Rear diff being replaced 3k miles

I have had a WRX and a 02 z28 which both had some driveline noise. I'm not going to go crazy paranoid over the vehicle. I'm sure Toyota will try to make good if there is a larger problem down the line. I was reading some other posts about some additional bracing in the later Tacoma frames. From modifying the two vehicles that I had previously anytime there is an additional bracing such as motor mounts, trans mounts, subframe connectors and what not there was always additional noise. Just a theory.
There is obviously an issue with some of ours though that was not normal.