2003 Diamante, SHU 5W40, 6817m OCI

[Spetz]

Hi everyone,

I had a UOA done recently and not overly happy with the results.

I am not expert but it seems lead and iron are high,
Silicone is high (poor air filter?)
And fuel dilution is a minimum of 3% as that is the upper range the machine shows.

I am hoping that with the fuel dilution and silicone levels fixed then the metal wear particles will go down too?
TBN seems really good so potentially the OCI can be extended by a fair bit I would assume.
Molybdenum is lower than I'd hope, perhaps an additive like MoS2 would help?


Car: 2003 Mitsubishi Diamante
Engine: 6G74 3.5L V6
Miles on engine: 155,000
Miles on oil: 6,817
Oil: Shell Helix Ultra 5W40 (I am in Australia in case that makes a difference on the blend)
Driving type: Most is city driving with a few long trips but very few 1-2 mile trips (most about the 8-10 mile distance). It has about 600 miles of towing 3,500lbs too.


Code


Lead 42

Iron 13

Aluminum 3

Copper 6

Chromium 1

Tin 2

Nickel 0



Silicon 39

Sodium 4



Magnesium 13

Zinc 851

Molybdenum 41

Calcium 2117

Phosphorus 747

Boron 68



TBN 10.3

Soot 3

Glycol 0

Fuel Dilution 3% min

Oxidation 11

Nitration 0

Sulphation 14

TAN 0



f.debrus (mg fe/l) 5

Viscosity @100 C 13

Viscosity @40 C 92

 

[PimTac]

The towing is definitely a factor here in my opinion. Maybe a 10w or 15w would be a better oil choice?

What is the towing capacity on the Diamante?

 

[Spetz]

In kg, it's 1,500.
The car I tow is 1,000kg give or take a bit.
And the trailer I believe must be between 400-800kg.

I suspect I am right on the limit or may be exceeding the capacity by about 200-300lbs max.

Why would towing be such a factor, and a factor to what?
I think the main issue is the fuel dilution that may be causing poor readings.
Silicone is high but the air filter on it is a stock panel type but a fairly cheap one so I'll be buying better ones going forward.

 

[Bjornviken]

Just try a other oil. Have seen on ru-oil club that shu 5w-40 have high iron there too.

 

[Popsy]

+1 try another oil first. Inspect air intake too.
What oil filter are you using ? I've had success with Purflux filters in my Mitsubishi...but I don't know if you can find that in Australia.

 

[Spetz]

Is the low molybdenum an issue?

I still have 2 jugs of SHU 5W40, and also have a MoS2.
Maybe combining these would get the molybdenum up and wear down?

Also I am not sure if the wear particles are due to the fuel dilution or anything else?

As far as oil filter I used an AC Delco (standard).
The air filter is pretty cheap in it so I will buy a more expensive (better?) one too.

Still unsure what to do with the fuel dilution or how to check where it's coming from.

 

[zeng]

The TBN retention is very high, with a minimalist viscosity shearing.
Hence I would hesitate to accept there is fuel dilution albeit tested at 3 % by the lab, and it doesn't really matter for wear protection in this application.
I consider metal wear rates as quite good other than the high lead and silica , OCI probably could be further extended.

 

[Spetz]

Yes indeed it seems that if I could get fuel dilution under control and even used MoS2 as an additive I could get a lot more out of the oil.

 

[andyd]

I would go to 10w40 , 15w40 or 20w50 for 4 reasons. Ambient temp, miles, usage and fuel dilution. Total guess,How old are the O2 sensors, CTS, plugs wires?What do the plugs look like? . I would mix the 5w40 with a qt of 20w50. Shorten up on the OCI until you fix the richness

 

[Artem]

No way that TBN is correct, unless virgin oil will test like 20 or so on "their scale".

 

[zeng]

Originally Posted by Spetz
Yes indeed it seems that if I could get fuel dilution under control and even used MoS2 as an additive I could get a lot more out of the oil.

MoS2 may reduce duration of boundary/mixed lubrication regimes and friction coefficient in the vicinity of valve trains and piston ring/liner.

It may not help much in reducing the low'ish Fe ppm of 13 per 6k miles which I consider as normal.

High Si and lead here appears unrelated to boundary lubrication regime, IMHO.

 

[Spetz]

The O2 sensor is original... I do have a new one that I intend to install.

Plugs are about 45,000 miles old (NGK Iridiums) so should be fine I believe