I just recently switched over to Valvoline VR - 1 10-30 racing oil for the zinc up until then I was using a zinc supplement but unfortunately they quit selling it. I would prefer using a supplement and going back to Castrol GTX oil.
Your reply planted a seed in My head. When I got My '67 Formula S in 1984, It was used for road rallying up till they gave it to their Daughter. The Trans input shaft bearing went 6 months after that and i got it. Weird Bearing size, No one had a bearing for it. I shimmed and ground the OD of a Marine bearing to fit... They were serious about the car, and one of the things they told Me is that they ONLY used Castrol GTX 10-40 oil. I've continued that, but haven't run the car for 15 years. Been stored. So thanks, OUTLAW. That's what I'm going to do. Same good oil With ZDDP additive. Guess I'll order up a case of ZDDP on line, and run all the old Iron with that. Thanks again, C300 :cheers: