GC Syntec 0W30 6100km 02 Maxima VQ35

[apecush]

Here are the results of my latest (and first) UOA. This was the first oil change using GC, previously, an esso/exxon 5w30 was used in the engine. 6100km on the oil, 112,000 km on the engine.

The Blackstone tech indicated that I likely had a coolant leak due to the sodium content, however, this car has never used a drop of coolant, and never overheated. I think there may be an explanation to the sodium - it is either from the oil previously used (I understand that exxon/mobil/esso oils use sodium in the add pack), or from the container used to hold the oil before the blackstone kit arrived (plastic peanut butter container, washed thoroughly or so I thought)

If this was a coolant problem, wouldn't I see some potassium in the coolant?

As far as I can see, my wear metals are all ok, although the iron is a tad high. I'm doing a change this weekend and I'll do another analysis to see if those Na numbers come down a bit.

Anyone have any input on these results?


Al - 4
Cr - 2
Fe - 17
Cu - 3
Pb - 5
Sn - 0
Mo - 34
Ni - 0
Mn - 2
Ag - 0
Ti - 0
K - 3
B - 11
Si - 13
Na - 87
Ca - 1807
Mg - 415
P - 845
Zn - 977
Ba - 0

SUS@210F - 60.7
cST@100C - 10.42
Flashpoint - 370F
Fuel - Antifreeze 0.17
Water - 0
Insolubles - 0.4
TBN - 3.7

 

[Puppetmaster]

Interesting. FYI - I just posted my results and have pretty much the same car as you - I have high iron and lead.

Did you measure how much oil you drained? The VQ35s are known to burn oil, so I'm just curious to see what your oil consumption is like.

 

[edhackett]

Not all antifreeze formulations contain potassium. Sodium, 0.17 antifreeze, 0.4 insolubles and a TBN of only 3.7 at 6100 km all point pretty strongly to a leak.

Ed

 

[apecush]

Well, I'm doing another sampling today so I'll have to see what the new results are. I'm wondering how much of the old oil is left after draining when hot - the old oil used was apparently notorious for a sodium additive. Blackstone indicated that "if sodium is not an additive in the oil, then it shows antifreeze", so it seems like the 0.17% antifreeze is solely based upon the high sodium.

I didn't measure the quantity of oil that I drained.

 

[Al]

I would guess the sodium is from the Exxon oil. the '2' for chromium is a tad on the high side although it might not be much over '1' bc pf the analysis process.

 

[apecush]

On the recent change, I ended up draining about 3.5 quarts - this was with 1/2 quart added a few weeks before the change.

 

[apecush]

UOA #2 - Sampled one week ago. Again, 6100KM on the oil, which was run through the winter, so many starts from -30 or below. This test was done at fluidlife not blackstone like the initial test.

Again, sodium was flagged by the tester, but it is less than half of what it was before. Silicon is a tad high, and I have a good idea of what caused this (removal and re-install of air box).

Any additional comments?
Element - 118360 - 112297
Al - 0 - 4
Cr - 2 - 2
Fe - 19 - 17
Cu - 2 - 3
Pb - 5 - 5
Sn - 1 - 0
Mo - 10 - 34
Ni - 1 - 0
Mn - NT - 2
Ag - 0 - 0
Ti - 0 - 0
K - 2 - 3
B - 5 - 11
Si - 20 - 13
Na - 37 - 87
Ca - 1830 - 1807
Mg - 493 - 415
P - 906 - 845
Zn - 1050 - 977
Ba - 0 - 0
V - 0 - NT
cST@40C - 69.1 - NT
cST@100C - 11.64 - 10.42
Flashpoint - 370F - NT
Fuel - N - N
Glycol Water - N - N

 

[The Critic]

What oil did you use for the last two oil changes? Tell us the exact brand and model.

 

[apecush]

Both UOA's were performed on Castrol Syntec (german) 0W30 (fills 1 and 2 following the change to syntec). As I said in the first post, the oil previously used (before the Castrol 0W30) was a conventional Exxon/Mobil oil (previous owner had the oil changed at the dealership).