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373 Rear End

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Old Feb 10, 2016 | 05:53 PM
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Default 373 Rear End

I have e a 2003 Chevy Silverado and was looking for some advice on 373 Rear End gears. I was told Richmond and Yukon?
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Old Feb 10, 2016 | 06:59 PM
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What gears do you have now? What size tire? If you currently have 3.42's and are near a stock tire I would put in 4.10's. 3.73 isn't enough of a jump.
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Old Feb 10, 2016 | 07:26 PM
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Originally Posted by Vortec350ss
What gears do you have now? What size tire? If you currently have 3.42's and are near a stock tire I would put in 4.10's. 3.73 isn't enough of a jump.
Whatever is stock on a 4.8 2003 chevy
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Old Feb 10, 2016 | 07:27 PM
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Originally Posted by Vortec350ss
What gears do you have now? What size tire? If you currently have 3.42's and are near a stock tire I would put in 4.10's. 3.73 isn't enough of a jump.

I have cooper 285/55 r20 tires
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Old Feb 10, 2016 | 07:40 PM
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Well "whatever" is like 3 different options.

You might wanna check your glove box and find the RPO code for your gears. Factory options were 3.23, 3.42 and 3.73's, so you could have 1 of those 3.
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Old Feb 10, 2016 | 07:58 PM
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Most 4.8s were either 3.23 or 3.42, usually had to have a tow package or something for the 3.73s with a 4.8!!
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Old Feb 10, 2016 | 08:57 PM
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look at your G codes in the glove box.
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Old Feb 11, 2016 | 02:40 PM
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Not sure what im looking for, but here are the stickers in the glove box.


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Old Feb 11, 2016 | 03:47 PM
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Per your RPO code (google the list) you have a GT4, so you already have 3.73's it looks like. But you have no G80, so it's a open diff rear end.
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Old Feb 11, 2016 | 05:18 PM
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Originally Posted by FFDP
Per your RPO code (google the list) you have a GT4, so you already have 3.73's it looks like. But you have no G80, so it's a open diff rear end.
So a new 373 wouldn't make a difference? Do I go 411 then? Not looking to tow at all, just want horsepower. Drive across state a lot.
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