I have a question regarding axle ratio's... So according to the faq, they came with "Ratios: 3.21 (rare), 3.55 (normal), or 3.90 (rare). " I emailed dodge with my vin, to figure out the production codes/order... and in that list says it came with 3.92 gear ratios....

So are they actually 3.9's or 3.92's? I didnt know if it was an error in the faq or an error from dodge or what.

 

According to the parts manual it is 3.90. It is common for manufacturers to round off the numbers. If you want the truth just divide the number teeth of the pinion by the ring gear.
In any case .02 of front to back axles ratios difference is safe.

 

It is 3.92.