904 no second gear

[TheCraigMachine]

My 69 model 904 completely lost second gear the other night after a few sluggish feeling 1-2 shifts. Still has first, third, and reverse, but second just freewheels. Looking at the sequence of operations on the trans, its obvious that the kickdown band isnt applying, but as far as I can tell, the rear clutch pack should remain engaged even if the kickdown band doesnt apply on the front drum since the rear clutch pack stays engaged any time the trans is in any forward gear. This should cause the trans to more or less stay in first without shifting into second after the shift point has been reached. The way I understand it, the only way I could be losing BOTH the front band apply AND the rear clutch apply is through a massive pressure loss via the kickdown servo, like maybe a blown O ring???
The only mods to the trans is the addition of a TF-1 kit.

Needless to say, im about to start a rebuild. Just wondering what problem I should be looking for on this thing.

 

[Hipo65]

Broken strut for 2nd gear band possale?? drop pan & see if its layen in there.

 

[fishy68]

There's no O-ring on the front servo but it does have steel sealing rings. I haven't ran across a case where they were so bad they caused it to lose pressure all together. I also haven't ran into a broken front servo piston but it could happen and that would cause a massive pressure loss. Since your rebuilding it I think you'll find the problem in the front servo area. If you don't have it out of the car yet I'd check the front band adjustment. If the adjuster screws all the way in with no tension it's possibly a broken front band strut like Hipo said. Have also seen them fall out when the band was way out of adjustment. Even if you find the band strut good I suggest replacing it with a HD strut when you rebuild it. There's a lot of pressure on that little piece of steel even with a stock trans. When you add a shift kit it gets slammed even harder. I also suggest replacing the rear servo with a billet piece cause stock servo's are prone to cracking