Older SL Valvoline Conventional 20w50 ZDDP

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May 2, 2008
Midway, Ky
I found an Advance Autoparts that had a huge stockpile of SL Valvoline 20w50 (copyright on the bottle was 2001, it's the older red, white, and blue design bottle). I have a 71 MGB that I am planning on running this oil in. Will it have enough ZDDP for this engine? Does anyone know what level this oil has?

It's a bit thick for that little engine, and you will feel the drag.
Anyway, a modern SM oil will be just fine in your engine.
Why do you think you need extra zinc? Because it has pushrods? NOT!
Hurst - This lubricant was popular with many people racing older cars - it had/has a following and was a good product in its intended application

BMC engines (A B and C Series) of that era do benefit from a ligher "cold rating" lubricant such as 10W or 15W. This is more to do with the type of oil pump used than any other factor. The same applies at the top end of the temperature scale especially if an unregulated oil cooler is fitted. A 10W-40 would be a great choice if the engine is in reasonably good condition
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