Here you go.....
A-727 transmissions from their inception until 1966 have 19 splines on the input shaft. Non-lockup 727 transmissions from 1967 onward have 24 splines. Lockup 727 transmissions that debuted in 1978 had 23 splines.
Not all 727 transmissions made after 1978 were lockup; specifically towing package 727 transmissions commonly were non-lockup, and would have the '67-onward 24 spline input shaft. The A-518 overdrive also has 23 splines. The output shaft has 29 splines.
A-904 transmissions from their inception until 1967 have 18 splines in the input shaft. Non-lockup transmissions from 1968 have 27 splines.
Lockup 904 transmissions appeared in 1978, and have 26 splines. A-500 overdrive transmissions also have 26 splines. The output shaft has 25 splines.
If in doubt, count the splines. It saves a lot of headache and stress later on when you might otherwise discover that you have the wrong torque converter or drive shaft yoke.
A-727 transmissions from their inception until 1966 have 19 splines on the input shaft. Non-lockup 727 transmissions from 1967 onward have 24 splines. Lockup 727 transmissions that debuted in 1978 had 23 splines.
Not all 727 transmissions made after 1978 were lockup; specifically towing package 727 transmissions commonly were non-lockup, and would have the '67-onward 24 spline input shaft. The A-518 overdrive also has 23 splines. The output shaft has 29 splines.
A-904 transmissions from their inception until 1967 have 18 splines in the input shaft. Non-lockup transmissions from 1968 have 27 splines.
Lockup 904 transmissions appeared in 1978, and have 26 splines. A-500 overdrive transmissions also have 26 splines. The output shaft has 25 splines.
If in doubt, count the splines. It saves a lot of headache and stress later on when you might otherwise discover that you have the wrong torque converter or drive shaft yoke.
