I've been noticing that even after having had the valve chains and tensioners replaced, there is still a whirring sound coming from somewhere in the power train when the car is cold. It goes away after it warms up and heat soaks. The noise is more prominent when accelerating from a stop in a right turn, and when it upshifts and rpms decrease for cruise after speed is reached. The techs at both the dealer and the indy shop have told me it's coming from the transmission, that it is likely cold fluid having difficulty passing thru some tight areas in the tranny. The Jag tech told me he has heard of this before, but didn't know exactly what it was.

Anyone have any experience with this?