Axle rear end question

[Carnage5oh_s197]

Hi, I have a 2012 gt and I’m trying to figure out what rear end it has. The sticker on the door jam says GG but the the one on the axle says BB. Anybody had this issue before? or am I looking at the wrong sticker in the axle?

 

[Gladams]

GG code is 3.31 gear code. Looks like the Rearend tag is missing with the different plate. Isn’t the BB the axle code length? Not sure,but my 12 gt has the GG code and the diff has 3.31 on the tag hanging from the bolt. Thanks.

 

[JC SSP]

I remember Reading about the finned rear cover means track pack which comes with 3:73 and Torsen differential but I see a lot of BMR upgrades so this could be a cover change only.

There are several ways of confirming what gears you have.

HOW TO: Determine the Rear Axle Ratio you have - Modern Driveline

Knowing your rear end’s gear ratio is crucial when you are considering a transmission upgrade

www.moderndriveline.com

 

[Miker]

I remember Reading about the finned rear cover means track pack which comes with 3:73 and Torsen differential but I see a lot of BMR upgrades so this could be a cover change only.

There are several ways of confirming what gears you have.

HOW TO: Determine the Rear Axle Ratio you have - Modern Driveline

Knowing your rear end’s gear ratio is crucial when you are considering a transmission upgrade

www.moderndriveline.com

I believe track pack axels are painted .

 

[Red-Candy-Metallic]

The BB code on the axle tube may be coincidental?
Most MT-82 (manual) cars were probably built with the 3.31 axle ratio.
Most 6R80 (automatic) cars were probably built with the 3.15 axle ratio.

This is the list of codes: (found here: https://support.bamaperformance.com/hc/en-us/articles/207043046-11-14-Axle-codes-found-on-door-plate)
BB – 3.73
DD – 3.55
GG – 3.31
YY – 3.15
CC – 2.73

I ordered my 2012 GT with the optional 3.73 and it is indicated on the door tag. I never looked for the tag on the actual differential cover.

 

[Carnage5oh_s197]

Thanks guys! I appreciate the help. I’m just gonna have to get the car on stands and spin the tires. And count how many times the driveshaft spins, before the wheel gets back to its mark. I believe thats the only real way of knowing. I Just thought it was odd that the sticker on the axle said that BB and the one inside the door GG. I was already thinking of swapping them out for some 3:73s. And hopefully I won’t have to.

 

[nyuk98GT]

Carnage5oh_s197,

Best method is a physical test:
* Lift the rear wheels off the ground.
* Put a mark on the driveshaft and put a mark on teh inside of one rear tire. Masking tape works nicely.
* Rotate the driveshaft, counting each revolution, until the tire has made one revolution.
* Calculation: driveshaft revolutions/1 = gear ratio

Alternate method is a 2-person job and may have to be repeated because the driveshaft flag position is hard to see (in my opinion):
* Wrap some masking tape on the driveshaft leaving a starting tail of 4" to 6" and bring the tape around to leave a 4" to 6" tail then stick the two pieces together to make a flag.
* Mark the outside of a rear tire (say, at 6 or 12 o'clock).
* Have the 2nd person slowly roll the car and count the revolutions that the flag makes until the tire has made one revolution.
* Calculation is the same.

HTH,

Chris

 

[Red-Candy-Metallic]

Thanks guys! I appreciate the help. I’m just gonna have to get the car on stands and spin the tires. And count how many times the driveshaft spins, before the wheel gets back to its mark. I believe thats the only real way of knowing. I Just thought it was odd that the sticker on the axle said that BB and the one inside the door GG. I was already thinking of swapping them out for some 3:73s. And hopefully I won’t have to.

Did you figure out what you have for a rear axle ratio?

 

[86GT351]

This is what your Oasis says per vin

 

[86GT351]

This is what the build sheet says