My last TS engined car ran very well on 10/40 Castrol GTX Magnatec. Current advice ses to be go for fully synthetic if possible. My GTA runs on Millers CFS 10/60 which is what the weight the manual says it needs. If I had a TS I'd use a fully synthetic oil to the spec in the manual. I like Millers, Castrol and Mobil oils, but that's personal preference.