1st gear shudder from overfill or just age?

[Gearhead Otaku]

2001 Ford F-150 5.4L with 150K miles. For about from 0 to 5 mph or so there is a grinding shudder, not super harsh but slowly getting worse overtime. Realized today that it seems to have been slightly overfilled as the entire white plastic tip at the end of trans dipstick is red but no further up than that (fluid stops just before touching the bare metal above the plastic tip). I imagine this to be 1 to 2 quarts above the needed amount. I bought the truck with 100K and put 50K on it myself - dealer must have overfilled it. Should I be worried or is it like a normal thing with these trucks to shudder in 1st gear as they age?

 

[Astro14]

The first step in troubleshooting any transmission issue is to be certain that the fluid level is correct. Most transmissions are very sensitive to the correct fluid level, so well I don’t know your factory procedure, make sure you get that, right.

If that is right, most transmissions benefit from fresh fluid. Make your second step, if needed, a fluid change.