gear ratio on swapped rear end

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davesdetail
Posts: 3
Joined: Wed Jan 30, 2013 5:33 pm
Location: United States

gear ratio on swapped rear end

Postby davesdetail » Wed Jan 30, 2013 6:18 pm

I swapped out a rear end out of a '89 B2 into my '89 B2, and now it has a different ratio than the front. I have a automatic, and the one I swapped in must be from a manual I guess (I didn't check when I bought it). Now, is it easier to re-gear the front or rear?
:wtf:


Maybe the question should be; Should I keep the manual gear ratio, or go back to the gearing I had on the rear? This Bronco 2 is all stock.

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tekatlarge
Posts: 951
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: gear ratio on swapped rear end

Postby tekatlarge » Fri Feb 01, 2013 1:03 pm

It really depends on several things? The first being is what do you do the most of with your rig? Trails, Highway, Daily driver,?

Next you need to identify what gears you have now? Once you have that identified then see if one ratio is better than the other. Typically A stick has a Lower gear than an automatic. For highway and daily driving and stock tires Usually about a 3:7 to 1. They use a 4:10 for mild off road. When you use a 4:10 behind a stick Better you get pulling power but you sacrifice top speed as you wind the engine a bit tighter for the same mph. With a 4:10 you run the engine pretty hard at 60 MPH. If you use An automatic a Ratio of 3:55 to 1 or even higher like 3.0 or even 2.89 I have a 72 Galaxy with a 2.89 gear and it idles at freeway speeds almost. However with that hi a gear it is a dog getting of the line.. My B2 is just an occasional driver an I am running an automatic With 31s and running a set of 4:10s and it is snappy but shifts a bit too quick to be a nice cruzer..

There go see what you got and think about what you want. Make an informed decision from that. Have Fun and Enjoy :cool:
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

davesdetail
Posts: 3
Joined: Wed Jan 30, 2013 5:33 pm
Location: United States

Re: gear ratio on swapped rear end

Postby davesdetail » Sat Feb 02, 2013 1:19 am

tekatlarge wrote:It really depends on several things? The first being is what do you do the most of with your rig? Trails, Highway, Daily driver,?

Next you need to identify what gears you have now? Once you have that identified then see if one ratio is better than the other. Typically A stick has a Lower gear than an automatic. For highway and daily driving and stock tires Usually about a 3:7 to 1. They use a 4:10 for mild off road. When you use a 4:10 behind a stick Better you get pulling power but you sacrifice top speed as you wind the engine a bit tighter for the same mph. With a 4:10 you run the engine pretty hard at 60 MPH. If you use An automatic a Ratio of 3:55 to 1 or even higher like 3.0 or even 2.89 I have a 72 Galaxy with a 2.89 gear and it idles at freeway speeds almost. However with that hi a gear it is a dog getting of the line.. My B2 is just an occasional driver an I am running an automatic With 31s and running a set of 4:10s and it is snappy but shifts a bit too quick to be a nice cruzer..

There go see what you got and think about what you want. Make an informed decision from that. Have Fun and Enjoy :cool:

davesdetail
Posts: 3
Joined: Wed Jan 30, 2013 5:33 pm
Location: United States

Re: gear ratio on swapped rear end

Postby davesdetail » Tue Feb 05, 2013 12:05 am

Sorry Techatlarge, I was certain I had left a reply, but I do not see one. My bad. Anyway, Thank you for your reply. I'm going to stick with the gear ratio I had stock, so now I need to re-gear the rear diff to match the front.
Thanks again for your input. Cheers.


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