Does my car have "engine braking"?

Dear Car Talk

Dear Car Talk | Dec 01, 1999

Dear Tom and Ray:

My wife and I have a bet about my 1995 Olds 88 with a four-speed automatic
transmission. When descending a hill, the car picks up speed as if there is no
"engine braking." My wife says this was designed into the transmission; I say
it's a problem of some kind. Who's right? -- Laurence

RAY: Oh, Laurence. We hate to embarrass you right here in front of 270 million of
your fellow Americans -- not to mention our 14 readers in Kuala Lumpur -- but
your wife is 100 percent right about this.

TOM: When you're traveling in high gear (overdrive), there's very, very little
resistance from the compression of the engine. And the transmission is designed
that way so you can, do what? Go fast!

RAY: If you had to overcome significant engine braking while going downhill at 60
mph, we'd all be getting 4 miles per gallon on the highway.

TOM: Wait. What's wrong with 4 miles to the gallon? I wish I was getting four!

RAY: When going downhill, Laurence, you have to specifically take action to get
engine braking. If you're going down a long, steep hill, and you want to use
engine braking to avoid riding the brakes (which is absolutely the right thing to
do), then you have to downshift into Third, Second or even First gear until you
get enough engine braking to keep your speed under control.

TOM: But your wife is right, Laurence. You won't get any real engine braking in
Overdrive, by design. So be a good husband, get those pants up around your chest,
and practice saying, "Yes, dear."

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