I know this is the only stuff to use on the old rovers but here is my question. I know I can order it through AB, but a little harder to find at auto stores

. I used to buy it at napa but don't have any close any more so I will be checking there soon. I finally came across one that carried it (pepboys) but it has switched to a synthetic. Looking at the bottle it says its been reformulated so I am not sure if this is all they offer now? If so is the synthetic fine for the rubber in the system, or should I just order the older stuff from AB

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