Should I request a TBN?

[Back40]

Getting ready to send off my first sample to Blackstone for a UOA on my 2005 Tacoma. Original OCIs were 3k but wanted to try 5k to see how the Castrol GTX 5w30 looks. The info from Blackstone suggest getting a TBN if your interested in extended OCI. Not sure if that means beyond my sample mileage or not. Should I get the TBN?

 

[04SpecV]

If its your first UOA on this engine, I'd just get a regular one. 5K isn't really an extended drain unless its all short trip driving.

 

[GROUCHO MARX]

I'd rather spend the dough on Terry's evaluation. As 'Spec said, you're not looking for a major interval extension, right?

 

[LargeCarMan]

Yes, go to 5K and do the analysis with the TBN. Then post it...Like I did a few of mine and see what the folks say. If its good for a few K more...go to 7.5 K and you know the oil will get there worry free.