Royal Purple Oil Experiment

[Nicholas47]

I put Royal Purple in 6,000 miles ago. I'm changing the filter only tomorrow, and at 12,000 miles I'm going to change the oil and filter. I'm going to send the oil somewhere to get analyzed.

I really regret not sending in my last oil to have something to compare it too. It kind of made it a shitty experiment. But if it comes back solid, it mean I have nothing to worry about, I suppose.

That is unless anyone has anything to say that thinks this is absolutely not a good idea.

I'm at 212,000 miles on my supercharged 3.4.

 

[ThorInc]

I assume you will top the oil up after the filter change?

 

[coleb10]

RP oil

This is the same way my friend does his oil except he changes the filter at 5,000 and tops it off. Then the next oil change is at 10,000 miles. He is the one who got me to start using Royal Purple years ago. His experience is with Formula 2000 race cars and being a former pit crew member for a NASCAR truck. Worked out well for him so far on his daily driver too.

 

[MKERunner]

So this ended up longer then I meant it to be, but I hope the information helps.

Honestly I would trust any name brand synthetic oil with this same procedure. Modern oils have enough detergent additives to allot for extended oil changes. I used to average 500-1,000 miles per week with my job and regularly changed at 7,500 and above. Use a quality filter and you won't have any problems.

Unless you're using a non-api rated oil there's a limit to the level of friction modifiers - ZDDP aka zinc - allowed due to emissions regulation. RP isn't a bad oil by any means, and some oils will have higher zinc levels than others, but anything right off the shelf isn't going to have a huge difference between each other, including the "high performance" oils. If it has the api donut, it has to pass the same regulations.

One trick is to actually look for oil bottles that have been collecting dust. the api designation is updated alphabetically, so "SL" is older then "SM", and older then the current "SN" designation. Anytime a new letter is used, just assume that less zinc is present in the oil, you may get lucky and find some old stock.

Source; I used to sell dedicated racing oil and went through multiple training seminars with a certified lubrication specialist (which is an actual thing).