1.6 EB ,RL 5w20,18175 miles OCI,TAN>TBN

[ovidiu]

Here is my UOA from my Volvo V40T2 2014 with an 1.6 ecoboost engine. I drive a lot of highway. Sometimes i drive 60 MPH and sometimes 110 MPH.
The TAN is very high but the metals are still low. The oil is diesel like dark but as far I can see the engine is klean.
The Lab is a German-Lab the Oelcheck.
We have here in fact two UOA`s from the same oil at about 15k and 18k.The 5w20 is now a 5w30 oil.

The TAN = 6.25, TBN=3,43.

 

[ovidiu]

My question is ... could this oil despite the high TAN go even longer?.If the wear metals are looking good and the viscosity isn`t a problem...I mean how often do we see Blackstone UOA`s with TBN of 2 and the TAN could be whell above TBN but they don`t test it so nobody knows how high the TAN really is.
I have emailed David Granquist from Red Line and his opinion was that I could go while longer on this OCI, and that the oxidation is a false reading because of Red Line`s high ester content.
I will try to do a year OCI, this could become a 24/25k miles OCI.

 

[mattd]

I would have a hard time going a 25k mile OCI on a direct injection turbo engine. Though the wear metals are very low for the interval...

In order to know the true TAN you would have to have done a VOA to compare.

 

[ovidiu]

Here we have a VOA

https://www.oil-club.ru/forum/uploads/monthly_09_2013/post-2-0-88326400-1378458363.jpg

The TAN is 2.67

 

[mattd]

The oil definitely oxidized. The viscosity increased over 2 cSt @100C. I the TBN shows activive additive left but with TAN being almost twice the available TBN and a fair increase in viscosity I would change it and not push it longer than that. However still take into account what Dave at RL told you and ultimately it's your vehicle and money.