928 oil additives
#16
#18
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Not sure why but I suspect that ZDDP is a liquid and the metals in Restore are particulates. I still haven't figured out why the zinc was reduced in motor oil since it has been used with cats and O2 sensors for over 30 years without harmful effects.
Dennis
Dennis
#19
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Precision is using a zinc additive at oil changes now since oil manufacturers are removing most zinc from the oils. They also used a bottle of something for lifter noise once but I am not sure what its called.
Come on Ron, find out we need to know!
Come on Ron, find out we need to know!
See Greg's post #13 in this thread: https://rennlist.com/forums/showthre...highlight=zinc
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#20
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I'm surprised I haven't seen more talk of the ZDDP issue here, just the reference to the 993 site and Pelican 911 BBS, where there was a huge discussion.
I switched to Brad Penn 20W50 in my GT (PO was using M1) and RP Max Cycle 20W50 in my 911, but will switch to Brad Penn in that as well at the next change. RP is good, but too pricey for the benefit IMO. You can find Brad Penn on Ebay for about $50/case.
I switched to Brad Penn 20W50 in my GT (PO was using M1) and RP Max Cycle 20W50 in my 911, but will switch to Brad Penn in that as well at the next change. RP is good, but too pricey for the benefit IMO. You can find Brad Penn on Ebay for about $50/case.