For those interested, here's a copy of the post I did at BITOG, http://theoildrop.server101.com/ubb/...c;f=3;t=001413

Here's my 4th UOA on this engine. A little history:
- The first three were done using 5W30, the latest 10W30.
- The oil was not changed when the 2nd UOA was performed, just sampled and topped off.
- Current fill is M1 10W30 once more.
- My driving habits have changed somewhat as well, I did 90% highway when I did my first UOA and have gradually sfifted to less than 50% highwy today. And although I rarely rev to the redline (6500rpm), the engine sees 5000 rpm regularly.



1. As you can see, Blackstone is concerned about the lead wear. However I see a trend where the lead is going down; I'd like to be pleased with this, but I need reassurance from you "oildheads" that this trend is a positive indicator.
2. Iron still seems high to me, 2.5ppm per 1,000 miles. Although the iron wear is more favorable than the universal averages, I still think it's high.
3. All other wear metal levels seem to be excellent, even silicon has gone down some. If not for the iron and lead, I'd be a very happy camper.
4. I've read on other boards that this engine takes a long time to fully break in, so I plan on continuing UOAs to see if the levels of wear metals continue its downward trend.

Here's the discussion about the last UOA http://theoildrop.server101.com/cgi/...c;f=3;t=001063

Comments and feedback are both requested and welcomed! Thanks in advance.



<font color=red>chinee</font color=red>
03.5 G35s

 

Hey man thanks for posting your results. I have always wanted to get the oil checked on my personal cars but never seem to do it. Thanks for the "warning" on what to be looking for. Please keep posting as I am using M1 5W30 and changing every 4500-5000 and its good to see how long I generally can go.

03.5 Sedan/B.Sil/Prem/Wntr/Aero/Tint/Rims/Hotchkis Sways--WHRER ARE OUR PARTS!
69 Chevelle Hard Top BB/4.11's/Posi

 

IQ9,

I just got mine back and they recommended an interval of 6,000 miles. I use Mobile 1 synthetic 5w30 with stock filters.

Cost me $30 for the sample test.

 

chinee,
Thanks for posting this! I'm guessing that some of it has to do with the long break-in that is customary with these (and quite a few other) engines. From all of the oil analysis that I've read, and it's not a huge amount, the cars with over 40K miles or more can often go 10K or 20K without metal or particle problems. Keep in mind that this is with a good synthetic oil.
I'm a fan of Amsoil, which has come from quite a few comparisons that I've read over recent years. But I am not quite as detailed as many of the people on the oil forum that you show as a link.

 

Does anybody know what BRAND of oil our Gs come with from the factory?

2004 Sedan 6MT
Silver/Graphite/Premium/Aero
HuperOptik Ceramic 50
XM
Z-Tube/Stillen High Flow Airbox (OTW)

 

tinke... please post your UOA results, I'd like to see them for comparitive purposes. Also, unless you have a winter season where you live, it is preferable to use 10W30 like I do in Florida's year-round summer. The 5W30 is a thinner oil and flows better at sub-zero temperatures, while the thicker 10W30 provides slightly better protection.


<font color=red>chinee</font color=red>
03.5 G35s

 

It's in Pdf format. I'll scan it this weekend and post it.

 

Guys I am in bay area CA and am planning to use 5W30 synthetic blend most of the year with 4K intervals and between June-August time frame when it is the warmest use 10W-30 oil.

What you guys think?

So 4K seems to be break point where wear seems more for a synthetic blend?

2003 G35 Black Sedan

 

Is it okay to change from 5W30 to 10W30 frequently? Such as for the seasons?

Also, our manuals say that 5W30 is recommended... what's everyones opinion...

 

I would aloso like to know if I should switch to 10w30 from 5w30 mobile 1 synthetic for better protection. Is it likely to cost me any horsepower (prob. not)?

Gurgen

 

Okay, let's see...

Switching viscousities, from season to season poses no risks. Your engine benefits because it needs a thinner oil during winter to ensure flow, especially at start up. Try this, place a quart each of Mobil 1 5w30 and your local bargain oil outside on a very cold day or night. Once cold, uncap the bottles and see which oil flows and which one sticks like cold maple syrup. Which would you want in your engine?
During summer a thicker viscousity leaves more lubricant between the engine surfaces... more protection.

If I were going to change my oil every 4K, I'd certainly use a good conventional oil like GTX, Pennzoil or Chevron. Remember, the non-severe maintenance schedule for the G is 7500 miles on a conventional oil. Using synthetic for such a short interval is truly throwing your money away. I use synth to go 7.5K safely; although a couple of the wear metal levels seem high, they do appear to be trending down. If this trend continues, so will my use of M1 10W30, if not, it'll be time to try something new.

And switching oil viscousities probably affects horsepower less than changing gas octane grades. Your butt dyno will never know.



<font color=red>chinee</font color=red>
03.5 G35s

 

iafzal,

Not sure of the weather you experience, but in CA, I doubt you ever see temperatures fall below 0 degrees F [img]/w3timages/icons/smile.gif[/img]. I just checked the manual and both 10W30 and 10W40 are recommended for temps above zero. Maybe I'll try the 10W40 next time around.

<blockquote><font class="small">In reply to:</font><hr>

So 4K seems to be break point where wear seems more for a synthetic blend?

<hr></blockquote>

Not necessarily, I use the same oil in my wife's Sequioa and the labs recommend a 9,000 mile interval for this vehicle. It seems to depend mainly on your driving habits. I'm thinking of doing a UOA at 6500 miles and make a decision then.


<font color=red>chinee</font color=red>
03.5 G35s

 

So for CA, where the temperature at night hardly goes below 35 in the winter, do you recommend 10w30 or 10w40. THe latter would yield more protection once the engine heats up right? What do you think. I am due for an oil change. Also, if I am getting a TT setup, the oil temps are bound to be higher (10-20degrees celcius), do you recommend to never use 5w30 or 10w30/40? Thanks

Gurgen

 

Gurgen... very valid questions and although I wish I could provide you with the answers you seek, I'm just not knowledgeble enough to do so. I've read that turbocharged cars need extra protection, especially since the setups available for the Gs are not OEM. I would think that oil analysis would be invaluable if you chose to go FI.

Over on the BITOG thread, I just asked for a 10W40 recommendation, as well as a recommendation for an "ACEA A3/B4" rated oil. I've never really considered this option, but it's been mentioned over at BITOG, so I figure it best to find out a little more.

For those of you who are interested, the feedback on bob's has been interesting so far... go take a look; the link is at the top of this thread.


<font color=red>chinee</font color=red>
03.5 G35s

 

I personally recommend and use 10-30W here in CA. I have always used 10-30 all year long on all my cars.