Overview
The G2 GM 8.5 inch 10 bolt front axle spindle, part number 99-2021-1, is a replacement front spindle for GM 8.5 inch 10 bolt axles. It is a high strength replacement for worn originals in popular applications.
It covers 1977-1991 GM K5 and Suburban 1/2 and 3/4 ton trucks, along with 1977-1987 GM 1/2 and 3/4 ton trucks. It is precision machined from forged steel with a 6 bolt mounting pattern.
Key features
- Precision machined from forged steel
- 6 bolt mounting pattern
- Front axle location
- Replacement spindle for 8.5 inch GM 10 bolt front axles
Choosing a replacement spindle
GM 10 bolt 8.5 inch front axles use a spindle that carries the hub and bearing assembly, so the spindle must match the axle and steering setup. Check the hub’s bolt pattern and the spindle’s bearing surfaces before buying, since a near match can still look similar and fit poorly. Measuring the existing spindle or comparing it side by side with the new part is a practical step.
Replacing a worn spindle often means replacing the hub, bearings and seals too. Inspect the steering arms, ball joints and brake backing plate for damage before installing, as those parts see the same loads. Keep the hardware and torque steps from the service procedure close at hand. A spindle that binds or runs hot after assembly needs to be checked before the vehicle is driven.
Specifications
| Brand | G2 Axle and Gear |
|---|---|
| Part number | 99-2021-1 |
| UPC | 631410111873 |
| Axle location | Front |
| Axle type | GM 10 bolt 8.5 inch |
| Material | Forged steel |
| Mounting pattern | 6 bolt |
Vehicle fitment
Applications run from 1977-1991 for GM K5 and Suburban trucks and from 1977-1987 for GM 1/2 and 3/4 ton trucks. No individual vehicles are linked to this spindle.
Confirm your vehicle’s year, model and trim before ordering, since years outside 1977-1991 fall outside the applications above.
What’s included
Only the spindle is included. Hub, bearings and hardware are separate parts, so check them against your setup before installing.
