Gear codes

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bowtiefreak

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It has come up more and more. Everyone should know whats in the truck. Below are the stock gear codes found in the glove box. You will have one and possibly two of the following codes if you have the G80 option. I have also listed a helpful gear to tire size chart to help people better understand.

GT4 -- AXLE REAR, 3.73 RATIO
GT5 -- AXLE REAR, 4.10 RATIO
GU4 -- AXLE REAR, 3.08 RATIO
GU5 -- AXLE REAR, 3.23 RATIO
GU6 -- AXLE REAR, 3.42 RATIO
G80 -- AXLE REAR, locking differential (has many names, none being good but that brings up a whole other discussion)

gear_ratio_chart1.gif
 

BluHoe96

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Wow! Big help on this glad u posted it. Looking for a rim and tire setup now so this is a big help!
 
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Bowtiefreak. I was wondering if I run a 3" body lift along with a 3" suspension and run 35 or 36 tires am I gonna run into trouble not regearing my truck?
 

raptorforme93

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I was perfectly fine not knowing that I have the G80!!! But I do :( Im about %90 sure that it doesnt work, but I havent tested it out. And I have a 3.42 ratio which also isnt fun. Thanks for the info though! I would never have known otherwise
 

Bad bow tie

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Bowtiefreak. I was wondering if I run a 3" body lift along with a 3" suspension and run 35 or 36 tires am I gonna run into trouble not regearing my truck?

35" you should have at least 4.56 gears. Anything bigger should be 4.88 or even 5.13. You could probably get by on 4.10s for 35's but you will run the risk of putting extra strain on your engine and tranny.
 

ELOOSECANNON

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How can you tell which code you have? I looked at the sticker in the glove box and there's like 6 or 8 columns of codes. Which ones are for what? I'm confused.
 

Bad bow tie

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The codes are given in a number/letter ratio. For example: GT4 stands for a trucks gear ratio.. this specific code means the truck has 3.73 gears. Yours may be different. These codes give every option your truck came with from the factory. I.E. trim level, packages, everything from leather interior to sterio system to mechanics like tranny type, gear ratios, and engine types. It tells you everything and is pretty much a build sheet for your vehicle.

The best thing to do is to take a picture of your label located in the glove box and look them here http://www.rpocodes.com/

Hope this helps.
 
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