3R03-703 Transmission Yoke Inside Snap Ring 3R TH 700/700R4 ,It has the same spline and ground hub as a Turbo 350 yoke but is approximately 1.3″ longer.

Dimensional Context: The 3R03-703 runs approximately 1.3" longer than the TH350 yoke (3R03-350 at 5.460" vs. 6.750" C-to-end). This extra length is required by the TH700R4/4L60E overdrive case, which extends the tailshaft distance from transmission mount to output shaft end by approximately 1.3" compared to the TH350. Installing the shorter TH350 yoke will leave the slip tube under-engaged and cause vibration and potential separation.

The 3R03-703 is the inside snap-ring version of the TH700R4 transmission yoke for the 3R series (GM part 26051658 cross-reference). The "inside snap ring" retention groove is in the yoke bore, which mates with a groove in the output shaft OD -- this design was used on later production GM transmissions as a cost reduction over the external-groove retention. If your TH700R4 was rebuilt and the tailshaft was replaced, verify which snap-ring style the replacement shaft uses before ordering. The standard 26/27 x 1.176" spline and 1.500" hub specifications are identical to all GM 26/27-spline yokes; only the retention style differs.