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

The 3R03-400 is the maximum-length 3R-series variant for TH400 applications at 8.000" center-to-end. This length is required for Long TH400 tailshaft configurations or for custom builds where maximum driveshaft slip engagement is required for safety -- for example, tube-frame race cars where chassis flex under acceleration could otherwise compress the driveshaft to the point of withdrawal from the yoke.

• 3R inside snap-ring retention -- must match output shaft grove style
• 31/32 x 1.391" PD -- 3R series; 0.006" smaller than T2-3 series; not interchangeable
• 1.886" hub OD -- requires 1.886" tailshaft seal bore; verify seal size before installation
• 8.000" C-to-end -- longest 3R TH400 variant; calculate driveshaft tube length to account for full engagement at both extremes of suspension travel
• GM part reference: 7838665; use for factory service manual verification

Tip: after installing this long yoke, verify driveshaft tube engagement at full suspension compression and full droop. Minimum recommended engagement for a 1310-series slip is 2.000" of tube engagement on the yoke spline at all suspension positions. Measure at full compression -- this transmission yoke is long enough that bottoming can occur in short-wheelbase applications with aggressive suspension travel.