Do I have to open up my transmission?

[rgafitanu]

Hello all,
This summer my transmission started to act up. More precisely having a very long 2 to 3 shift and eventually locking into 3rd only after easing up on the throttle. About the same on 3rd to 4th, the difference being that on 2 to 3 the tranny releases the 2nd and starts racing until I ease the throttle almost completely to lock in 3rd. 3 to 4 the engine doesn’t go loose at the shift but it’s hesitant until I ease up.
I checked the modulator linkage motion and it’s good with engine running. On the battery alone with no engine it’s not that solid, battery drops to 11V.
I verified the modulator pressure and it’s a solid 12, 44, 65 PSI on the three positions with a good 17 inHg vacuum pressure (disconnected).
I would be curious to check the pressures while driving and during these long shifts but I don’t know if it would help me. I read the transmission blue book twice and it looks I need to have a look at the clutch K2 sleeve with all that entails.
Anybody has some experience, suggestions or advice?
Thank you for your input,
Radu

[ejboyd5]

Have you checked the level and condition of the transmission fluid?

[rgafitanu]

Level ok and dark red.

[Bshaunessy]

1970 280 SL Automatic.  This past summer was having rough and delayed shifting,much as you describe.
I did the "linkage tour", from the tech manual on this site.   Very minor adjustments required to throttle linkage (1-2mm max, but several adjustments necessary to make perfect per "linkage tour".
  The car now shifts. Very smoothly…like new! 
  COCNCLUDE: the throttle,linkage and adjustment of same are integral to how the auto trans functions…..and the tranny is very sensitive to how the throttle linkage is set up.
  Certainly worth a try for you…30,min with no beer breaks.
   Good luck.

[rgafitanu]

You are right, no reason not to try these simple verifications if there is a chance they can save dismantling the transmission. The last time I did that was 7 years ago if not longer.