Help understanding gear ratios..

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08-11-2010, 10:36 AM

1991Jeep_Man

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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

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08-11-2010, 10:40 AM

Donnie_K

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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.

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08-11-2010, 11:33 AM

2000sport

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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!