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Old 05-13-2015, 05:49 PM   #1
Jaymans82
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Rear End Gears

Hello
I have a 82 chevy c10 LWB with a 383 stroker with a 700R4 with lockup.
I think my gears are 308's which I think are to high. What gear should I go with 342 or 373?
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Old 05-13-2015, 07:50 PM   #2
Jake Wade
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Re: Rear End Gears

I personally like a 3.73 with a 28"-30" tire and a 700R4.

3.42 for 25"-27"
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Old 05-14-2015, 07:19 AM   #3
Keith Seymore
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Re: Rear End Gears

3.73.

They are perfect with the overdrive trans.

K
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Old 05-14-2015, 08:17 AM   #4
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Re: Rear End Gears

What Keith said....
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Old 05-14-2015, 10:41 AM   #5
piecesparts
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Re: Rear End Gears

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Originally Posted by 77c10 View Post
What Keith said....
Yep, we are all in agreement, the 3.73 works the best with a 700 R4 tranny.

My truck is a 383 stroker, 700R4 tranny, 28" tall tire, with a 12 bolt 3.73 geared rear end.
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Old 05-14-2015, 11:28 AM   #6
Jaymans82
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Re: Rear End Gears

OK I'm guessing when you say 12 bolt that that is the bolts on the cover. If so I only have 10 bolt. should I find a 12 bolt are is a 10 good enough?
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Old 05-14-2015, 09:32 PM   #7
RIDE-RED 350r
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Re: Rear End Gears

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Originally Posted by Jaymans82 View Post
OK I'm guessing when you say 12 bolt that that is the bolts on the cover. If so I only have 10 bolt. should I find a 12 bolt are is a 10 good enough?
I don't know about your area, but here in my area I had a heck of a time sourcing a 12-bolt truck axle when mine grenaded last summer.

I don't know whether or not a 12-bolt is that much heavier duty than the 10 to justify the search for one. The ring gear in the 12-bolt is little larger than the 10-bolt (8.875" to 8.5" respectively) Also, the 12-bolt uses 12 bolts to fasten the ring gear to the carrier where the 10-bolt uses 10.

I am not certain if there are more things the 12-bolt axle has over the 10 beyond that, or if these make the 12-bolt significantly tougher either. I would defer to some of the more experienced members here on that subject.

Also, it should be noted that the 12-bolt passenger car axle is different than the truck axle. The car axle seems to be more desirable to builders from what I gather. Seems like I have read that the truck axle has a smaller pinion shaft.

But if it were me and I intended to flog an axle with bigger HP and torque and decided to swap axles for something better suited to that than the 10-bolt, I would get something heavier than the 12-bolt..along the lines of a Dana 60 or GM 14-bolt FF.
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