To slow a stick-shift car, should you brake or downshift?
27-Feb-1998


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Dear Cecil:

My wife and I are at somewhat of an impasse. We debate (intermittently) whether or not braking a manual-shift car should be done solely with the brakes (meanwhile putting the car into neutral) or by gradually slowing down the car by downshifting--that is, shifting from fifth to fourth to third, etc., and allowing engine compression to slow the car. Which is better for the car? Downshifting and braking, or braking while in neutral? I guess what I am trying to determine is, which will need to be replaced first, the brakes or the clutch? --Gearheads, East Brookfield, Massachusetts

Dear Gearheads:

We have a problem here. On the one hand, the pretty much unanimous opinion of people in the automotive business is that downshifting to slow the car is a completely stupid and pointless practice that increases the risk of a premature (and expensive) clutch job. On the other hand, I always downshift myself. So you have to ask yourself who you're going to believe: (a) the massed weight of expert authority, or (b) those automotive schmucks. I'll merely lay out the facts, and you can decide for yourself.

Among the more vocal exponents of the don't-downshift school are Tom and Ray Magliozzi, hosts of the radio show Car Talk. These guys admit you should downshift when driving down a long hill; otherwise your brakes heat up so much that the brake fluid boils and you lose your ability to stop the car. But on all other occasions, they argue, downshifting does nothing but wear out your clutch faster. A clutch job is expensive; a brake job is cheap by comparison. The proper way to stop is to rely solely on the brakes. Don't put the car into neutral right away, though. Wait till you get down to 10 or 15 miles per hour or just before the engine starts to lug, then throw in the clutch and shift into second in case you need to accelerate. When you come to a full stop, shift into neutral and release the clutch.

Numerous mechanics, auto engineers, and auto buffs echo this view. They say downshifting may have made sense in the 60s and earlier, when many cars had manual drum brakes. These were much less effective than today's power disk brakes and you needed all the help you could get stopping the car. But not any more.

OK, fine. But let's consider the advantages of downshifting:

It's fun. Face it, this is the main reason anybody drives a stick-shift car in the first place, as opposed to an automatic like a normal person. You get to shift gears like Al Unser Jr. and tame a hurtling hunk of steel, even if all you're doing is going to the corner for a box of baby wipes.
You have more control over the vehicle. This is the fallback contention of most downshifters once they realize how feeble the conserve-the-brakes argument is. By downshifting you're always in the appropriate gear for the speed you're traveling. Suppose you were a brakes-only type of guy doing 40 miles per hour in fourth gear. You see a red light ahead and brake down to 20. Suddenly in the rearview mirror you notice a runaway concrete truck bearing down on you. You want to accelerate out of harm's way, but you lose precious time shifting from fourth to second and get creamed. Whereas if you'd been downshifting and were in second already, you could accelerate immediately and plow into the car in front of you. All right, so maybe this isn't the ideal illustration. But you see what I'm getting at.
Besides, we have to ask ourselves, how much harm can downshifting do? Sure, you're putting twice the wear on your throwout bearing and other critical clutch parts. But it's not like they make these things out of plastic. Why, I've been downshifting my Toyota since the day I drove out of the new-car showroom and . . . well, come to think of it, I had to get the clutch rebuilt at 85,000 miles. But everybody knows '87 Corollas had clutch problems.

OK, I'm not claiming I've got an airtight case. Tell you what: I won't hassle you about tapping the top of your Coke can to keep the fizz from exploding, and you don't hassle me about my idiosyncrasies with the clutch.

--CECIL ADAMS

I guess I know how to do it! I got 130K outta my clutch before it needed replacing. And thats doing it 85-90% of every stop I did.
OH, and I got 90K outta the original brakes before they needed replacing.