Yukon Gear Dura Grip Positraction For GM 8.5in w/ 28 Spline Axles
Older rear-drive GM cars with the 8.5 in. 10-bolt, think Chevelles, Monte Carlos, Cutlasses and G-body Regals, are the usual home of a 28-spline 8.5, and plenty of them still roll on an open carrier or a factory posi that stopped working decades ago. The Yukon Gear & Axle Dura Grip, part number YDGGM8.5-3-28-1, is a clutch-type positraction for the GM 8.5 with 28-spline axle shafts and 2.73 or numerically higher gears. It keeps the car civil on the street while putting power to both rear tires.
With an open 10-bolt, the axle shaft with the least resistance gets the torque, so a hard launch or a wet corner lights up one tire. Inside the Dura Grip, each side gear backs against a pack of composite clutch discs and steel plates. Preload springs hold the packs together lightly at all times, and under throttle the spider gears force the side gears outward and squeeze the packs harder. That friction couples the two axle shafts, so the tire that is hooked keeps driving. Through a corner the outer wheel slips the clutches and runs faster without binding. Yukon builds it with a high-strength nodular iron case, forged 4320 chromoly spider gears and composite clutches, fully rebuildable and assembled in the USA.
GM used several ten-bolt axles in the same cars, including the 7.5, 8.2 and 8.5, and they do not share carriers. Our GM 8.5 and 8.6 identification guide shows how to separate them by cover shape and ring gear size. Then count splines on an axle shaft. This unit is 28-spline only; if you count 30, use the 30-spline 8.5 and 8.6 Dura Grip. For common failure points on this axle, see GM 8.5 10-bolt problems and rebuild cost, and if you are still deciding between clutches and a locker, read open vs limited slip vs locker.
Spline count varies by year, model and options within the same car lines, and many 8.5 axles have been swapped over the years, so count before ordering rather than going by model alone. If you are not sure what is under your car, send us your year, VIN and axle code and we will help match it. More carriers and gear sets are in our hard parts collection.
| Brand | Yukon Gear & Axle |
| Part number | YDGGM8.5-3-28-1 |
| Fits | Yukon Gear Dura Grip Positraction For GM 8.5in w/ 28 Spline Axles |
| Type | Differentials |
| 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.
Pull an axle shaft and count the splines on the inner end. The model and year are not reliable on their own because GM used both counts and many axles have been swapped. This carrier is for 28 splines only.
No. It fits the GM 8.5 inch 10-bolt housing with 28-spline axles. The 8.6 takes different carrier bearings, and the 7.5 and 8.2 use different carriers altogether.
Yukon lists LM102949 cones with LM102911 races, a 2.891 inch race OD, for the 8.5 housing. A standard GM 8.5 master bearing kit includes that size.
Yes. The carrier accepts 2.73 and numerically higher ratios. The ring gear moves over to the new case with new bolts, and the backlash and pattern need to be reset.
Most chatter on a fresh clutch posi comes from synthetic oil or not enough additive. Yukon recommends non-synthetic GL-5 gear oil with its limited slip additive.
