transmission sluggish to shift down

[finch1240]

I have a 2001 ranger XLT extended cab V6 4L 4X4 automatic. Sometimes when I slow down the auto transmission seems to be sluggish to shift down and lugs the engine a bit before it pops into the appropriate gear. The engine died on me once after I came to a stop, but it started back up like normal, it seems like this might have been to blame.

Any idea how to fix this?