I just finished changing the 5th gear ration in the T5 that I have in my little "modified" street roadster and can see why they have a "fragile" 5th gear. The box must have been originally designed as a 4 speed and then they put 5th gear in the tail housing, this was done by making a splined extension on the countershaft and extending it into the tail shaft housing, they added a gear on the mainshaft along with the require syncros and shifting mechanism and now it is a 5 speed except the gear that is now mounted on the added snout of the counter shaft is only supported on one side by bearings so if you have some real torque you will break this snout off. If I were going to use a T5 I would take the 5th gear completely out and use it as a 4 speed as the other gears are pretty stout and 4th gear is straight through.
A note regarding the T5, there is a version that is used in 4 wheel drives that has a short output shaft and a flanged rear tailshaft housing, my bet is some one could pretty easily make an adaptor and coupling that would allow you to mount a T5 directly to the input of a rear end and have a pretty compact package. Good for streamliners and lakesters.
Rex
Rex, my T4 for my tudor is just that. They came out before the T5 and are neat trannys. Even looked at using my T4 in the lakester but think I decided against it
