maybe a dumb gear ratio question

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Feb 18, 2003 | 05:02 PM

treehugger36

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From: The South

maybe a dumb gear ratio question

I have always been told that you have to have the same Gears up front as you do in back. This sounded odd to me because I could have swarn that I had heard of different gears up front than out back.... most of the time I get laughed at because I am the newbie to the 4x4 world.

am I really that dumb?

I can understand why you might need the same ratio in both places but I am still confused... can someone help me out?

thanks

Feb 18, 2003 | 05:42 PM

Kemicalburns

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From: Bend,OR

maybe a dumb gear ratio question

both axles need to have the same gear ratio or close like a 411's in rear and 410's up front.

Feb 18, 2003 | 06:07 PM

WhëëlMå1

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From: MA

maybe a dumb gear ratio question

Yes, you are correct. There are different gears up front than in back. They are only slightly different tho. For Broncos, in most cases, the rear is 3.55, and the front is 3.54. Theoretically, you would want the same in both axles (if you were to run 4x4 on tar). The reason the front is ever so slightly smaller is due to the fact that when in 4x4, you have less traction. That slight difference allows the front end to 'pull' you forward ever so slightly more. Thats why people say never run your four wheel drive on pavement. It would create a situation that every 3.54 turns of your driveshaft (one rotation of your front wheels), your rear end would be dragged a little bit, and you might hear a chirping. Over time, that will do massive damage to the driveline. At least, thats my understanding. If Im wrong, please let me know. Im sure you gus will let me know

Rich

Feb 18, 2003 | 07:27 PM

mrwizard

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From: Vancouver WA

maybe a dumb gear ratio question

The slight difference between 3.54 and 3.55 gears isn't going to actually pull or chirp the rear tires on pavement. What it can do however, is put some serious strain on the transfer case possibly even causing a binding (or breaking) condition.

Feb 18, 2003 | 10:22 PM

steve83

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From: Memphis, TN

maybe a dumb gear ratio question

wheelMA1 & mrwizard are right - Ford used a front ratio 0.01 higher (numerically lower) than the rear in '80-96 1/2-tons, except 3.30 ratio was used F&R with the 9" rear.

Feb 20, 2003 | 11:56 AM

treehugger36

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From: The South

maybe a dumb gear ratio question

thanks guys, that cleared up alot and you learned me alot! ( <- that was an East TN joke, sorry)

thanks again for all the info

Feb 20, 2003 | 12:16 PM

Miketnf150

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Joined: Jul 1999

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From: Kingsport USA

maybe a dumb gear ratio question

So if you have to regear after putting bigger tires on your truck do you have to make sure that you get that same type setup when purchasing new gears or do you just get new gears with the same ratio?

For example:

4.09 & 4.10
or
4.10 & 4:10