UOA @12k miles, synthetc vs. regular oil
 

My Z is now at ~12k miles. Until about 5,500 miles I would just go to the dealership for the standard oil changes at 3k miles or less.

I was curious to see the difference between using synthetic & regular oil. Although I think the results are somewhat skewed because of the engine still breaking in. Either way I'm pleased with the oil/filter combo, it's keeping my motor healthy. I used the same combo again with the last oil change, but I might try something else off the shelf next time. Maybe Pennzoil Platinum and K&N filter or PP w/ a Purolator filter.

1st UOA
10/2009
regular oil & OEM oil filter at the dealership
~3k miles & ~3 months of use (NJ)
80% city / 20% highway

2nd UOA
3/2010
Castrol Syntec 5w-30
K&N oil filter
~3k miles & ~6 months of use (NJ)
25% city / 75% highway

3rd UOA
5/2010
Castrol Syntec 5w-30
K&N oil filter
~3k miles & ~2 months of use (FL)
25% city / 75% highway
Note: replaced air filters with OEM at about 13,800 miles.

4th UOA
7/2010
Castrol Syntec 0w-30 aka "German Castrol"
4200 miles & months of use
25% city / 75% highway
~30 passes at the 1/4 drag strip

http://i198.photobucket.com/albums/a...70z/D90482.png

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http://i198.photobucket.com/albums/a...70z/E11950.png

http://i198.photobucket.com/albums/a...g?t=1279845517

so what your saying is buy redline oil right?

Sure, if you want to spend the extra money. Redline 5w-30 is $10/ qt versus the $22 I paid for the 5+ qts of Castrol Syntec 5w-30.

That and I just prefer to use off-the-shelf fluids for something changed as often as engine oil. But for diff & trans (something not as often), I use brands like AMSOIL, Motul, Redline, etc.

thats why my friend we have amazon

Yes but it still comes out to a bit more than $10/qt even if you buy in bulk from amazon. More than I want to spend for motor oil, 370Z or not. I will try other off the shelf "normal" synthetics and have them tested but I don't feel the need to spend that much on motor oil.

Give German Castrol a try. 0w-30 European Formula. Can be found at your local Autozone and sometimes Pep Boys.

Good stuff!! yeah, oil is completely personal preference. I myself use redline but that's only because it helps me sleep at night. No evidence stating one oil is better than another. Thanks for the useful info +rep!

your regular oil was the nissan ester, correct? the changes look excellent!

It was not Nissan ester oil, just the regular stuff.

how much do the tests cost?

i think it's $22.50 from blackstone...

FYI: Pureone by Purolator's your best bet, oil filter-wise, according to an engineer who tested them ALL on the market. I'm just passing on the info', man.

so that can be added to his oil change price here and there so he is still paying a little extra for his changes if he keeps getting tests done.

It's another $10 for the TBN test, I wanted to see how the oil would be after 6 months & 3k miles. And I don't mind paying for the testing, I get some good info out of it. More than likely I'll keep testing my oil, I'm a bit of a nerd.

I have less than 500 miles on my Z, when should I make the first Oil Change, and what oil do you prefer...... I have always used Mobil 1 Syn... also does the syn effect the oil temp. issues ?

This is my second Z car that I have bought new. Both times I had the oil changed at ~1200 miles. I went with just the regular oil at the dealership for the first few oil changes. That's all just a personal preference.

The synthetic oil seems to make a difference when running the engine hard. Example: a quick run on the highway through 3rd & 4th gear the oil temp would spike up 10 to 20 degrees (from what I remember) with the regular oil. This wouldn't happen so much with the synthetic oil, definitely more stable oil temps. From what I noticed it takes more prolonged runs to get the oil temp to rise significantly.

Anyone here knows if there's a MOBIL 1 formula with the ester thingy? I'm kinda faithful to that brand, but all the ester hype is getting to me--I guess. BESIDES, I can get MOBIL 1 oil at about $4.99/qt.; b-i-g difference from those outrageous prices for Redline, Nissan's ester one, etc.

RL and some others have esters but do they have the mysterious nano-particles? That is the question :ugh2: Personally, if the oil is API SM certified, you're good to go but synthetic does have advantages over dino.

No, no, I always use synth', IDZRVIT, but I was wondering if MOBIL 1 has a formula which contains the ester deal.

thanks for posting the info, great stuff here to make good oil decisions +1

Here's what Mobil says about its oil containing esters - usually. Well Mobil, does it or doesn't it?

Ester Oil and Nissan Engines

Oh, and it has been used in their synthetics.

http://www.mobiloil.com/USA-English/...Ester_Oil.aspx

Good UOA's. Any reason for changing out the oil before the recomended oil change interval (OCI) at 3750 mi (yours was at 3K mi)? Lower OCI will normally give better numbers, but I do not think 750 mi would have made a big difference. The silicon has improved but still on the high side (dirt in the air filter) you may want to keep on an eye on the air filter and clean it on a more frequent basis or replace it with a better paper filter.

I have to say this is a very good UOA with only the viscosity breaking down early. Keep paying the extra $10 for the TBN test, its worth every penny. :tup: I wish my UOA's were this good.

Why change at 3k miles instead of 3750? Force of habit I guess. And I typically don't do much driving during winter time, so it ends up taking me a while to reach 3k miles. I'm no oil specialist but my guess is that the frequent short trips over the past 6 months might have had some effect on the slight viscosity breakdown.

Update: I'm already up to 1500mi since the last oil change. A few more weeks and I'll have another report on the Castrol Syntec 5w-30.

My Z is up to 12k miles and 1 year of ownership and I'm still running the original factory air filters. It probably wouldn't hurt to change them out now. Thanks for the tip.

Sry for the long delay in response. I have been offline all week, busy at work.


Try trips of 7 miles round trip per day to and from work, now that has a tendency to consume oil because the condensation that builds up in oil with short trips and not enough driving to heat up the oil to burn off the condensation. I am no expert either on oil, but I think the break down of the oils viscosity is due to the shearing of the oil from our high tolerance engines.

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Here is a snippet from Resolute thread on my350z:

"What do the viscosity numbers mean, and how do I read them?
The viscosity numbers are from a specific test to determine the viscosity of an oil at a given temperature, as measured in cSt (centistokes). A higher number means a thicker oil at operating temperature, and a lower number means a thinner oil at operating temperature. A higher or lower number is neither good or bad in and of itself, it is merely a measure of the oil’s viscosity. Some oils thinned out, or sheared, from use and became thinner than their original grade. For example, a used 30wt oil might have viscosity numbers which correlate with a 20wt oil, indicating it is prone to shearing in the VQ."

VQ Oil Analysis and Info - MY350Z.COM Forums

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I used to run PP in my Z33 and it resulted well with short OCI's and DD driving with no track or auto X. I ran it for one OCI with the Z34 and it held up ok but not a good test as the engine was still sealing and seating and a lot assembly lubes still needed to be cleaned out. But what worked well in the VQDE engines will not necessarily net the same results in our engines. Your best friend is a used oil analysis.

I would like to see an oil guru step up to the plate and open a thread similar to Resolute's thread on my350z on oil and UOA’s and the collection of data to inform which oil for the type of driving is best for our engine.

May want to look into Amsoil's Nano Paper Air filter as a stock air filter replacement.

Now that spring is here I bet we will see a lot more miles start to rack up on the odometer and hopefully more UOA's posted. Look forward to your next UOA. :tup:

Before I moved here, I used to drive a 8 mile round trip. Sometimes during the the winter [in NJ] the oil temp would barely start moving until I almost at my office. Now I'm up to a 45 mile round trip, plenty of time to get the engine warmed up.

I looked into the Amsoil air filters, it seems they don't have one for our cars yet. I think I will go with Purolater oil & air filters next time around.

are the factory oil filters the best to use ? I was thinking about going with K/N filter and Castrol Edge. Anyone have any suggestions ?

Purolator oil filter (the shorty) is what I am currently runing. Will switch to the extended one on next change. Have not heard anything on their air filter. Gotta be better than the stock one though. My stock filters were dirty and needed replacing after 10k miles. I am running Amsoil Ea air filters now, then again its with Injen's CAI.

My #1 choice would be Purolator Pure One and this came from my tribologist (dysonanalysis).

# 2 K&N

Stay away for the time being, Amsoil's oil filter. They are not a recomended on Amsoil website as an oil filter for our Z34.

Dunno know much about Castrol Edge.

Your statement is confusing. Amsoil sells a Wix filter for the Z34. Are you saying Amsoil doesn't recommend this filter but is selling it anyway?

I think what means is that Amsoil doesn't have a specific model [AMSOIL branded] oil filter that would fit the Z34. Instead they just recommend a WIX filter.

I was referring to the Amsoil EA012 oil filter. It's their best oil filter for the 350Z but I found out by trial and error that it is NOT for the 370Z. Even though it fits and is cross referenced to the G37 it is NOT for our 370Z.

The Wix is NOT of the same quality of the EAO12, therefore I would recommend Purolator PureOne PL14612 or the extended filter PL14610.

If you can not get the Purolator then my second choice would be K&N

Hope this clarifies.

Cheers
Curtis


Correct

bump!

I got more test results in today (refer to the original post).

seems you had the good fortune of getting a good engine... nice one...

bump for more results.

I tried a new oil this time: Castrol Syntec 0w-30 aka "German Castrol". I wanted to use a thicker oil because of the summer heat down here. I also started going to the track once a month as well, better protection for the engine is a must.

old thread I know, but isn't 0w-30 even thinner than 5w-30? The first number is the oil's viscosity when the oil is cold and the second number is its viscosity when hot. Therefore, a higher number equals a thicker flowing oil. So I think you'd be better off running 10w-30 for hotter climates.

Side note, does anyone know what exactly the 5 or 30 number refers to? I don't think the units are cSt. Just a relative number to other oil viscosities at certain temps?

Been running AMSOIL and Wix filters for years. Great combo.

It's thicker than the other 5W-30's I ran previously. I think I might finally try redline engine oil next, just to see there's any noticeable difference.

And FWIW, the car sat for 3+ weeks and started right up, no funny noises at all. My engine seems to like it over the oils I've tried.

yep, amsoil SS0 0w30 here too... used in my last 3 cars. It cooled my oil temps down in my Z by about 10-15 degrees. Now that it's cooled down I have yet to go over 200 degrees under normal driving conditions and even getting on it a few times. My typical temp is 180-190.