I refilled with 5w-50 since it's a track pack car. I prefer to keep to manufacturer spec. Also used a FL 500 Motorcraft filter. Filled the filter before installing as well.
I'll be reverting back to stock this afternoon to see if anything changes, then hunt down loose plugs if nothing seems to be better.
2013 GT Premium, Brembo's, Track Pack, 6MT, Recaro's, Reverse Sensors/Camera, GT500 A/B, BMR Springs, Strange 10-way Adjustables w/GT500 Mounts, BMR Adjustable Panhard Bar, 20" Staggered Vossen CV2's/Nitto Invo's.....BMR UCA/Bracket, BMR LCA's, BMR LCA Relocation Brackets being done soon.