727 or 904

[GN]

How can one tell the differance from a 727 and a 904?

[OttawaCharger]

They look almost identical.  You'll have to count the splines on the input shaft.  904 transmissions 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.

Borrowed from: http://www.allpar.com/mopar/transmissions/identifying-torqueflites.html   

[GN]

Nothing external or maybe a stamping? Are the 904 and 727 bolt patterns the same?

[Charger RT]

trans pan edge on passenger side is straight on a 904 and has a bulge at the front of that side by the dipstick tube hole on a 727.
Tim

[RD]

http://www.dodgecharger.com/forum/index.php/topic,61361.0.html