Monday... 12000 miles and switched to:
LE 607
original diff fluid was really dark... and only a little metal in drain plug

after a couple miles... I beleive it working a little easier.. the old
but dyno...it seems better

Wednesday.... 12200 miles and switched to:

The trans fluid was not that bad...

There was alway a little bite going into 2nd gear... just a little.. and post I have read here said its quite common

Now with GM-Tans. Fluid FM #12377916.... it seems like glass
smoother than any tans I have shifted
22 years of driving

I highly recommend making the switch if you like giving your car the best care

I my car