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thank you for taking the time to explain this to me!

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To: ev_update@...
From: ev_update@...
Date: Mon, 22 Jun 2015 16:33:24 -0600
Subject: Re: [ev_update] "overdrive"

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"Overdrive" is a gear ratio that is designed to run an engine at a lower RPM at highway speed to save on fuel and make less noise.

It's a ratio that is less than a 1:1 direct connection from engine to axle. Technically the engine is over-geared at this point and can't technically reach its maximum top speed.?

In most common cars the only overdrive gear is the highest gear while the 1:1 ratio is direct below it. In a 5 speed over drive is 5th and 4th is 1:1, in a 4 speed like the Eurovan auto the overdrive is 4th and the 1:1 gear is 3rd

The auto gear ratios are 1st 2.71, 2nd 1.55, 3rd 1.00, 4th 0.68

Notice the 1.00 ratio and the <1.00 top rear (overdrive)

Now, some modern cars with 8-9 speed transmissions have 2 over drive gears above the 1.00 ratio.?

Cole

On Jun 22, 2015, at 12:07 PM, gpatterson53@... [ev_update] <ev_update@...> wrote:

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can someone tell me what people are referring to when they say they are in "overdrive"??