Is it normal to lost power when shifting into "overdrive"?

Dear Car Talk

Dear Car Talk | Apr 01, 1998

Dear Tom and Ray:

I have a question about my husband's 1995 Ford Ranger. The Ranger has a standard
transmission and a four-cylinder engine. When we put the Ranger into Overdrive,
the rpm goes down but the engine loses power. In order to climb a small hill, we
must downshift to fourth gear. Is this normal? My old five-speed Honda wasn't
like that. Can you explain this to me? -- Denise

RAY: It's absolutely normal, Denise. Especially when you have an engine that is
-- in purely technical lingo -- a real dog.

TOM: My brother doesn't mean that in a bad way, Denise. He just means that this
particular four-cylinder engine is a little on the small side for this
particular pickup truck.

RAY: It's also possible that it's geared differently from the Honda, and the
Ranger's fifth gear is "taller," meaning it slows the engine more to conserve
fuel at the expense of power.

TOM: Whatever the combination of reasons, when you get to a hill, you need the
added mechanical advantage of a lower gear to get up it. And there's nothing
wrong with that. That's why they give you five different gears to choose from.

RAY: Your Honda, on the other hand, may have had a similarly sized engine, but
it probably weighed 1,000 pounds less! That gave it a higher horsepower-to-
weight ratio (more horsepower for every pound of car the engine was pushing).
But if you got to a steep-enough hill with the Honda, I'm sure you would have
had to downshift, too.

TOM: So not to worry, Denise. This is exactly what Overdrive is supposed to do.
It's supposed to reduce the engine speed (and save gas) when you're cruising on
the highway and don't need as much power.

RAY: And also give those six-cylinder Ranger owners a chance to pass you on
hills and feel good about the extra money they blew on their bigger engines.

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