undecided.steve

+1
I pretty much agree with you bullitt15 !
Amsoil invented synthetic oil so it goes to reason they would be good at what they do.
There is a lot of debate these days over Mobil 1 going Group III instead of Group IV (true full synthetic) but nothing has really been proved one way or the other.
I agree concerning RP I feel it's overpriced.

I do differ with you on Penzoil though, but ONLY the new Platinum Synthetic which is getting good reviews over on Bobs the Oil Guy site.
I would not use the Penzoil dino oil though because I've heard, I don't know, but have heard it waxes up.

Castrol Syntec is another good oil that meets Porsche, VW, Audi specs which are pretty stringent.
I use that in my daugter's 2003 Jetta and it seems good at 80k miles.

My take on the entire oil debate is that if you change at 3k or so and that 3k is not total sitting in NYC stop and go traffic, just about any of the oils are fine.
Spend the money on a quality filter.
Anyone who believes this 10k+ mile oil changes is an idiot imho and even if you change the filter, why not just dump the oil at the same time?
You're under there anyway...

All that being said, and to totally contradict everything I have written, my 92 Caprice is approaching 1/2 a million miles on the original motor and tranny.
Nothing but Castrol GTX dino changed at 4-5k and whatever oil filter was on sale, including Fram (I know they suck).
Then there is my 2000 Dodge Caravan approaching 145k miles, same story.
My 87 T-bird went 200k before I sold it.
My 1988 Eagle Premier (Volvo 760 V6 motor) went 350k before I sold it.
...and so forth....
The secret is more in the changing of the oil religiously, along with a little luck and not abusing the motor.

98 Mustang GT

I read the owners manuel in my 98 and it says 6 quarts, also I will stick with synthetic in my motor. I buy the mobil 1 synthetic oil at wal-mart (5 quart) for $20 then get the oil filter +1 quart of oil at the parts store.

undecided.steve

There you go!
Some Stangs need 5 quarts and some need 6 because they changed oil pan designs.
Check the owners manual and double check with the dipstick on a cold motor with the car on mostly level ground.
Mobil 1, Wix, Motorcraft, K&N, Purolator etc are all quality filters.
Avoid Fram unless you are buying the top tier ones which are *decent* although much better filters can be bought for less money.
IMHO synthetic is the only way to go in high performance, ragged on cars.

golferjoe11

I just turned 40k miles on my 04' GT, and did my first synthetic oil change with Moble 1 and motorcraft filter. The ownersmanual said 6 quartes, and 6 quartes did the job. Im pretty impressed with the mobil 1 oil, the engine feels a lot smother and also sounds smoother (no more, tick tick tick noise from the top end). I have a question though. How often does synth need to be changed? Can I stretch it out to 7k miles or is 5k the limit?