Revolution Gear & Axle Ring & Pinion Set for GM 8.5" & 8.6" 10-Bolt (3.42 Ratio, Face Hobbed)

This is the Revolution Gear & Axle ring and pinion set for the GM 8.5" and 8.6" 10-bolt axle in a 3.42 ratio with standard rotation. It is a direct gear replacement for one of the most common GM truck and SUV rear axles.

The set is a face-hobbed (2-cut) gear, dry cut and then lapped for smooth, quiet operation, and is machined from 8620 alloy steel and heat treated to meet or exceed OE standards. It uses a 30-spline pinion and an 8.5-inch ring gear, with the carrier break at 2.56/2.73.

A 3.42 is a practical ratio for GM trucks and SUVs that want a stronger, fresher gear set without a deep numerical change – keeping highway RPM sensible while improving on a tired or numerically lower factory ratio.

This is a gear set only. It does not include bearings, a crush sleeve, shims, or a pinion seal, and it does not include a carrier or traction device. Confirm your carrier suits the 3.42 ratio relative to the 2.56/2.73 break, and plan on a master install kit.

Pair it with a Revolution Gear master install kit for the GM 8.5/8.6 10-bolt to get the bearings and setup hardware for a clean install. Gears carry a 2-year warranty against manufacturing defects.