Chevy 10-Bolt Rearend Upgrades - Get Your Rear In Gear

Before getting started, let's run down the parts that are going into this build. The Yukon Ring & Pinion (PN YG GM8.2-355) is a standard 8.2 3.55 gear ratio that is made of 8620 steel. We decided to go with middle of the road gears like the 3.55s, though these diffs were fitted with up to 4.11s from the factory. When used with an overdrive tranny, the 3.55s will be highway friendly, as well as giving significantly more torque multiplication over more pedestrian ratios like a 2.73 or 3.08.

Yukon Master Overhaul Kit (YK GM8.2) is for '64-72 GM 8.2-inch 10 bolts. Included in this kit are Timken carrier bearings and races, pinion bearings and races, a pinion seal, a complete shim kit, ring gear bolts, a pinion nut, crush sleeve (if applicable), oil baffles, and slingers (if applicable). Also included are thread locking compound, marking compound with brush, and gasket.

The axles used are (PN YA G1255802-SH). The 8.2-inch axles are 30N-inches (2.780-inch hub) and 28 spline count. On the left is the OE axle we pulled, and on the right is the new Yukon axle. Notice the Yukon axle diameter is a bit larger than that of its OE counterpart...

...and also the hub of the Yukon axle (right) compared to the OE hub is thicker as well. The Yukon axles are 20-25 percent stronger than OE due to their increased size. In some cases, it may not be necessary to buy new axles. In this case, the original axles were showing extreme wear where the bearings sit.

Forget having a peg leg wheel-the Eaton Positraction unit (PN EAT19603) uses heavy-duty internals and carbon fiber clutches for a strong, long-lasting unit. As an added bonus, the Eaton unit is also rebuildable.

Finally, the Master Power 11-inch rear drum brakes (PN DR1700K) are an alternative to a pricier set of discs for 10- and 12-bolt GM rear ends ('64-77 GM mid-size cars and '67-81 Camaro and Firebird). There is no need to change the master cylinder or proportioning valve, and all components come pre-assembled on new backing plates. You must have 3K-inch offset wheels and use 14-inch or larger wheels to clear the drum.

It would be impossible to show how the pinion gear looks installed in the housing, so we included a photo with the pinion bearing spacer (aka crush sleeve) and bearings...

...prior to installation.

A great aid that comes with this kit is the instructions. Yeah, instructions. We realize that men are not supposed to read instructions, but how else would we get the pinion preload numbers and torque specs for the ring gear bolts? The instructions included are actually user friendly and easy to understand. That's a bonus for sure. Not to mention, Randy's Ring and Pinion has a great tech line with techies who actually help you solve problems.

After the pinion gear, bearings and crush sleeve are installed, pinion bearing load is checked with an in-lbs wrench. Save the original pinion shims in order to help determine pinion depth.

The instructions call for 12-15 in-lbs of pre-load the 8.2 differential using a new pinion gear. The easiest way to check this is to rotate the pinion nut with the torque wrench. Double check the torque specs after the bearings have set. Also we used red Loctite to lock the pinion nut in place.

At first we were alarmed when the ring gear didn't seem to fit on the carrier. Our technician at Randy's told us this is normal. The ring gear is supposed to fit snugly. One way to install the ring is to lube the inside of the gear where it fits on the carrier, or by placing the ring gear in an oven with a temp no higher than 187 degrees. This will help it slip on. It's normal to have to use a rubber mallet to tap the gear into place. Just don't use a metal hammer.