Fluid drained out of tranny, and I started the car, and shifted back and for for about 15 minutes before I realized what had happened. Fixed the issue with the pan, and refilled with fluid.. It works, but is sluggish when starting , especially when backing. Fairly certain I got it hot..Are there any additives that will bring this back to its old life???? Car has 147,000 miles and ran beautifully before this..