Multi-stage Stud-Piloted Disc Wheels
Found on trailers in our fleet — dual inner/outer cap nuts with spherical seats.
- Tighten all inner cap nuts / lug nuts to 50–100 ft-lbs first.
- Ensure the wheel is properly mounted and centered.
- Torque fully to 450 ft-lbs following the pattern below.
Stud sizes: 3/4″-16 inner · 1 1/8″-16 outer. Spec: 450–500 lb-ft (610–680 N·m). Cap-nut seats are spherical (7/8 radius ball) — seat them square.
Torque Spec Table
Tightening Pattern
Inner Cap Nut · Duals
Spherical Seat
Single-stage Hub-Piloted Wheels
Found on most trucks and some trailers — flange nuts, hub pilots/guides align the wheel. (PACCAR ISO Hub-Pilot · Budd Uni-Mount-10 · PHP-10)
- Ensure the wheel is properly mounted and centered — use the hub pilots / guides to align.
- Torque fully to 450 ft-lbs following the pattern (same star pattern as above).
| Wheel & Nut Configuration | Stud Size | Torque (lb-ft) | Torque (N·m) |
|---|---|---|---|
| Standard Disc Wheels | 3/4″-16 inner · 1 1/8″-16 outer | 450–500 | 610–680 |
| PHP-10 · Budd Uni-Mount-10 · WHD-8 | M22 × 1.5-6H | 450–500 | 610–680 |
Pattern · Pilot Pads
Flange Nut · Stud
Hub-Pilot Stud
Torque Spec Table
Power Steering
PACCAR MX engine (EPA 17) power-steering pump reference.
Power-steering pump as mounted on the PACCAR MX. For pump specs, fittings, and service detail, open the full OEM reference.
