Dear Car Talk:
I feel compelled to follow up on your column on downshifting through the gears when coming to a stop. You came out against it because you said it wears out the clutch, which is more expensive to replace than the brakes. But I have a BMW Z4 with automatic transmission and paddle shifters. I routinely use the paddle shifters to slow the car down through the gears when approaching a stop. I see no harm to the transmission in using this approach. Your argument about wearing out the clutch does not hold water, as I have no clutch. I feel this is the most appropriate way to slow down the car with no detriment to any mechanical parts. Your comments?
It's a free country, Maurice, and if your pursuit of happiness includes playing with your paddle shifters, it would be unpatriotic of me to interfere. Especially since I have friends who rebuild transmissions for a living and still have kids in college.
Automatic transmissions DO have clutches, Maurice. They're just different kinds of clutches than are used in cars with stick shifts.
They are, however, more likely to last the life of the car than their stick-shift cousins. So what you're doing is a lot less likely to cost you big bucks than if you had a pedal-operated clutch and a stick shift.
Plus, an automatic transmission will downshift "automatically" anyway as you're stopping. It would do it more gently and unnoticeably on its own, with less torque, and less wear and tear. But it is going to downshift itself anyway as you slow down to stop.
Keep in mind that with any mechanical device -- whether it's a transmission or a ballpoint pen -- every time you use it, you bring it one small step closer to oblivion. So making harder downshifts will decrease the life of your transmission a little bit.
But in the big picture, what you're doing is not terribly harmful. Your automatic transmission and its internal clutches should last the life of the vehicle anyway. And if it gives you pleasure, then, by all means, keep doing it. Life is short, Maurice. Paddle away.