T3-3-4281HP – Transmission Yokes – 1350 Series – 26/27 X 1.176 Splines – 1.500″ Hub Dia

T3-3-4281HP -- Forged Chromoly 1350 Series TH700/700R4 Yoke, 26/27-Spline

The GM TH700R4 (later renamed 4L60) 4-speed overdrive automatic uses a 26/27-spline x 1.156" output shaft -- the same spline profile as the TH350, which is a common source of confusion. The key difference is the 0.410" counterbore on T3-3-4281HP, which is specific to the 700R4/4L60 output bearing retainer OD. Installing a TH350 yoke (such as T3-3-6081HP, which has no counterbore) in a 700R4 will result in off-center running and vibration at the output end.

The forged chromoly and black oxide finish make T3-3-4281HP suitable for high-performance street builds with the 700R4/4L60/4L60E transmission. The 6.938" C/U-joint to end provides adequate slip travel for most rear-wheel-drive muscle car and street rod applications. Pair with a 1350 series U-joint and inspect the 700R4 output seal before installation -- the 700R4 output seal is a known wear item in high-mileage applications.