Mark Thomas

is it any good or should I say better than delvac 1?

turbo thom

All I know about RP is it has a pretty name. For me, my oil starts with the letter A_____L <br><br>..Preston..

Lightman

D1 is king!! ;D I'd say Amsoil series 3k 5w-30 is just as good also, but in a 30 weight. I prefer D1, because it's 5w-40. A close second is the amsoil heavy duty diesel and marine 15w-40, and much more reasonably priced. I've heard scattered things about RP. Same with Redline...

Cat Cracker

I have Royal Purple in mine now...I won't even debate on whats better...my truck hasn't seized up do to lack of lubrication. I will also note that I work at an oil refinery, and in every compressor, pump, and turbine we run Royal Purple, and haven't had any oil based equipment failure yet. So, with that said; Its all good...use what you want, just change it every once in a while... <br><br><br> Cat Cracker

shaft

I'm curently using RP in my current trucks, boat and in all my previous vehicles. I have a friend that used RP in his racing boat, busted one of his oil lines and lost all the oil from his motor. Checked the internal parts for damaged and interestingly enough, no damaged has occured. That my friend should answer your question. I am very please with RP's performance. The more you bomb your motor, the performace gain you're going to get from RP.

wick

I did not think that Royal purple made a Diesel compatible oil. I use to run Royal Purple in my rear diff of my race car. <br><br>Left the engine oil to Valvoline 20W-50..

4x4

I run it in my axles and ps.