Yukon Gear High Performance Thick Gear Set For 10.5in GM 14 Bolt Truck in a 5.13 Ratio
A 5.13 is the ratio people pick when a 3/4-ton or 1-ton Chevy or GMC with a full-floating 14-bolt rear is going onto 37 to 40 in. tires, or when an old work truck is being turned into a rock crawler or a dedicated heavy hauler. Yukon part YG GM14T-513T is a 5.13 ring and pinion for the GM 10.5 in. 14-bolt truck axle, and it is the "thick" version, built so it bolts to the carrier you already have.
The 10.5 in. 14-bolt is a full-floating axle: the hubs ride on bearings on the axle tubes, so the shafts only transmit torque and the ring and pinion take the load. This set has a 10.50 in. ring gear, 12 ring gear bolts and a 30-spline pinion that rides in three bearings, including the pinion support bearing at the nose. Going from a factory 4.10 to 5.13 raises torque at the tire about 25 percent, enough to bring back the launch and grade-holding power that 37s or 40s take away.
The thick part is the key. GM 14-bolt carriers come in two series by ratio. Normally a ratio this deep would need the carrier for 4.56 and up, but this thick ring gear is made to mount on the 4.11-and-down carrier found in trucks that came with 3.73 or 4.10 gears. That lets you keep your existing carrier, limited slip or locker instead of buying a new one.
Count the cover bolts (14) and confirm the axle is the 10.5 in. full-floater, not the 9.5 in. semi-float 14-bolt and not the AAM 11.5 used in later heavy-duty trucks; the 14-bolt vs AAM 11.5 comparison shows how to tell them apart. Read the ratio tag or count teeth so you know which carrier you have, using this axle ratio guide. For noise complaints, the GM 14-bolt problems and rebuild cost guide separates gear noise from bearing wear.
Fits the GM 10.5 in. 14-bolt full-floating truck rear axle with a 30-spline pinion, as used under Chevrolet and GMC 3/4-ton and 1-ton pickups, Suburbans and vans. GM changed to the AAM 11.5 in many heavy-duty pickups in the 2000s, so check the axle itself rather than going by model year. Because this is a thick gear for the 4.11-and-down carrier, it will not seat correctly on a 4.56-and-up carrier; that carrier needs a standard 5.13 set. Not sure which you have? Send us your year, VIN and the axle tag. Want even more reduction? See the 5.38 thick set, or the 4.11 set for a milder build.
Yukon's setup chart lists, for the 14-bolt with pinion support, an OEM pinion shim of about 0.017 in., 20-35 in-lb of pinion bearing preload with new bearings (8-11 with used), 0.006-0.011 in. backlash, 120 ft-lb on the ring gear bolts and 135 ft-lb on the carrier caps. Set depth, preload and backlash, then read the pattern with marking compound. Replace all bearings, races, the seal and crush sleeve at the same time with a 14-bolt master install kit, or a crush sleeve eliminator if the truck sees hard use. If you want traction that stays on your carrier series, the Dura Grip for 4.10-and-down matches this thick gear. Fill with 75W-90 or 75W-140 gear oil, drive 15-20 miles and let it cool, avoid towing for the first 500 miles, then change the oil.
| Brand | Yukon Gear & Axle |
| Part number | YG GM14T-513T |
| Fits | Yukon Gear High Performance Thick Gear Set For 10.5in GM 14 Bolt Truck in a 5.13 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.
Not with this set. It is the thick version made for the 4.11-and-down carrier, so a truck that came with 3.73 or 4.10 gears keeps its carrier.
No. Thick gears will not set up on the deep-ratio carrier. That carrier takes a standard, non-thick 5.13 set.
No. It fits only the 10.5 in. full-floating 14-bolt truck axle with a 30-spline pinion.
It is usually chosen for 37 to 40 in. tires on heavy trucks, or for stock-size trucks that tow very heavy loads at low speed. Your front axle must be regeared to the same ratio on a 4x4.
A 14-bolt master install or overhaul kit with pinion and carrier bearings, the pinion support bearing, seal and crush sleeve or a crush sleeve eliminator, plus 75W-90 or 75W-140 gear oil.
