Personally I like Pennzoil Platinum.
It protects as good or better than Mobil 1 and is cheaper to buy.

 

i like royal purple.its what i have been using for a few yrs now. it just seems to stay cleaner. i also change it around every 3k. i think that most oils are good as long as you keep them changed.

 

Royal Purple all the way.. but mobile 1 is great too!

I notice smoother idile with both, but at high rmp RP kicks but! Plus you will notice a drop in temp of about 10-20 degrees with RP

 

I put RP in my festiva and it has done great it even shut that noisy lifter up after nothing else would and gas mileage is slightly better so I am switching my v-8 dakota and my v-10 dually over the next oil change.

 

Sorry, but $7-8 a quart is outrageous for such a regular oil change. It barely adds any mileage to constitute spending the extra money. The only places I plan on putting RP in is my differential and maybe tranny.

 

A LITTLE MORE EXPENSIVE BUT WHEN YOUR REGULAR OIL IS GUMMY AND YOU HAVE BUILD UP IN YOUR ENGINE AND WHEN YOUR ENGINE SUDDENLY RUNS HOT AND THE REGULAR OIL GIVES UP THE GHOST AND YOUR ENGINE LOCKS DOWN YOU WILL WISHED YOU HAD SYNTHETIC BECAUSE IT WILL PROTECT THE ENGINE A LOT BETTER, i CALL IT CHEAP INSURANCE!

 

I have about 84,000 miles on my 2001. Do you think it'll be safe to switch to synthetic?

 

dummy zddp protects your cam

 

No need for the caps lock, but the Castrol my dad and I have used for ages has never failed and is cheaper than synthetic. The .2-.5 mpg you may gain from swapping to Synthetic motor oil does not save you any money in the long run when you change your oil at 3000mi and probably 5000mi intervals.

The only worthy synthetic oil applications would be your transmission and differential because it doesn't have to swapped at such a frequent interval and gives a MPG bonus therefore giving you gas savings that pay for itself.

 

With synthetic, you can stretch out the mileage intervals. I do mine every 5000-6000 miles since I went to synthetic. (Used to do it every 3000 on regular oil.)

I look at it from a scientific point of view. Neither oil will necessarily hurt your engine, but which flows better? An oil with molecules of various shapes and sizes, or an oil with molecules of consistent shape and size? Why do you think some older engines that "gunk" has clogged the leaks on start leaking after switching to synthetic? It flows better, less friction. Therefore, its better for the engine.

I think if you change your synthetic every 3000 miles you are wasting some money, but you have to do what makes you happy.

I believe it was Quaker State and Castrol, back in the days before my time, that used to use bees wax in their oils. If they will pull crap like that, why should you trust them with your engine? Enough said about that.

Royal Purple is the one synthetic oil, I believe, that has backed up their claims with independent test results. The rest, last time I checked, have not. Mobil1 has also been proven (although not in a lab, just personal testimonies) to usually be a good oil. Penzoil is just as good? Please.

However, all that being said, this argument is sort of like asking a group what is the best color for a pickup truck. You're going to get all sorts of responses, its a bit of personal preference.