Took my newly acquired R wagon with 49.9K miles on it for a run today and noticed for the first time when I stopped at a light, that there was not the smooth transition down to first just before you stopped. You could feel something akin to a roughness as it changed gears as you came to a halt. Small, but noticeable. Accompanying that was the engine rpm fluctuating just a little bit before settling down. A block from home I slowed to a stop several times, but each time the engine and transmission transited smoothly to a stop with none of the above symptoms. The fluid is burned and definitely in need of a change, which I plan to do shortly. But I wonder if this is symptomatic of other causes, like a PNP switch getting ready to fail, an O2 ready to quit, or some sensor ready to fail or indicating a potential problem. Would like to be on top of this one before it happens. Hoping that flushing the transmission and refilling with Mobil 1 ATF will cure the intermittent slightly rough downshift and surging idle, but I know enough from past experience working on Volvos not to get my hopes up. Helpful comments, please. Dick