UOI GC 8.0K 2YEARS cSt 100C = 14.2 ?

[fdcg27]

Wear metals look really high for only 8K and there is a significant amount of sodium.
This oil did thicken more than I would have expected in that mileage in this application.
After all, it meets BMW, Mercedes and VW specs for longer drain intervals in some much more powerful engines.
Early symptoms of leaking LIM gaskets?

 

[LeakySeals]

Thats a good point. Most of the Dex/LIM complaints from that era were the 3800 series II but its likely similar LIM materials were used.

 

[salv]

The 3.4 was the worst for intake manifold gasket failure. Many of them exhibit external leaks, but the wear numbers here are indicative of intermix.
The oil pan is going to need to come down to inspect the condition of the main bearings before spending money to replace intake manifold gaskets. If there is excessive wear, the proper course of action would be motor replacement.

 

[NMBurb02]

Originally Posted By: fdcg27
Early symptoms of leaking LIM gaskets?

If that is the case, shouldn't coolant have shown up on the UOA report?

 

[fdcg27]

Originally Posted By: NMBurb02
Originally Posted By: fdcg27
Early symptoms of leaking LIM gaskets?

If that is the case, shouldn't coolant have shown up on the UOA report?


Indirectly, it did.
The potassium, sodium and excessive wear metals came from somewhere.
I'm not sure how coolant is tested for, but it isn't that rare to see oil obviously contaminated with coolant show negative for coolant in a UOA report.

 

[cchase]

If there is coolant in the oil, it's not much and I doubt enough to create numbers like this.

On our 3.1, when the LIM gasket was bad, it was leaking so little the coolant level never changed and the K ppm in a UOA was into the triple digits if I remember correctly. So with K at 5ppm, this would be REALLY minor. Not enough to cause this much wear metal shedding in my opinion.

 

[tiger862]

I would never run oil over a year. Water from condensation will cause a jell and oil will thicken. Have seen motors have so much so that they locked up and would not even drain from plug. If no noises change regularly maybe every 6 months for a period of year of two then go once a year.

 

[JimPghPA]

I have been thinking about everyones comments regarding the levels of metal in this report:

Metals (ppm)

Iron (Fe) 110
Chromium (Cr) Lead (Pb) 196
Copper (Cu) 45
Tin (Sn) 7
Aluminum (Al) 21
Nickel (Ni) Silver (Ag) Titanium (Ti) Vanadium (V)
Contaminants (ppm)

Silicon (Si) 23
Sodium (Na) 67
Potassium (K) 5
Water (%) Coolant No

And one of the things that I was wondering is if I had done, or decide to do in the future, six month oil changes, and if each six month oil change show 1/4 the amount of metals that this report had, would those levels be considered high?

And is the depositing of metal into the oil related to time at all?

 

[JimPghPA]

BTW the intake gasket was done twice.

 

[JimPghPA]

The intake gaskets were done way before I started using GC.

 

[JimPghPA]

I did some google searches about how to read an oil analysis, and found something interesting regarding high iron.

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Table 3. Common Wear Situation Indicated by ICP
The hours of use on the oil strongly influences what can be considered normal. An engine with 100 ppm Fe at 250 hours is likely to be healthy. The same reading at 10 hours probably indicates a serious problem.

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The vast majority of this vehicles use (like 95 percent) was and is on a road with a 35 MPH speed limit, and often the traffic limits the speed to less the 35 MPH. Combine that with the quite a few red lights and the average speed is probably 30 MPH or less. 8025 miles divided by 30 MPH = 267.7 hours of run time. Right in the ball park for what this write up of how to look at a UOI is talking about.

 

[Brons2]

The oil is shot. You ran it too long. I bet TAN is high, but you didn't get TAN tested.