Hi guys, This is my first post so apologies if there are errors.
After my first oil change by Subaru I suspected that the oil used was not as specified by the manual which states use 5w-30 but NEVER to use 0w-20 which I suspected they used. My analysis was done by ALS Tribology here in Australia. The report states that viscosity was low due to fuel dilution. I suspect it was low because they used 0w20. Here are the results...
COMPONENT Kms 16900
MACHINE Kms 16900
OIL Kms 4400
OIL MAKE Unidentified
OIL TYPE SAE
OIL GRADE SAE 5W30???
Physical Tests
Water (%) span>
Viscosity (cSt,100°C) 8.3
Fuel (% by G.C.) 1.2
Dispersancy Pass
Oxidation (Abs) 13.5
Nitration (Abs) 8.4
Total Base Number (FTIR) 8.3
Now my questions to you all is:
1) Would a 1.2% fuel dilution cause a shearing of viscosity to 8.3 if 5w30 oil had originally been used? (My basic understanding is that if that oil had been used minimum value should be 9.3 and max 12.49 @100deg C.)
2) Is a 1.2% fuel dilution after 4400kms (2500Mi) and acceptable value for a direct injection, turbo, high compression engine (10.6:1) such as the FA20DIT?
3) Are these totally acceptable values, the correct oil was used and I am overreacting?
Any input appreciated. If you require anymore information please let me know and I will provide it to you.
Thanks all.
After my first oil change by Subaru I suspected that the oil used was not as specified by the manual which states use 5w-30 but NEVER to use 0w-20 which I suspected they used. My analysis was done by ALS Tribology here in Australia. The report states that viscosity was low due to fuel dilution. I suspect it was low because they used 0w20. Here are the results...
COMPONENT Kms 16900
MACHINE Kms 16900
OIL Kms 4400
OIL MAKE Unidentified
OIL TYPE SAE
OIL GRADE SAE 5W30???
Physical Tests
Water (%) span>
Viscosity (cSt,100°C) 8.3
Fuel (% by G.C.) 1.2
Dispersancy Pass
Oxidation (Abs) 13.5
Nitration (Abs) 8.4
Total Base Number (FTIR) 8.3
Now my questions to you all is:
1) Would a 1.2% fuel dilution cause a shearing of viscosity to 8.3 if 5w30 oil had originally been used? (My basic understanding is that if that oil had been used minimum value should be 9.3 and max 12.49 @100deg C.)
2) Is a 1.2% fuel dilution after 4400kms (2500Mi) and acceptable value for a direct injection, turbo, high compression engine (10.6:1) such as the FA20DIT?
3) Are these totally acceptable values, the correct oil was used and I am overreacting?
Any input appreciated. If you require anymore information please let me know and I will provide it to you.
Thanks all.
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