3R03-400 – Transmission Yokes – 3R Series – 31/32 X 1.391 Splines – 1.886″ Hub Dia

3R03-400 UDS 3R Slip Yoke

The 3R03-400 is a 3R series slip yoke manufactured by UDS. The slip yoke slides over the stop shaft — the splined stub welded onto the front section of the driveshaft tube — and telescopes in and out as the suspension cycles. This allows the driveshaft to change working length without binding.

The spline bore is 31/32-inch diameter with 1.391 splines. The stop shaft on the driveshaft tube must have an identical 31/32-inch diameter and 1.391-spline profile — a mismatch in either count or diameter means the yoke will not engage. The centerline-to-end dimension is 8.000 inches, measured from the U-joint centerline to the open end of the spline bore. This controls minimum engagement depth under full suspension droop — ensure sufficient spline overlap remains at maximum driveshaft extension. GM#7838665. The 3R series uses 1.062-inch cap diameter U-joints and is standard for GM 3/4-ton and 1-ton trucks.

Specifications

• Part Number: 3R03-400
• Brand: UDS
• Series: 3R
• Center u joint to end: 8.000
• Counter bore dia: 0
• Hub dia: 1.886
• Notes: GM#7838665
• Splines count dia: 31/32 X 1.391

Fitment & Installation Notes

When selecting the 3R03-400, verify the stop shaft spline count and diameter match the 31/32 X 1.391 specification. Inspect the stop shaft for wear or damage; a worn shaft will produce lash even with a new yoke.

View the full range of Transmission Yokes in 3R and adjacent series configurations.