transmission slack?

could be it's dropping in and out of od.

You might want to check the fluid level, condition, and strainer (if the car has one). Low fluid pressure or insufficient fluid first come to mind.

Some mechanics just clean the strainer, it's best to change it out because compressed air can't do an effective job. For example, Fram ATF kits are about $20 each. I think that car uses Type-IV (?) ATF? Don't substitute another fluid (or maybe that was the problem from the last ATF change?)

me wrote:

== Not sure this has relevance to your case because I had more like

150,000 miles - but after replacing the axles, ball joints, and control arms, I noticed a significant reduction in the phenomenon you describe. Used to bother me, and I don't even notice it at all now. I think the axles made the biggest difference. (incipient cracking at one boot and slight persisten seepage at a clamp on the other) There was only a small amount of play in one ball joint but the Factory Service Manual says allowable play is zero, so I changed both. They also describe the procedure for checking where you lift then lower the car half way and use a pry bar from beneath against the inside of the wheel. In changing the ball joints, I noticed cracking at the rear bushing for the control arm, and when I found a clever way of levering down the control arm to make the steering knuckle easier to reinstall, I think I tore it more - thus I replaced the control arms. After changing the ball joints and control arms, I noticed a vibration under load at very high speed disappeared. I wonder how many rear control arm bushings are suspect because when removed it I could see the rubber collar had split all the way through on both sides but you could only see some relatively minor surface cracking when the control arms were in the frame even with the wheel and axle removed and using a shop light looking directly at the area. This is an odd kind of bushing, it is under tension continuously and pivots diagonally so it doesn't just insulate metal to metal rotational contact but is an integral part of the control arm geometry. Doubt that is your problem with such low mileage though. The conventional wisdom on drive line slack most likely due to play in the half shaft axle CV joints, is wait until the boots show cracking, then replace. So you can safely ignore it. It is recommended to press on the boots with the car in the air though, to see if they're cracked inside the creases. With a newly acquired vehicle I'd also check all the fluid levels and condition to insure some neglected item isn't contributing to an unusual condition.