7500 miles on oil and TBN of 7.1

[wcbcruzer]

Got my TBN results today from Blackstone Labs. 7500 miles on Mobil Delvac 15w-40 dino oil in the truck in my sig. 70% of those were city miles. Majority of time, engine reached full operating temp on each cold start.

TBN came back at 7.1! Comment from Blackstone:

"The TBN for this sample was 7.1. That is a strong reading and shows this oil still has lots of active additive left. 1.0 or less is considered too low."

I'm also running an Amsoil 2-micron bypass. I'm pleased to see this result and I'm also pleased with the quality of CJ-4 oil. Think again before changing your oil at 3,000-5,000 miles. I suggest doing an oil analysis at least once.

 

[Oldwolf]

Can you post a copy of your results?

I use Delvac Super 1300 too, but in a diesel Mercedes. I generally change the oil at 5000 miles.

 

[RWEST]

Don't get too excited about that TBN number. They're not absolutes - another lab, or even a re-check by Blackstone would probably show something different. How do the wear numbers look?

I had an instance in which they showed a higher TBN on a UOA than they did on a VOA from the same bottle...

 

[wcbcruzer]

Well that sucks. But even if the TBN has some error in it, I'm sure overall it still would show if your oil is good or not. Unless you're towards the bottom where the the error could be the difference between good oil or bad oil.

I would post my wear results but I don't have them. I blew it when I took the oil sample so I just got a TBN done. Will post next time.

 

[Steve S]

The oil is a long life oil. I wouldn't be surprised if the TBN is correct. Before EGR some over the road trucks were pushing 30,000 mile oil change intervals on the top HDEO oils . The HDEO oils are really heavy duty.

 

[TiredTrucker]

Originally Posted By: Steve S
The oil is a long life oil. I wouldn't be surprised if the TBN is correct. Before EGR some over the road trucks were pushing 30,000 mile oil change intervals on the top HDEO oils . The HDEO oils are really heavy duty.


And after EGR. The current oil change recommendation by Detroit Diesel for it's DD15 is 50,000 miles. I change my '06 Cummins ISX (with EGR) around 30K (no bypass filter). My '06 Jeep Liberty Diesel (EGR) gets changed at around 12K. My previous 1996 Cummins N-14 got OCI of 30K it's whole life and I gave it up at 1.4 million miles with only a couple of injectors and an accessory drive seal for any repair to engine. Been a fan of longer oil changes for quite some time. I do understand the paranoia of some to go long time though. Old habits die hard.

 

[RWEST]

Quote:
Well that sucks. But even if the TBN has some error in it, I'm sure overall it still would show if your oil is good or not. Unless you're towards the bottom where the the error could be the difference between good oil or bad oil.

For sure!! Like the other guys noted, that's a solid oil, and will certainly serve you well.

It's just that we sometimes take things as absolutes when they're not.

 

[bullwinkle]

It also helps that the CTD, in it's non-CR form, might be the easiest on oil of any diesel-the fact your running a bypass also helps-sounds like 10K OCIs would be a walk in the park, & 15K would be possible. Just goes to show some dino oils are as good as lesser hydrocracked synthetics.

 

[Steve S]

Originally Posted By: TiredTrucker
Originally Posted By: Steve S
The oil is a long life oil. I wouldn't be surprised if the TBN is correct. Before EGR some over the road trucks were pushing 30,000 mile oil change intervals on the top HDEO oils . The HDEO oils are really heavy duty.


And after EGR. The current oil change recommendation by Detroit Diesel for it's DD15 is 50,000 miles. I change my '06 Cummins ISX (with EGR) around 30K (no bypass filter). My '06 Jeep Liberty Diesel (EGR) gets changed at around 12K. My previous 1996 Cummins N-14 got OCI of 30K it's whole life and I gave it up at 1.4 million miles with only a couple of injectors and an accessory drive seal for any repair to engine. Been a fan of longer oil changes for quite some time. I do understand the paranoia of some to go long time though. Old habits die hard.
Even better more up to date information!!!

 

[wcbcruzer]

Hey guys, what about Zinc and Phosphorous? What is their role in motor oil?

Also, besides TBN and contamination, what else do I need to look at in order to know if my motor oil is still ok to use?

 

[Steve S]

Originally Posted By: wcbcruzer
Hey guys, what about Zinc and Phosphorous? What is their role in motor oil?

Also, besides TBN and contamination, what else do I need to look at in order to know if my motor oil is still ok to use?
The UOA!

 

[addyguy]

Post the darn UOA, and we can 'guide you through it'!

Free service here on BITOG!

 

[RWEST]

Quote:
Hey guys, what about Zinc and Phosphorous? What is their role in motor oil?

Anti-wear ingredients. Do a search on ZDDP (a compound of zinc and phosphorous) here or google it.

Please do post your UOA. There are people here who just wait for those things so they can review/comment..

That's a good thing!!

 

[FiremarshalRob]

Originally Posted By: TiredTrucker
Originally Posted By: Steve S
The oil is a long life oil. I wouldn't be surprised if the TBN is correct. Before EGR some over the road trucks were pushing 30,000 mile oil change intervals on the top HDEO oils . The HDEO oils are really heavy duty.


And after EGR. The current oil change recommendation by Detroit Diesel for it's DD15 is 50,000 miles. I change my '06 Cummins ISX (with EGR) around 30K (no bypass filter). My '06 Jeep Liberty Diesel (EGR) gets changed at around 12K. My previous 1996 Cummins N-14 got OCI of 30K it's whole life and I gave it up at 1.4 million miles with only a couple of injectors and an accessory drive seal for any repair to engine. Been a fan of longer oil changes for quite some time. I do understand the paranoia of some to go long time though. Old habits die hard.

WOW! 1.4 million miles. Those Cummins are beasts! We have the Cummins 300 in all our fire apparatus. What oil did you use in your N-14 if you don't mind me asking?