anwered by: canteau
It depends on the rear shock, a Rock Shox Monarch for example uses a 3wt suspension fluid along with 15w50 lube.
15wt suspension fluid is different that 15w50 oil. The 15w50 is going to handle higher pressures and temperatures that the 15wt fluid and can not be interchanged. We do carry the 15w50 lubricant and it can be found here:
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