the shifter in Neutral, let out the clutch, and come to a stop with the clutch still out -- and leave it out until it's time to go again.
RAY: Or if, instead, the light turned green anytime while you were slowing down, you'd just shift into the appropriate gear then, let the clutch out and keep going.
TOM: So now, if you so desire, you can verbally badger your husband for not doing it the right way either, Suzanne. Or you guys can have peace talks and create a demilitarized zone on the console between the front seats.