Help understanding gear ratios..

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Aug 11, 2010 | 10:36 AM

1991Jeep_Man

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Joined: Oct 2009

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From: Fauquier County, Virginia

Year: 1991

Model: Cherokee

Engine: I-6 4.0 HO

Help understanding gear ratios..

Call me an idiot, but I just wanted some help to make sure I understand gear ratios properly.

For example, I have read the the AW4 auto transmission has gear ratios as follows:

(1st) - 2.80
(2nd) - 1.53
(3rd) - 1.00
(OD) - .75

Do these numbers represent how many turns the engine crankshaft makes before the output of the tranny turns?

Like, for first gear. The engine turns 2.8 times when the tranny turns once?

Thanks for the lesson. And dont think me too stupid lol

Aug 11, 2010 | 10:40 AM

Donnie_K

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From: Columbus, Ohio

Year: 1997

Model: Cherokee

Engine: 4.0, comp cam, 99 intake, apn header, neon injectors, Thunderbolt 2.5" High Flow Cat

yes, that's what it means. then for your rear end or final drive ratio, if you have 3.55 gears it's 3.55 turns of the tranny output shaft/driveshaft for every 1 turn of the wheels.

Aug 11, 2010 | 11:33 AM

2000sport

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Joined: Oct 2009

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Model: Cherokee

Quote:

Originally Posted by Donnie_K

yes, that's what it means. then for your rear end or final drive ratio, if you have 3.55 gears it's 3.55 turns of the tranny output shaft/driveshaft for every 1 turn of the wheels.

gotta love short and simple! ty also!