[cleveman]

Just scheduled a free tranny diagnostic at a local shop for Thursday... also picked up some lubeguard red, but I'm holding off on putting it in until after the appointment so that the tranny guys can get a good look at it without the problem being masked by the lubeguard.

Another note that I found interesting - the problem seems to go away competely (or get far less noticable) when the A/C is turned off. I drove around for 2 hours yesterday looking for the lubeguard, and purposefully left the A/C off and couldn't get the shudder to occur, even when I TRIED to re-create the circumstances that are causing it.

does that suggest it's not the tranny at all? or could an electrical problem be CAUSING a tranny slip, somehow, maybe by sapping power from the hydraulics or something?