Royal Purple
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Go to powerstrokenation.com and go to the fluids/oils/additives section and read. The most recent that comes to mind was a guy who tows quite often with his truck and was trying different differential fluids. The RP performed just terribly on the oil analysis. Shaeffers and Amsoil were among the best.
There is this.... It is linked on amsoils website for obvious reasons, but still a good read...
http://www.amsoil.com/lit/g2457.pdf?=zo1466322
There is this.... It is linked on amsoils website for obvious reasons, but still a good read...
http://www.amsoil.com/lit/g2457.pdf?=zo1466322
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