Originally Posted By: BlueOvalFitter
Back when synthetics were not very popular and the consumer had very little knowledge on them, what were they using in their turbo equipped vehicles? I am going to go out on a limb here and say, dino?
I know, oils have evolved leaps and bounds since then but why not dino, even at a short OCI? And more specifically, why not a 5W30?
I had a 1985 Pontiac Sunbird Turbo which I bought new. For its first year or two I ran Valvoline Turbo-V, which was a conventional oil that was specifically formulated for turbos with reduced VII content. It was available only in 10w30 if you wanted a 30-weight. (IIRC, 1985 was a LONG time ago! Maybe they also had a 30 monograde.) I autocrossed and tracked that car almost every weekend from April to November every year, and didn't have a lubrication-related problem. (I did lose one turbo when the snap ring holding the bearing cartridge to the turbine housing failed, which was certainly not the oil's fault.) I held OCI's to 3000-3500 miles. But Valvoline Turbo-V became difficult to find, so I switched to M1 and never looked back. Most of the time I ran the 5w30, but occasionally ran 10w30 when 5w wasn't on the shelf. I traded it in after 14 years and 166k miles, and the engine wouldn't burn a drop of oil in 6k miles.
