Have a 2018 Mustang GT A10 PP with Procharger P-1X running E85. Bottom side mods are; Driveshaft Shop carbon fiber 1 piece drive shaft, Driveshaft Shop 1400 HP rated axles, front is lowered 1" using Ford Performance street lowering springs, OEM springs in back, Viking Warrior shocks in back set at 4 compression & 10 rebound, Steeda stop the hop package including rear lower control arm spherical bearings, Steeda jacking rails, 17x10.5 Bracket Racer wheels mounted with 305/45/17 M/T ET Street R tires. All of the above mods were installed at the same time with 1500 miles on the clock. In stock trim I made nine 1/4 mile passes with no noise from ring and pinion. After installing modifications I didn't even get through the tuning process, Lund, before the noise started. The noise increased exponentially after making three passes at the track. I'm talking loud, like you can not carry a conversation with someone in the car. Replaced ring & pinion, bearings, seals, etc. put 350 easy miles on the car with no noise. Made three passes at the track and the noise is back! It's hard not to think that one or more of the after market items are causing this. Really don't know the best place to start to isolate the issue. Has anyone experienced or know someone that has experienced something like this? Any constructive ideas?