Ramasaur

Anyone use this yet. I've heard good things...so on my last oil change, I filled with RP. The first thing I noticed is that the engine seemed quieter, next was that at cruise (70) my EGT's on Level 3 are normally around 750. After RP, I'm only at about 600? Would the synthetic cause the engine to run that much cooler? I normally run Rotella 15W40.

Mark Thomas

Synthetic means less friction, less friction less heat. I used to run Royal Purple, but switched to Rotella 5/40 synthectic

SuperGewl

Yes, less friction means less heat so it should alittle cooler. You should have also noticed that your RPMS at 70 were less than before the synthetic because of less friction. You may have also noticed that your normal oil pressure is also less thatn with dino oil. Don;t worry as long as thepressure stays in thenormal range once it's warmed up.
All of these things normall equate to better fuel mileage, however do the engine running quieter you will have the tendacy to go faster so you offset the fuel mileage gain by the better feel of power

RustyJC

Sorry, synthetic lubricants may have a number of advantages, but this isn't one of them. RPM's at 70 MPH are fixed by the gearing in the transmission and rear axle. Assuming the torque converter is locked up or the clutch is engaged, RPM's at any speed will be a function of transmission ratio, rear axle ratio and tire diameter. The BHP produced by the engine, its internal friction, sign of the moon or any other factors won't change the RPM at a given speed.

By the way, I'm using Royal Purple in my Acura 3.2TL-S and my wife's Durango 5.9L right now and am pleased with its performance.

Rusty