Most people use Blackstone..

I would say the Castrol you are running is just fine!

Check out http://www.bobistheoilguy.com/forums/ubbthreads.php for more in depth discussion (not just oil)

 

Holy wow, 150 people viewing the passenger car motor oil forum when I looked. Wow.

I should clarify that I will be using the Castrol at 197,000 miles, but reading the PDF from my previous post showing the results of Royal Purple, I may consider using that instead.

 

I dunno man, I wouldn't bother with Royal Purple. I think its an over-rated boutique oil personally.

A good quality top notch synthetic is always going to be Amsoil or Redline. (high price)

That being said, I use Pennzoil Platinum in my cars, because its excellent at its price point.

 

This is from the my350z.com forums, posted by Resolute.

Once things settle down for me, I'm definitely planning to send Blackstone my used Castrol High Mileage 5W-30 for analysis.

Unless someone has evidence to show how well Royal Purple performs in the VQ35DE, I'm just going to keep using the Castrol.

I cite my prior experience with the high mileage with my 1989 240SX when that oil was used I noticed a slight improvement in engine response. Might have been just me, but I wasn't expecting ANY performance gains.

 

I bought my maxima with 75 000 miles on it, and I’m sure the guy who had it before me didn’t use synthetic. So i decided i would start using synthetic because i always did on all my previous cars with no issues. My first oil change on the maxima I used M1 synthetic oil and after about 800 miles my check engine light came on with codes p0011 P0021. So obviously I didn't think it was an oil issue right away, so I broke my head searching for the problem. I had read somewhere that these codes could be related to low oil or dirty oil, but it didn't make any sense as I had just changed the oil. So I did 5 more oil changes with synthetic and after every oil change the damn codes would come back. Finally I decided to go back to regular oil just to see if it would solve the check engine light from coming on. Long story short I never had another check engine light since i changed back to regular oil, so basically not everyone could put synthetic. It all depends on previous oil changes, how dirty the engine is on the inside. Remember synthetic oil has cleaning agents, and sometimes putting synthetic oil will dislodge some sludge which will block other components.

Just my experience with synthetic.

 

Here's a link to the factory service manual, the ZIP password is
http://www.MegaShare.com/1879101

Looking in the EC.pdf, I see P0011 could be caused by accumulation of debris to the signal pick-up portion of the camshaft. Still worth looking at.

 

Holy annoying black text.

Sounds like a tall tale; not that it didn't occur, but that is highly unlikely.

 

Sorry about the black text.

I'm gonna try going back to syn on my next oil change, i'm also very curious if these codes will come back. And if they do it will confirm for me anyway that my car cannot use syn.

 

I've sent a couple samples off to Blackstone in the past and it helped me gauge what level of protectant is still left in the oil. It also analyzes metal levels that can sometimes be a sign of premature wear.

There's a lot of variables like driving style, environment and oil brand and type that play a factor in how often you should change it. The report you receive back from Blackstone is pretty comprehensive and it's interesting to read. Here's a sample:

http://www.blackstone-labs.com/report-explanation.php

 

Here's a better link:

http://www.blackstone-labs.com/gas-e...e-report-1.php

 

heres mine from my 5th gen


And from my mom's 4th gen

 

Synthetic is the way to go every 7.5-8.5K miles, Royal Purple seems to be rated much higher than mobil1

 

Synthetic oil is created from scratch, by chemical engineers. Conventional motor oil is refined oil with additives designed to make an OK lubricant. One example of the differences: in regular motor oil, you get paraffins. Ya, the stuff candles are made from. In synthetic, there are no paraffins. Thus, in the severe cold, regular oil looks like apple sauce, while synthetic is still a liquid. That makes a difference for getting the lubricant pumped on cold starts.

Another component of conventional oil is polymers for multi-weight. On wide spreads, like the old 10W40, conventional oil had a lot of this. 5W30 is rather wide too. There are two issues with the polymer additive in conventional oil. One is it isn't a lubricant. So the more of it you've got in the blend, the worse your lubrication properties are. This was a big enough component to cause manufacturers to stop recommending 10W40 for towing, and at least at the time that weight of oil disappeared off the market. The other issue is that with heat, time and chemical sheering, the polymer breaks down, and your oil turns more into a single weight oil. I forget which way it goes right now, but I think it tends toward the lower weight number with time.

Synthetic oils do not use this polymer additive to achieve multi-weight oils.

The short story is, synthetic is designed from the ground up to be a chemical engineer's ideal formula, while conventional is refined oil with more chemicals added to it to make it OK to work as an oil.

There are cases of cars where synthetic avoids engine damage. The Toyota Camry and Dodge Intrepid both had issues with narrow oil passage ways in the engine block becoming blocked with oil sludge. Owners using synthetic found they didn't experience the problem, as the burn point temperature for synthetic is so high (and again, no paraffins leaving deposits).

I've converted two older vehicles to synthetic, each with over 200,000 KM on them when I bought them. One was a Chev Lumina, and the other a Nissan Frontier. Neither had leaks. Both had smoother running engines (noticable at idle) after a couple of weeks
running on synthetic. In both cases, rust on the bodies killed these vehicles before anything went sour in the engine category.

I learned one more thing recently after talking with a Nascar engineer. The synthetic oil they use is zero weight. The engineer said it looked like pouring water. Apparently they have no interest in the longevity of the engine, only trying to get as close to zero friction as possible. So it is doubtful they learn much about synthetic properties for what you and I need on the car we want to run for many years - the racers pretty much destroy their engines every race, so they are looking for engine life of a few hours under extreme stresses.

Read this link for more info on oils:

http://www.calsci.com/motorcycleinfo/Oils1.html

 

The only problem is that oil companies now sell a group III basestock oil as synthetic. Group III basestocks are from dino oils and are highly refined....

 

Is there anything better (Castrol goes in ALL of my cars)

 

Sure, Redline, Shell Rotella T Syn, Amsoil.....

 

Yes, they have come up with a method which "dewaxes" the conventional oil by somehow destroying the paraffin molecules. That might avoid some of the bad properties of paraffin but it still has the approach of fixing a mediocre soup, rather than the approach of building a soup from scratch without the ingrediants they keep trying to mask and subdue. Fully synthetics are still made from the ground up, you just have to do some homework on what the labels mean. Mobil tried to stop Castrol from confusing the market with this cheap immitation and I read they lost that battle.

Put another way, conventional oil is like Aquafina's bottled water, which has one source of the Detriot river, then put through reverse osmosis. Synthetic is like the water of Pingualuit crater, which has no rivers flowing into it, and collects pure rain water and snow. Bottled water comes to mind because the marketing confusion is the same. Bottled water has imagery leading consumers to believe the water comes from natural springs or mountain rivers.

 

how many quarts of oil does a 2003 take?

 

For the 2002 its 4 and 1/4 quarts if you replace the oil filter when you drain the oil.