Oil Drip on T50 Gearbox when Driveshaft Pulled Out, Normal?

[ballpencil]

Hi,

Sorry for the lengthy post.

My car is a Daihatsu Charmant which shares many resemblance to AE86 SR5 (4AC powered).

I just converted my rear diff from S-series to T-series. I understand that i need to shorten the tailshaft since T-series diff nose is longer. Without shortening, the tailshaft is prone to bottoming to the gearbox output shaft.

However, i was able to bolt-in the standard-length tailshaft to the diff (no shortening done yet) but i can hear some metal-to-metal grinding sound when i drive the car. Afraid of actually bottoming already, i unbolted the rear tailshaft-pinion bolts and found about 10-15mm of play before the tailshaft bottoming to the gearbox.

I then proceeded to pull out the tailshaft from the gearbox output and surprised to find some oil dripping suddenly. It was only for 5-10 minutes and stopped.

Qs:
1. How much do i really need to shorten the driveshaft? 25mm enough?
2. What's the grinding sound i hear when the car's running? Suspected it was the tailshaft bottoming but i still have some 10-15mm of play!
3. Was the oil drip normal? Or have i damaged my gearbox oil seals? No more drip is found now with the tailshaft still off.
4. Related to #3, the rubber seal seen first when you look at the gearbox output shaft. Is this oil seal or only dust seal?
5. Must the gearbox be split open to replace, if any, damaged seals?

[tojo]

1 measure difference of the diffs
2 probably bottoming
3 Thats normal
4 Oil seal
5 No. Easy to change. Even easier if you knock off splash protection on the end of gearbox first

[ballpencil]

1 measure difference of the diffs
2 probably bottoming
3 Thats normal
4 Oil seal
5 No. Easy to change. Even easier if you knock off splash protection on the end of gearbox first

sweet! short and straight to the point! just what i needed.