Board Thread:Theories and Speculation/@comment-25139119-20150930151135/@comment-24949460-20150930170635

Basically Naruto is using SPSM but only using Kurama's chakra(hence the glowing skin). It's when Naruto uses ALL NINE Tailed Beasts' chakra that the none glowing skin/Truth Seeking Balls powered up form of Naruto's SPSM can be used.

Naruto still have the SPSM, it's just that he is using Kurama's chakra only.