Overview
The Trail Gear 140039-1-KIT is a Toyota third member assembly with a high pinion design, a 5.29 ratio and a Detroit Locker. A third member is the differential housing that carries the ring and pinion gears and the locker.
The assembly is new throughout, with no used housings or internal parts, and it installs into your existing axle housing. Match the ratio, axle and locker to your truck before ordering.
Key features
- New ring and pinion gears, bearings and differentials
- High pinion design, per the title
- 5.29 gear ratio
- Detroit Locker differential
- No used housings or internal parts
Gear setup and break-in
A third member carries the ring gear and differential, so its setup controls gear contact, backlash and bearing preload. Pinion depth and ring and pinion backlash have to be set together, and the bearings need the right preload before the cover goes on. A 5.29 ratio gives strong low-speed pull, but it also raises engine speed at highway speeds, so the rest of the drivetrain should be checked for fit.
Break-in matters for new gears. Driving gently through the first stretch of use, and avoiding hard launches and heavy towing, lets the tooth surfaces settle. Re-check the cover bolts after the first trail runs, and change the gear oil to the type the Detroit Locker needs after break-in. Some locker engagement noise on turns is typical for this type of differential.
- Check gear contact pattern before full use
- Confirm backlash and bearing preload
- Re-check cover bolts after the first runs
Specifications
| Brand | Trail Gear |
|---|---|
| Part number | 140039-1-KIT |
| UPC | 70000639722 |
| Assembly type | Third member assembly |
| Pinion | High pinion |
| Ratio | 5.29 |
| Differential | Detroit Locker |
| Condition | All new parts |
Vehicle fitment
This is a Toyota third member, and fitment for a specific model year is not confirmed. A third member is sized for a particular axle, so match the axle and 5.29 ratio to your truck before ordering.
Confirm your vehicle’s year, model and trim before ordering.
Installation notes
Gear sets like this one are usually set up by a professional, since pinion depth and ring and pinion backlash must be correct, and the gears need a break-in period. Gear work calls for the vehicle to be raised and securely supported.
What’s included
New ring and pinion gears, bearings and differential components.
Not included: The axle housing, since the assembly installs into your existing housing.
