Yukon Gear 65-69 GM 12 Bolt Truck 5 Lug Conversion Kit

Building a 1965-1969 Chevrolet C10 or GMC half-ton and tired of hunting for six-lug wheels? Yukon Gear and Axle kit YA G6569RACK converts the GM 12-bolt truck rear axle to a 5-lug pattern in one box. Yukon lists the kit as including two 30.75-inch, 30-spline axle shafts, brake drums, axle bearings, wheel seals and wheel studs, so the rear end comes out of the job with new shafts and new wear parts instead of 55-year-old ones.

What this kit changes on a GM 12-bolt truck rear

The truck 12-bolt is its own axle, not a car 12-bolt under a pickup. It has an irregular-shaped cover, a narrower carrier, a smaller inner pinion bearing, and different axle bearings, and car axles will not work in a truck housing. Many of these trucks also left the factory with six-lug hubs. Because the shafts are C-clip retained, the wheel bolt pattern is set by the flange on the axle shaft itself, so new shafts with a 5-lug flange, matching drums and new studs are what it takes to change the rear pattern. The new shafts are 30 spline, which is the common aftermarket spline count for this axle and stronger than the large-spline shafts found in early truck 12-bolts.

Reasons owners do this conversion

• Wheel choice: far more modern and restomod wheels are made in 5-lug patterns than in the old truck six-lug.
• Worn original shafts with grooved bearing journals that leak gear oil past new seals.
• Rear wheel bearing growl or a drum that pulses under braking.
• An axle rebuild already planned, where buying shafts, bearings, seals and drums separately would cost more time chasing parts.

How to confirm your rear end before you buy

First make sure it is a truck 12-bolt: count twelve cover bolts and look for the irregular truck cover shape rather than the rounder car cover. Our GM 10-bolt vs 12-bolt guide walks through identification, including why the 8.875-inch truck axle is different from the 9.5-inch 12-bolt used on 1999-and-later trucks. Next, pull a shaft and count its splines. These shafts are 30 spline, so the side gears in your carrier must also be 30 spline. If your truck still has original large-spline axles, plan on 30-spline side gears such as the USA Standard 30-spline 12-bolt spider gear kit, or a 30-spline carrier.

Fitment

Yukon lists this kit for the GM 12-bolt truck rear in 1965-1969 Chevrolet C10 pickups, 1967-1969 Chevrolet K10 Suburban, 1965-1966 Chevrolet Suburban, and 1966-1969 GMC K15/K1500 pickups. Shaft length is 30.75 inches, so a narrowed or swapped housing will not match. The kit covers the rear axle only; plan the front brakes and hubs separately so both ends end up on the same bolt pattern. It is a large, heavy package with a listed shipping weight near 82 lb. If your truck has been modified or you are not sure what is under it, send us the year, VIN and axle code before ordering. More rear-end parts are in our rebuild kits category.

Install notes

• Drain the gear oil and remove the cover. Remove the pinion shaft lock bolt and pinion shaft, push each axle inward, and take out the C-clips before sliding the old shafts out.
• Drive out the old seals and bearings and install the new ones from the kit with a proper driver, then install the new shafts and C-clips and reinstall the pinion shaft and lock bolt.
• Inspect brake shoes, wheel cylinders and hardware before fitting the new drums, and adjust the shoes so the drums just drag.
• If the ring and pinion is due, do it now with the Allstar GM 12-bolt truck install kit, and replace the leaky stamped cover with a Yukon chrome 12-bolt truck cover.
• Refill with 75W-90 gear oil, adding friction modifier if the carrier is a clutch-type posi, and retorque the lug nuts after the first drive.

What comes in the YA G6569RACK kit?

Yukon lists 30.75-inch, 30-spline axle shafts, brake drums, axle bearings, wheel seals and wheel studs for the GM 12-bolt truck rear.

Will it fit my car 12-bolt from a Chevelle or Camaro?

No. The car and truck 12-bolts use different axles, bearings, carriers and bolt patterns. This kit is for the truck 12-bolt only.

Do I need a new carrier or spider gears?

Only if your side gears are not 30 spline. Count the splines on an old shaft; early truck 12-bolts used large-spline axles, which need 30-spline side gears or a 30-spline carrier to use these shafts.

Does this convert the front of the truck too?

No. It covers the rear axle only. Plan the front hubs and brakes separately so all four wheels share the same pattern.

Which years and models are listed?

Yukon lists 1965-1969 Chevrolet C10, 1967-1969 Chevrolet K10 Suburban, 1965-1966 Chevrolet Suburban and 1966-1969 GMC K15/K1500 pickups with the 12-bolt truck rear.