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  #1  
Old 04-18-2016, 06:25 PM
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changing gear ratio

How do I find out what differential I have? I have an 08 Laredo AWD. I want to switch to 3.73 in the front and rear. What would I need to complete this?

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Old 04-18-2016, 07:45 PM
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Re: changing gear ratio

If you go to the jeep dealer with your vin they can give you a print out of all options you have including your gear ratio.
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Old 04-22-2016, 05:02 PM
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Re: changing gear ratio

Chrysler 8.25 in the rear

With the 3.7L it's 3.07:1
With the 4.7L it's 3.73:1

Front and rear ratios are the same.




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Old 04-29-2016, 02:25 PM
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Is it the same for the front? I have all wheel drive... I have to change the gears up front too? Correct?
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Old 04-29-2016, 03:07 PM
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Re: changing gear ratio

Quote:
Originally Posted by barak View Post
If you go to the jeep dealer with your vin they can give you a print out of all options you have including your gear ratio.
You don't need to go to the dealership to get this information, you can use this Jeep's webservice :
http://www.jeep.com/webselfservice/B...etServlet?vin=

You have to type your VIN after " = " symbol.

Example
http://www.jeep.com/webselfservice/B...GW68J94C399095
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Old 04-30-2016, 01:37 PM
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Quote:
Originally Posted by whhjr73 View Post
Is it the same for the front? I have all wheel drive... I have to change the gears up front too? Correct?
Yes
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Old 04-30-2016, 01:41 PM
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Quote:
Originally Posted by whhjr73 View Post
How do I find out what differential I have? I have an 08 Laredo AWD. I want to switch to 3.73 in the front and rear. What would I need to complete this?
Rear is Chrysler 8.25 (C213R)
Front is a C200 in the same ratio as the rear. Both are an open differential.

I myself am currently in the process of rehearing the rear end as I am only Rwd. But I'm going a bit further then just a gear swap. I'm also replacing the open dif for a limited slip from Detroit locker and getting 3.73 gears from Yukon gear
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Old 05-01-2016, 11:47 AM
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Old 03-31-2017, 02:56 PM
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Re: changing gear ratio

so...there's no difference between the front and rear. size..etc..
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Old 03-31-2017, 05:18 PM
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Quote:
Originally Posted by whhjr73 View Post
How do I find out what differential I have? I have an 08 Laredo AWD. I want to switch to 3.73 in the front and rear. What would I need to complete this?

Jack the rear up. Make a mark on the drive shaft and differential in the same place. Then make a mark on the tire. turn the tire one full turn while watching how many turns the drive shaft makes. If the drive shaft makes 3 turns it's a 3.07:1, 3 3/4 turns is a 3.73:1. The gear ratio can be thought of as how many turns of the diff per one turn of the wheel.
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Old 04-01-2017, 12:27 AM
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Re: changing gear ratio

Quote:
Originally Posted by whhjr73 View Post
How do I find out what differential I have? I have an 08 Laredo AWD. I want to switch to 3.73 in the front and rear. What would I need to complete this?
The short answer is a bunch of money. Doing so may also throw off the computers and such and might cause other problems. Are you doing this to make your 3.7 faster?
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Old 04-01-2017, 07:29 AM
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It wouldn't have an effect on the computer except the speedo. Assuming there's no elsd involved. Putting on oversized tires would actually lower your gear ratio. A bigger diff can compensate.
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