Motor Oil

August 17, 2018

Is HMX® different from your API-licensed engine oils?

Yes, HMX is fortified with Royal Purple’s proprietary Synerlec additive technology as well as additional seal conditioners beneficial to higher mileage engines to maintain elasticity of […]
August 17, 2018

Is a special oil filter required when using Royal Purple?

While no special oil filter is required, we do recommend upgrading to a high quality oil filter. A high quality filter will prevent contaminants from circulating […]
August 17, 2018

Can your oil be used with flat tappet cams?

Yes. For stock, non-performance valve trains, Royal Purple API-licensed oils (API SN and ILSAC GF-5 licensed) are OK. For upgraded performance flat tappet camshafts, and vintage […]
August 17, 2018

Do your motor oils contain zinc/phosphorus?

Yes. All Royal Purple® engine oils contain the zinc/phosphorus compound zinc dialkyl dithiophosphate (ZDDP), but the maximum amounts are restricted by the current API oil specifications. […]