For those of you interested, I got my oil analysis done with 7,565 miles on the oil, 14,928 miles on the G. The oil report seemed pretty non-descript with no alarming data to indicate a problem with this oil change interval, but I posted the results on the bob site to get feedback from the experts there. Take a look....

http://theoildrop.server101.com/ubb/...c;f=3;t=000739

<font color=red>chinee</font color=red>
2003.5 G35s

Chinee, Thanks for posting with your analysis results. They seem to tell an important story.
Who did your analysis for you and what did they charge?
Also can anyone post on that "bob site" for feedback?
Would be nice to get a comparo on other VQ's.
Thanks bro

<font color=red>GSM</font color=red> <font color=black>Silverstone Coupe</font color=black>

I haven't had much time lately to browse the usual boards but I picked up the links below from maxima.org. The first is a link to the fluid discussion board, the second to the oil analysis spreadsheet, with different oil brands and cars. I looked at the sreadsheet briefly and saw only one 3.5 VQ, and 02 Maxima. Will look a little more when I have time, but if anyone's interested, have fun!

http://forums.maxima.org/showthread....hreadid=100060

http://www.mindspring.com/~bill99gxe...%20Results.zip

<font color=red>chinee</font color=red>
2003.5 G35s

very interesting. I didn't know they had tests like this. I'm curious how my g35 coupe is doing.

I hope I didn't mess the engine up by putting in castro sythetic blend at 600miles, then Valvoline semi synthetic at 1400 and at 3k, 6k and now at 9k. So far the car has been good, but I think I might of put synthetic blend too early and didn't let the engine break in right.

BS G35C 6spd navi/aero/prem

Good googa mooga!

Hehe

chinee: You dodged the question.. where'd you get the analysis done?

2003.5 G35 Sedan Desert Platinum/Graphite Premium/Sport/Aero/Nav/Winter

Hi:

It was done at Blackstone Labs. Click on the link posted above to find more info.

Yuichi: When are you going to post the results of the stillen exhaust test results? If you attended the session, you should know how it went. Thanks in advance for the info on the dyno test.

Yuichi is waiting for that one website to publish the dyno shootout article. Then he will link us up. I think he is sworn in to secrecy [img]/w3timages/icons/smile.gif[/img]

<font color=green>-Rambo</font color=green>
G35c 6MT DG/Willow/HyperGround/BorlaExhaust

BlackStone Labs... here's their website http://www.blackstone-labs.com/free_test_kit.html . They can send you the sample kit free and it's $20 when you send your sample in.

Here's a link where a there an extended synthetic oil life study; they've got Mobil1 up to 15K miles and the oil is still good. http://neptune.spacebears.com/cars/s.../oil-life.html

Good reading if you're interested in that sort of thing.

<font color=red>chinee</font color=red>
2003.5 G35s

Hi, chinee. I printed your oil analysis and gave it to one of the Chevron Lubricants folks who rides in my vanpool. He had these comments.
- The results are typical for motor oils at that mileage.
- He is also concerned with the high lead and iron content.
- The high calcium content is due to relatively large amounts of calcium sulfonate used to neutralize acids. This is indicative of a motor oil blended for large change intervals. And, as someone in this thread mentioned, it replaces ZDDP. BTW, the calcium content should remain the same over the useage life of the oil.
- You would get the same results with a high quality non-synthetic motor oil.

<font color=blue>Dan</font color=blue>

Thanks Dan, but from my reading on bob's board, I suspect that a non-synth oil may lose some of it's viscousity, and ability to lubricate (and protect), way before my 7,500 mile interval, hence my usage of a fully synthetic oil. Ask your buddy if a non-synth would have exhibited more wear (yikes!) at the interval I used, I'd like to hear his take on it.

<font color=red>chinee</font color=red>
2003.5 G35s

Hi, chinee. I was able to talk to one of the motor oil specialists at work and review your oil analysis with him. He races cars, and consults with manufacturers and NASCAR and Indy car teams on lubrication issues. In his opinion the iron and lead levels, as well as the other wear metals, are nominal and are nothing to worry about. Your analysis is confusing in that the oil use interval is 7,565 miles but the report says that the universal average numbers are for 3,800 miles. Would the universal average numbers be twice as great at 7,565 miles?

Another concern is the method of sampling. The lead universal average is stated to be 6 ppm. Brand new unused oil can show 3-4ppm lead depending on the detectable limit of the analysis method. Also, was the test equipment thoroughly cleaned between samples?

Would a non-synth have exhibited more wear? The specialist responded that engine wear should be nominal if you follow the engine manufacturer's recommendations for oil grade and change interval. This is a conservative answer but it speaks volumes.

FWIW, ChevronTexaco, and probably other major formulators, test their conventional motor oils in taxi fleets, a very severe duty cycle, at change intervals of 7,500 and 10,000 miles. The engines show nominal wear even at 100,000 miles.

<font color=blue>Dan</font color=blue>

"Your analysis is confusing in that the oil use interval is 7,565 miles but the report says that the universal average numbers are for 3,800 miles. Would the universal average numbers be twice as great at 7,565 miles? "

I was confused at first as well. The universal average numbers reflect the average results for all analyses done for this engine type. The average oil drain interval (ODI) is 3800 miles, exhibiting average results as indicated for each category. So my actual results should reflect double the universal (or close)...that is if all things were equal.

I can't speak for the test equipment at the lab, but I installed a fumoto valve in place of the oil plug, pictured below.

This allows for oil changes with less spilt oil, I also wipe any debris off the valve and let the oil drain for about 10-15 seconds before getting my sample, to reduce the chances of contamination.

Unfortunately, at both Bob's site and at maxima.org, I can't find but one or two other used oil analyses for the 3.5VQ. So I'm pretty much alone in this endeavour.

And for anyone wondering why I'd go with synth oil and a 7500 ODI, it's because both my spouse and I drive 30Kmiles/year each, that's 16 oil changes a year with a 3750 mile ODI, essentially every 3 weeks I'd be under a car changing oil. With synth, I only need to perform 8 oil changes per year!

<font color=red>chinee</font color=red>
2003.5 G35s

It is confusing. In other words, you would divide your engine's wear numbers by approximately one-half to relate them directly to the universal averages?

As an example. Lead would be 11, 6 not 21, 6.

<font color=blue>Dan</font color=blue>

Correct dspisak... if my wear is too be considered normal for this engine type, my lead level should be closer to 11 and not at the indicated 21ppm.

One poster on bob's stated that the lead may be from an engine that is still new and breaking in. And I've heard (maxima.org) that Nissan engines take relatively long to break in. So I'm hoping the lead level will be lower on my next sampling.

<font color=red>chinee</font color=red>
2003.5 G35s