Musclejunkie

I'm totally confused! Last I checked, this engine is still classified as an internal combustion engine and has cylinders, pistons, crankshaft etc. Why for so many years did auto manufacturers suggest changing the oil after break-in? Usually 500 miles. Do motors no longer require break-in? Or have they ignored this now in favor of premature engine failure and costly replacement down the road? Granted, I'm old school. I do like the synthetic oils and will change every 5,000 miles - screw the manual.

koolponycar

I went to bobtheoilguys website, pretty interesting on how oil thickens when it cools, so it would seem we need a oil that will be less thick on startups, that is where most normal wear will come from. I noticed that Royal Purple was not on his personal favorites list, but Renewable Lubricants was his 20 grade choice in full synthetics. Royal purple wasn't even mentioned, I don't know why? But like nuke said, pick one with the right interval and a QUALITY oil filter and all should work well.

Funster_2011V6

Hey, guys, I've done some more reading and I think things may not be as simple as I stated earlier.

I got caught up in the debates on oil forums about the 5w30 vs 5w20 thing being a move by automakers to better meet CAFE standards. While I still believe this to be partially true, after more research I've decided against 5w30 for this motor.

After switching to heavier oil I have been seeing higher oil pressures and I'm not sure that this is good for my particular application. Let me explain.

Our vairiable cams "vary" by use of oil pressure, right? If true I'm concerned that changing the oil pressure can change how much the cams advance. Since Ford is requiring 5w20, they may have calibrated the engine accordingly, the cams may not phase correctly with the heavier oil and higher pressures it generates.

Since it's only money, I drained my 5w30 RP and put in the 5w20 instead. The valvetrain is just as quiet, but the car seems to have better throttle response.

Also, since I have the cai, I can hear a change in the intake sound at the top of the rev range which I attribute to full cam advance. The sound I hear went from 6250+ rpms to 6600rpms+. Nothing else changed but the oil viscosity.

If I'm full of crap, so be it. But i'm gonna stick with the RP 5w20.

Sorry for the long post.

JAJ

Hi! I'm a new guy here, but I've been a BITOG member (BobIsTheOilGuy) member since 2001.

There's a set of interesting articles from Dr. A E Haas on the BITOG website that might clarify the 20 weight vs. 30 weight discussion. He has a passion for cars and considerable fluid dynamics knowledge and skill. He runs xw-20 oils in his his wife's Lamborghini and both of his Maybach's (even the AMG one) but he does step up to 0w-30 for his Enzo. He's putting his money (lots of it) where his mouth is when he recommends using 20 weight oils in cars even when the oil specified by the engine manufacturer are much higher.

It's an interesting counter-point to the "heavier oil is better" conventional wisdom. His view is that engines last better if they run cooler, and thinner oil flows through bearings faster and that cools the engine better.

6+6 Stang

you be da man funster...i always liked the 5 20, just curiuos, is the purple safe oil....always been a mobile1 man, but since you say rp is one of the few 100% synt, i would like to try.

Musclejunkie

Good information...Thanks! If Ford wants 5w20 then that is what my car is getting. My previous high rev engine had 100k on it and didn't burn one drop of oil and was quiet as a church mouse. I used cheap standard grade Valvoline 5w20 and changed it every 5000 miles. The quicker it flows through the engine the cooler it runs makes a lot of sense. I appreciate all the discussion on this. I will use full synthetic on this car. I ran Mobil 1 in a new Vette and had gasket leaks. Not sure if it was the oil, but I don't trust that oil. I'll try whatever Ford recommends for brand even if it is Motorcraft.

SteveMasterZerox9

What about motorcraft fully synthetic 5w-20. Would you say thats more like mobil 1 fully synthetic or closer to royal purple fully synthetic. Ive always used motorcraft over mobil 1 and new of the benfits of rp but not sure if its worth it over ford quality.

JAJ

After all those years as a BITOG member, I've concluded that all of the branded engine oils that meet API and ACEA specifications perform very well. Motorcraft oils (synthetic and conventional) - made by Conoco Philips - are well thought of by the BITOG crowd. They're in the same league as Pennz, Mobil, Valvoline, Quaker State and the rest of the "big" brands. Oil analysis results reported over many years support this good reputation.

Motor oil marketers, particularly of the smaller brands, tend to try to focus our attention on how they make the oil they sell, rather than focus on performance. Once you get past API SL (to SM and now SN) modern addititive chemistry is so effective at prolonging the life of the oil and controlling wear that the differences between conventional oil and synthetic are almost undetectable.

The only time synthetic outperforms modern conventional oil is under high heat conditions (extended periods of 230 degrees+ operation) or long drain intervals. Most of us never see that. I do because I run at open (road racing) track days and engine oil sits at 230 to 240 degrees for hours at a time (in my current car - my GT is on order). Even then, I use the manufacturer's recommended oil and change it once a year on the manufacturer's recommended schedule. I have the used oil analyzed when I change it and my the oil analysis says everything is just fine.

Back to the original question: the bottom line is that you can use Motorcraft oil with confidence. Will it perform as well as RP? I have no idea - RP has almost no "presence" on BITOG. RP is API certified, so it's going to perform well. Is it better? It might be, but its unlikely that any of us, including me with my open lapping days, will ever face conditions where its superiority will be detectable.

OlPal

Excellent Post 6+6, that's why I joined this forum, to learn from Folks like you.
I'll be creating Ford Owner Account tomorrow.
It'll be hard for me to go 9,000 miles on a brand new engine, especially since that'll be like 2 years for our 'Stang...
Thanks Again !

J7erry

I went to the dealership at 500 miles for a break-in change, and they told me they don't need that anymore, that they run and drain them at the plant. Don't know if that's true or not, but I waited to 5k. I'm a firm believer in not going over 5k, and I'm religious about getting it changed. It took me a while to go from 3k to 5k, but I assume they know what's right for the car, but I can feel a difference after an oil change. Just my 2 cents.