My 89 240 AT recently started having a problem engaging into drive or reverse when I start out or when I come to a stop, it sometimes takes a few seconds to engage, but once moving along it appears to move through the other gears fine.

I recently added almost a quart of ATF (perhaps I neglected to top it off after changing the water pump and losing fluid via the radiator/cooler, bad!) Nonetheless it still appears to be having this problem... I just checked the level (while cool), and it shows max on the cool side of the stick..

As an aside, I think I'm hearing some kind of air/whoosh/vacuum sound near the shifter, not exactly certain when I heard it (starting/stopping, etc), but I do hear this periodically.


Last but not least (while we're on the subject), I'm curious about the mechanism by which the transmission disengages when the break is depressed, is their a direct connection between the break (vacuum, hydraulic?) or is it related to the engine RPM?


Your help is greatly appreciated (and my apologies if this is already addressed elsewhere in the forum, I gave up after searching around for about an hour and only found one entry pointing to the level as the possible culprit)