Overview
The G2 2-2015-308 is a 3.08 ratio ring and pinion for GM 10 Bolt rear axles. The drive pinion turns 3.08 times for each revolution of the ring gear, a numerically lower ratio that keeps engine rpm down at highway speed. It fits both 7.5 inch and 7.625 inch ring gear sizes, so measure the ring gear on your housing first.
A 3.08 ratio means the drive pinion turns 3.08 times per revolution of the ring gear. It is a numerically lower gear that keeps engine rpm down at highway speed. G2 says its Performance line is made for oversized tires and high-performance engines, with current materials and manufacturing.
Key features
- 3.08 gear ratio for GM 10 Bolt rear axles
- Fits 7.5 inch and 7.625 inch ring gears
- Ring gear and pinion supplied as one matched set
- Designed, per G2, for oversized tires and high-performance engines
- Rear axle location
Measuring your ring gear
On a GM 10 Bolt, the ring gear diameter decides which gear set will mount in the carrier. The two common sizes are 7.5 inch and 7.625 inch, and they are not interchangeable. Measure across the ring gear teeth from one side to the other, or read the size stamped on the housing or carrier, before buying a set.
Ratio choice matters as much as size. A numerically lower ratio like 3.08 keeps engine speed down on the highway and suits steady cruising, while a higher number helps low-speed pulling. Tire diameter changes the effect, so consider tire size together with the gear ratio. Inspect the pinion bearings and carrier bearings during the change, and replace parts that show wear.
- Measure the ring gear before ordering
- Check the carrier stamp for the ring size
- Replace pinion bearings if they show play
- Verify backlash and tooth contact before driving
Specifications
| Brand | G2 Axle and Gear |
|---|---|
| Part number | 2-2015-308 |
| UPC | 631410105575 |
| Axle type | GM 10 Bolt, 7.5 inch or 7.625 inch ring gear |
| Axle location | Rear |
| Gear ratio | 3.08 |
| Axle manufacturer | GM |
Vehicle fitment
It is matched to GM 10 Bolt rear axles with either ring gear size. Measure the ring gear and confirm the carrier on your vehicle before ordering, since a different GM axle will not be the right part.
Confirm your vehicle’s year, model and trim before ordering.
Installation notes
Pinion depth, backlash and carrier preload all affect a 10 Bolt gear set, so a gear shop with setup tools is the usual installer. Expect a break-in period before sustained heavy use.
What’s included
One ring and pinion set for GM 10 Bolt rear axles, part number 2-2015-308.
Not included: Carrier bearings, shims and installation hardware are sold separately and may need to be bought.
