Transmission slipping?

I have a 1992 XJ 4X4 4.0 with AW-4 auto trans. When traveling in "D" at constant speed of about 60 mph under modest load I see about 2K RPM. When I shift from "D" to "3" the engine spins up to about 2600 RPM, holds this for maybe 5 or 10 seconds, then spins down to about 2200 RPM, which it holds thereafter. I can get it to drop from 2600 to 2200 a little sooner if I back off on the gas.

Is this normal behavior for the trans?

Thanks!
Mike

If you are staying at 60mph and shift to 3rd, then yes your rpms will jump way up. If your rpms is dropping down while still doing 60mph is strange in that with the lower gear rpms should climb and stay there. If the clutches were slipping it would raise rpms not lower. 2200 rpms in 3rd doing 60mph in my jeep will get me above 3000, stock rear end with 30's. In drive it is close to 2k though. How is reverse ? I say this because almost every tranny I toasted in my youth, the reverse was most evident of tranny slippage before death.

The AW-4 has a 'lock-up torque converter. My guess is that after shifting to "3" this torque converter is not locked so I see constant speed with engine at 2600 RPM. After a short time I guess the lock-up locks which I guess explains the drop to 2200 RPM. So what I experience could just be normal transmission operation. However I would expect a shorter time to lock. Just wondering what others experience.

Haven't noticed any issues in reverse.

I believe you may have answered your own question. That is the same explanation I would have given. Not that it is correct, but it sounds logical to me, makes sense. From my experience, when an auto starts to go, they always began revving up a bit before falling into a forward gear with the tranny in drive. Shortly thereafter, Reverse would follow. Then if left ignored, it would gradually get worse until it failed.
I learned though, that if I gave the car to a buddy of mine who knew how to rebuild the auto tranny's, he would make some adjustments, not sure what, but the shifts would be quite a bit harsher on engagement, but the 'revving up' would stop for quite a few months to almost a year on one occasion, buying me some time to prepare for the impending rebuild.
Buy a used AW4 from a boneyard and take it apart. Analyze the parts and how they come apart/go together. Buy a rebuild kit, and give it a try. With a good manual on auto trans rebuilding, its a great way, and fun, to learn how to rebuild them.