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Sythetic VS Regular 5W30

No crap. Oil is oil...as long as it is good, new oil when you change it...it doesn't matter.

Only issue is when you have a older car and you try to run synthetic...it'll leak because the gaskets are used to the thickness of the dino oil...and the synthetic will seep right by.
 


RP is great oil. Whoever is saying otherwise should have oil analysis done on their favorite oil, and then some done on RP after the same period. The difference is clear. RP's molecules resist shear and breakdown for a much longer period giving great lubrication and protection. This will be seen in the viscosity of the oil after so many months. As the molecules break down the oil gets thinner.

The whole "oil is oil" argument is from the uninformed. Sure, whatever crap you find on the shelves at autozone or whatever is all the same, but there are much higher quality oils out there. Just on the Impala I noted another 3MPG on the highway during my regular commutes just from the switch. I also noticed it took longer to warm up in the winter, despite having a new thermostat. Less friction, less heat, less loss, more MPG. People should have oil analysis done on their oil to see what is really going on. Anyone who thinks dark oil is bad and should be changed knows little about it.

The 3k mile interval was established a long time ago when we were using oils that lacked sophistication of even the crappiest of oils today. SAE certifications put modern oils worlds ahead of what brought around the 3k mile interval. An oil analysis done on even the cheapest of oils shows that most cars can run it for 6k before requiring a change. More expensive oils have better shear strength and will last even longer before breaking down. Something else key to look at for an oil though is its detergent properties. Synthetics have better detergents which fight and absorb acids created by the engine (rich conditions cause fuel to be mixed with the oil). If you never let your car warm up in the winter to evaporate fuels, it will turn to acid and overwhelm the detergents, so now you have some acid mixed with your oil. The detergents in the synthetics are that much better at offering your vehicle protection for extended intervals.

I change my oil twice a year, with some exceptions thrown in for higher mileage. I have an analysis performed each change to spot any early issues that could come up and see how I'm doing on my intervals. Each report says it can be left in longer, by up to 50% more than what I left it in for. I actually save money by using a better oil with fewer changes and my engine is better taken care of because of it. Plus, less used oil for the world to deal with. People who change their oil 3 months/ 3k miles blindly without knowing the condition of the oil are just pissing away money.

I'm not saying take my word on any of this. Do the research yourself. A few weeks before you'd normally change your oil, take a sample and have it analyzed. You will be surprised at how much longer you could go on that oil.
 
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That...is a HUGE waste of money...I'll save the $50+ and buy crap oil thank you...because in the end...its still the same stuff.

Take 2 brand new cars alike, run one with cheap conventional oil and the other with really good synthetic after 100k miles tear down the motor and there will be a difference in wear and tear, sludge build up, etc etc.
 
I know all oils are NOT the same. All of the off the shelf oils don't have any anti friction modifiers anymore because of the EPA. My machinist prefers I use Brad Penn for flat tappet engines and Schaeffers oil in my roller motors.
I run Brad Penn green oil in my GP because I don't have a catalytic converter so the ZDDP can't ruin it.

The fact is royal purple is garbage oil I've seen more scored bearings and spun bearings when people use it. When it gets hot it turns to tar. Its not much of a problem in our cars cause the motors aren't working as hard as my pull truck or race engine. If you ever lugged the motor for a period of time it would cause problems. Its just overrated synthetic with some purple dye in it and the dye is what causes problems I think.

If you don't believe there is any difference in oils buy some good oil and some off the shelf oil put some on your fingers and rub them together. You will feel the difference in film thickness.
 
The fact is royal purple is garbage oil I've seen more scored bearings and spun bearings when people use it. When it gets hot it turns to tar. Its not much of a problem in our cars cause the motors aren't working as hard as my pull truck or race engine. If you ever lugged the motor for a period of time it would cause problems. Its just overrated synthetic with some purple dye in it and the dye is what causes problems I think.

It's used in a lot of the trucks at work. The dye is broken down and dissolved in the first few hundred miles. If the Air Force goes out of their way to use it at the recommendation of the analysis dept (does analysis on all engine oil, including gasoline, diesel, and jet turbine engines), then I will definitely run it in my car.
 


It's used in a lot of the trucks at work. The dye is broken down and dissolved in the first few hundred miles. If the Air Force goes out of their way to use it at the recommendation of the analysis dept (does analysis on all engine oil, including gasoline, diesel, and jet turbine engines), then I will definitely run it in my car.

x2 thank you for this input.
 
It's used in a lot of the trucks at work. The dye is broken down and dissolved in the first few hundred miles. If the Air Force goes out of their way to use it at the recommendation of the analysis dept (does analysis on all engine oil, including gasoline, diesel, and jet turbine engines), then I will definitely run it in my car.

I'm so glad you're still here with us!
 
valvoline 10w-30 =) i have had too many rod knocks on cheap oil. i e house oil. people who know.... use valvoline. no synthetic here. its all a choice, as long as its full and maintained is the main thing. i have seen cars die off being constantly run low on oil. other things used in my oil changes(not every time, and never together) is seafoam, and lucas. =)
 
the oil cap says 10w-30, which is a little better since i think the L67 likes to have higher oil pressure. i always ran 10w-40 to keep my pressures up more and to make sure everything was lubed. started fine in the winter.

i did run 5w-30 for quite some time though.
 


I run Mobile 1 EP with the Mobil filter (blazer filter) and do my oil changes twice a year (spring, fall) and it cost $60 for the year. Theirs no reason not to run synthetic oil as its benefits out way the costs of a damaged engine. Synthetics oil has a much better ability to absorb water than regular where they typically stay seperated. This can and will help to protect you from spinning a bearing if you develope an internal coolant leak or after doing a set of LIM gaskets and you don't get all the coolant out. Some peoples time is worth more than the money so synthetics do have they're purpose.

I'll take amsoil over RP any day of the week. I run Mobile 1 EP because its about half the price of amsoil when on sale.
 


God, I hate these discussions on regular car forums, they are always so full of speculation, rumor, and outright misinformation. I'm trying to stay out of it, but I'll just chime in about 5W-30 vs 10W-30. They are both 30 weight oils, so what does it matter?!? The 5W will be thinner at very low temps, but that's it.

If anyone's actually interested in learning about engine oils, go to the forums on www.bobistheoilguy.com
 
Thanks guys for the posts, I have once again learned something new. I have always just taken my cars into a one stop shop and gotten the oil drained and whatever the cheapest oil is, it goes in. Keeping in mind I have never own a new car in my life. Now I am alittle more anal about this one.
Money really isnt an issue for me, especially when it comes to a $20 oil change or a $50 oil change, pennies are pennies, but if the warranty requires me to drain every 5000K, then putting a fully synthetic in would be pointless. When my warranty runs out next year and I have to choose from a oil the obvious choice would be synthetic, RP or Lucas. Higher cost of oil but lower than repairing an engine.
I want to thank BlueGTP, sabrewings, JJR for there input.
 
God, I hate these discussions on regular car forums, they are always so full of speculation, rumor, and outright misinformation. I'm trying to stay out of it, but I'll just chime in about 5W-30 vs 10W-30. They are both 30 weight oils, so what does it matter?!? The 5W will be thinner at very low temps, but that's it.

If anyone's actually interested in learning about engine oils, go to the forums on Welcome

a very VERY big x2. i actually frequent that website more then this one. i was gonna bring it up but just figured it'd be wasting my time. some people here seem to "stubborn" to learn new tricks

when looking at viscositys, the first number is the cold weight, and the second number is the weight at operating temps. when you start your car, your oil is either a 5 or 10w (or very close). obviously the 5 is thinner and will flow better NO MATTER WHAT. when your engine gets up to operating temperature, they're both 30 weights. so theres no difference. you could run 5w30 in your grand prix all its life and the only thing its gonna suffer from is better lubrication at start up
 
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