How can one fix a loose transmission dipstick tube on an 2001 Ford F150?

You can start by pulling the dip stick housing out, then putting some rtv black silicone around the bottom, below the bubbled out part. wait about the time it takes to smoke a cigarett and put it back in the tranny. Now most of the dipsticks bolt in with one of the tranny bolts, you may need to check to see is it has come loose or even maby broke loose. In this case you can ether quick fix for now by using a zip tie, and tieing it to something close by and stationary or replace the dip stick housing.