My rear end has 3.08 gears and I believe that it's a series 2 carrier. I was curious what is the difference between a series 2 and series 3 rear end?

 

The rear end is the same. Theres only a difference in the gears and pinion. You can switch to a series three carreir but your going to need new gears and pinion. Setting the backlash isn't easy and is very time consuming. So finding someone good at it is a must. Costs a little more but if there Is any problems they'd have to fix it for you.

 

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Carriers