Just had differential carrier replaced

I'm driving a 2018 trd OR 4x4 MT with about 25,500 on the odometer. Ever since I bought it, new btw, it has had a slight clunk in the driveline when going first to reverse or vice versa. It kind of sounded like a worn out ujoint. I couldn't feel any slack by twisting it, neither could the shop at about 5k miles.
At 24k miles of relatively easy, mostly highway miles the rear end started howling when I left off the gas. It was especially noticeable going downhill.
By 25k it was a good bit louder. I saw there was a tsb for something similar so I mentioned it when it was in for the fuel pump recall. They installed the parts kit but it didnt fix it so they drained the diff. The oil was full of metal. The magnet plug was covered in filings. They were very cool about replacing the diff carrier. Gave me a nice loaner for the week it took for parts to come in.
Now its quiet. Anyways, if you have a clunk in the driveline might want to get it in and get it checked out.

 

They tore it down and replaced the just the carrier?

 

Yeah, it seemed to be a modular bolt in assembly. The ring, pinion and all the guts.

 

He's not using the right terminology. Sounds like he means the 3rd member.