Join the Car Talk Community!

OK guys it's time for both of you to sign...

RSS
Dear Tom and Ray:



OK, guys, it's time for both of you to sign up for Clutch 101 and 102. I just
read your response to "Susan." You told her to leave her transmission in
Neutral and her foot off the clutch pedal when stopped at a light, and you told
her not to rest her foot on the clutch between shifts. Otherwise, you said, she
would be wearing out the clutch-release bearing

Your statements to Susan are all wrong! Most manual transmissions today, and
for the last 10 or 12 years, have a self-adjusting clutch system. To accomplish
this amazing feat, the clutch-release bearing is running all the time no matter
what. Second, the clutch-release bearing today is much larger than necessary.
These clutch-release bearings are designed to go one million cycles (pushing
the pedal down one million times). So people can feel free to leave their foot
on the clutch pedal today at stoplights with no negative repercussions. Now you
may ask, how do I know all this stuff? Well, I sold the bearings to Detroit for
many years. I ate, drank and slept these bearings, and sweated out the OEM test
programs. Are you ready to issue a correction? -- Phil

RAY: Well, not quite yet, Phil. You're right that the vast majority of
brand-new cars are coming off the assembly line with self-adjusting clutches,
but we still see 20 or 30 cars a month in the shop that do require clutch
adjustments. That means there are millions and millions of non-self-adjusting
clutches still on the road, including the one in Susan's car (and a lot of
other Japanese cars sold in the '80s and '90s). And each time she pushes in the
clutch pedal, or rests her foot on the clutch between shifts, she IS wearing
out the clutch-release bearing.

TOM: We're not saying it's the end of the world. In most cases, the clutch disc
wears out first anyway, and when you replace that, you replace the release
bearing at the same time. But if you have a car without a self-adjusting
clutch, you should leave your foot off the clutch pedal when you're not
actually using it to change gears.

RAY: Ten years from now, when the vast majority of cars on the road have
self-adjusting clutches, we may change our blanket recommendation. But because
most people don't even know whether their clutch is self-adjusting or not, we
think the safer route is to recommend that everybody lay off the clutch pedal
when they're not actually changing gears.

TOM: So if you'd be kind enough to make a note in your calendar to call me 10
years from today, Phil, and remind me to make that change, I'd be very
grateful.

RAY: But make sure you call in the afternoon that day. He's got a plumber
coming in the morning.

You must be logged in to leave a comment. Login / Signup
Support for Car Talk is provided by:

Donate Your Car,
Support Your NPR Station

...and get a tax break!

Get Started

Find a Mechanic


Go



Submit