long time reader...first time poster. Just pickup some royal purple for a upcoming oil change and noticed a few new things. It now meets GM6094M and dexos1 requirements but I also noticed no where on the bottle does it mention their synerlec additive. Have they changed their formula and pawning the old formula as their new HPS oil that still has synerlec in it?
RP has changed their lineup.
The normal RP sold at Advance Auto and other places is the new AP SN formula that does not contain any Synerlec because it cannot be used and meet SN standards. They are in switchover right now, so you can tell the difference by the bottle style as the new SN has the new bottle design (as does the new HPS below)
They have added a new oil the High Performance Street (HPS) that still contains Synerlec and higher levels of ZDDP (around 1200 ppm). This oil has been reformulated with more Synerlec than the previous "normal" RP (I got this from the RP tech line). In addition the under 40 weight oils had the ZDDP increased to the 1200 ppm ZDDP rather than the 1000 ppm previously used to meet the SL standards. The 40 and 50 weight oils previously and still have 1200 ppm ZDDP
The XPR (extreme performance racing) line is unchanged as far as I know.
Hope this helps