2 Problems at Once? Or Same Problem?

I can't tell if I have one rattling/grinding problem that has persisted, or whether I had 2 problems pop up in parallel.

Symptoms: When taking off from a stop, I hear a grinding noise for ~1 sec that turns into a rattling noise for ~2 seconds before disappearing above 5mph. It happens almost exclusively when the truck is warm and is exaggerated when doing a hard take off (fast acceleration from 0).

Weirdness: the weird thing is I was having a vibrating/rattling problem right before this grinding problem. The vibrating problem was from the loose heat shield surrounding my catalytic converter. I found the solution here: https://www.tacomaworld.com/threads/rattleing-buzzing-sound-from-under-the-truck.284494/ I decided to pop off the heat shield entirely. The rattle was resolved and I was happy.

Or so I thought. After about 2 weeks of no vibrations, I started to hear it again - or at least something that sounds very similar. It sounds similar to the earlier problem, but slightly more like "grinding" instead of "rattling". It sounds like it is coming from a very similar place.

I've looked all around the cat converter and hammered around trying to replicate the sound, but no luck. It is driving me mad! Any thoughts?

 

Are your motor mounts and trans mount in good shape also check your leaf springs and carrier bearing