oil change and LSD rear diff change. flowmaster race series muffler?

So today, i changed my oil using Mobil 1 oil and oil filter, i used royal purple last time and liked it alot so lets see how Mobil 1 does.

I previously read in threads that there was some concern about changing the rear diff fluid on the 05+s with the LSD diff. Well i used castrol 80w-90 with some LSD additive, and i haven't had any chirping or grinding yet, but ill update if there's anything. While i was under my truck i was thinking about putting the flowmaster race series 40 on.. does anyone have any thoughts or imput on this?

 

If it makes you happy...Go for it??

Flowmasters tend to have a better timbre/sound...but they hurt performance a bit. But whatever makes you happy.

 

thanks guys i think ill go for it next week!