Yukon Gear High Performance Gear Set For 14+ GM 9.5in in a 3.42 Ratio
The rear axle under a 2014-and-later Chevy Silverado 1500 or GMC Sierra 1500 is a newer 9.5 in. 12-bolt design, and it does not share gears with the 1999-2013 9.5 even though the ring gear size is the same on paper. If yours whines on the highway, has chipped teeth from a hard launch or a trailer, or you want to step up from a numerically lower factory ratio, the Yukon Gear & Axle YG GM9.5-342-12B is a new 3.42 ring and pinion built for that 2014-up axle.
The pinion gear takes power from the driveshaft and turns the ring gear bolted to the carrier, and the tooth count between them sets the final drive. At 3.42 the driveshaft turns 3.42 times for each turn of the tires. Compared with a 3.08 or 3.23, that gives more pull off the line and when towing and lets the transmission hold its higher gears with less hunting. Compared with 3.73 or deeper, it keeps cruise rpm lower, which is why 3.42 is a common choice for trucks on stock or mildly larger tires that tow occasionally. Yukon cuts the teeth from high-grade steel with a surface finish meant to reduce friction and heat, built to OEM fit.
First make sure the noise is the axle and not the transmission. An axle whine follows road speed and changes with throttle and coast, while a transmission whine follows engine rpm and changes from gear to gear; our 6L80 noise diagnosis guide covers the trans side for these trucks. Then check the factory ratio on the RPO label in the glovebox, pull the cover and inspect the teeth. If the gears look fine and only the bearings are loose, a 2014-up 9.5 master overhaul kit on its own may be the right repair.
This set is for the 2014-and-later GM 9.5 in. rear axle with a 12-bolt cover. It does not fit the 1999-2013 9.5 12-bolt, the older 14-bolt 9.5, or the 9.76 in. axle GM also used from 2014 on, mostly behind the 6.2L. Check for the size cast into the housing before you order. Yukon builds its 2014-up 9.5 gear kits around carriers designed for 3.42 and numerically higher ratios, so if your truck came with a lower ratio, confirm your carrier will accept 3.42 gears or plan to replace it. Send us your year and VIN if you want us to check. Browse more axle parts in differential hard parts, or see the 4.11 gear and install package for the same axle if you are running bigger tires.
Gears never go in on old bearings. Order the 2014-up master overhaul kit for Timken carrier and pinion bearings, shims, crush sleeve and seals, or the pinion install kit if you only need the pinion side. Remove the axle shafts to pull the carrier, set pinion depth with shims, crush the sleeve gradually to the rotating preload spec, then shim the carrier for backlash and preload and confirm the drive and coast patterns with marking compound. Use thread locker on the ring gear bolts. If the truck has the factory locker or you are adding a limited slip, now is the time to swap it. Fill with 75W-90 gear oil, avoid towing for the first few hundred miles, and change the oil early.
| Brand | Yukon Gear & Axle |
| Part number | YG GM9.5-342-12B |
| Fits | Yukon Gear High Performance Gear Set For 14+ GM 9.5in in a 3.42 Ratio |
| Type | Final Drive Gears |
| 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.
No. This set is for the 2014-and-later 9.5 in. 12-bolt axle. The 1999-2013 9.5 uses different gears even though the ring gear size is the same.
Look for the size cast into the axle housing. GM used both axles from 2014 on, with the 9.76 mainly behind the 6.2L engine. This set fits the 9.5 only.
It will help a truck that started with a lower ratio, but most owners on 33s or larger go to 3.73 or 4.11 to get back to stock-like performance. 3.42 suits stock or mildly larger tires.
No. It is the ring and pinion only. Pair it with a 2014-up 9.5 master overhaul kit for bearings, races, shims, crush sleeve and seals.
Yukon builds its 2014-up 9.5 gear kits around carriers for 3.42 and numerically higher ratios. If your truck came with a lower ratio, confirm your carrier before install.
