Yukon Gear Pinion install Kit For 08 & Down GM 8.6in Diff
A howl from the back of a 1999-2008 Silverado 1500, Sierra 1500, Tahoe, Yukon, Suburban 1500, Trailblazer, Envoy or Colorado that rises and falls with speed usually traces to the pinion bearings in the GM 8.6 inch ten-bolt, especially after a regear or a long stretch of towing. The Yukon Gear and Axle PK GM8.6-A is the pinion-side install kit for 2008-and-earlier 8.6 rears: Timken pinion bearings and races, a pinion seal, crush sleeve, a complete pinion shim kit and marking compound with a brush.
In the 8.6 the pinion gear rides on two tapered roller bearings, a large inner bearing behind the gear head and a smaller outer bearing near the yoke. A shim under the inner bearing race sets pinion depth, which decides where the teeth contact the ring gear. A collapsible crush sleeve between the bearings holds preload once the pinion nut is torqued. When those bearings wear, the pinion can move under load, the contact pattern shifts and the gears start to whine or growl. Yukon builds this kit for gear installs on lower-mileage axles where the carrier bearings and races are still good enough to reuse, so you buy only the pinion-side parts instead of a full master kit.
Separate the pinion from the carrier first. Pinion bearing noise is loudest on acceleration and deceleration and follows driveshaft speed, while carrier bearing noise tends to be a steady rumble that changes in turns. Our pinion bearing noise guide walks through the test drive, and whine on acceleration vs deceleration explains what each load points to. If the carrier bearings are also rough, skip this kit and buy a complete setup kit such as the GM 8.6 ring and pinion installation kit so both sides are new.
Yukon lists this kit for the 1999-2008 GM 8.6 rear, including the Silverado 1500 and Sierra 1500 (2WD and 4WD), Tahoe and Yukon, 2000-2008 Suburban 1500 and Yukon XL 1500, 2002-2008 Trailblazer and Envoy, 2004-2008 Colorado and Canyon, 2002-2006 Avalanche 1500 and 2007-2008 Avalanche, 1999-2008 Savana 1500 and 2003-2008 Express 1500, 2000-2008 Escalade, 2003-2006 SSR, 2006-2008 Hummer H3, 2003-2008 Isuzu Ascender, 2004-2007 Buick Rainier, 2005-2008 Saab 9-7x, and 1999 C/K 1500, 1999-2000 C2500 and 1999-2004 S10 and Sonoma applications that came with the 8.6. GM used the 7.5/7.625, 8.5, 8.6 and 9.5 in the same model lines, so count the cover bolts and read the axle code on the RPO sticker before ordering. The 2009-and-later 8.6 and the Camaro 8.6 IRS take different kits. Send us your year and VIN if there is any doubt. Our GM 8.5 and 8.6 ring and pinion kit guide covers the ID points.
Mark the yoke and pinion, measure the existing rotating torque, then remove the pinion and pull the old inner bearing off the gear head with a clamshell tool such as our carrier and pinion bearing puller or a press. Drive in both new races fully seated. Yukon's setup chart lists the GM 8.5 and 8.6 with a .037 in. OEM pinion shim, 14-19 in-lb pinion preload with new bearings (6-8 used), 65 ft-lb on the ring gear bolts and 60 ft-lb on the carrier caps. Tighten the pinion nut in small steps and check preload each time; if you overshoot, the crush sleeve has to be replaced, never backed off. Paint the ring gear with the supplied marking compound and read the pattern before final assembly. The kit list does not include a pinion nut or ring gear bolts, so plan for those. Most buyers pair it with a new gear set like the 3.73 GM 8.5/8.6 ring and pinion. Refill with 75W-90 gear oil, add friction modifier if the axle has a limited slip, and seal the cover with a fresh gasket or our chrome ten-bolt cover.
| Brand | Yukon Gear & Axle |
| Part number | PK GM8.6-A |
| Fits | Yukon Gear Pinion install Kit For 08 & Down GM 8.6in Diff |
| Type | Ring and Pinion Install Kits |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Timken pinion bearings and races, a pinion seal, a crush sleeve, a complete pinion shim kit, and marking compound with a brush. Carrier bearings, a pinion nut and ring gear bolts are not part of this kit.
No. This is the 2008-and-earlier 8.6 kit. Yukon splits the 8.6 at 2008, and the 2009-up axle and the Camaro 8.6 IRS take different kits. Send us your VIN and we will match the right one.
When the carrier bearings and races are still smooth and tight, as on a lower-mileage truck getting new gears. If the carrier bearings are rough, pitted or noisy, buy a full kit so both sides are replaced together.
Only if you mark the nut position and measure the rotating torque first, then return to the same reading. Over-tightening crushes the sleeve further and overloads the bearings, which leads to whine and early failure.
Yukon's setup chart lists 14-19 in-lb with new bearings and 6-8 in-lb with used bearings for the GM 8.5 and 8.6, measured with the pinion turning and no carrier installed.
75W-90 gear oil filled to the bottom of the fill hole, plus friction modifier if the truck has a limited slip or the factory G80 locker requires it per its service information.
