I have a '73 valiant with a 225 slant and a torqueflite automatic.

The torqueflite shifts just like it is supposed to. Nice smooth shifts at the right speeds. Only just a little noise in first and a little "clunck" when shifted in reverse. About six months ago I changed the filter and filled it up with dexron II.

Now I noticed that after driving at speeds of 60-70 mph for an hour or so, the shifts get a lot firmer. I do not know if it did this before, because I rebuilt the engine and i didn't drive it for a while. Does this indicate a problem? Or is this normal for this transmission?

Roelof