This Vehicle gets better and better. 40% Highway miles.
08 Subaru Forester-X. 9500 miles Subaru 5W-30
- Thread starter Al
- Start date
- Status
Originally Posted By: zach1900
No oil brand?
Subaru 5W-30 Synthetic Oil (Idemitsu)
Originally Posted By: Rand
Maybe use a couple quarts of thicker oil so it doesn't shear out of grade.
Why? Engines run fine on 7.5 cSt. Oil. Hard to knock the results.
No oil brand?
Subaru 5W-30 Synthetic Oil (Idemitsu)
Originally Posted By: Rand
Maybe use a couple quarts of thicker oil so it doesn't shear out of grade.
Why? Engines run fine on 7.5 cSt. Oil. Hard to knock the results.
Last edited:
There is no TBN, how can Blackstone can "feel free to go to 12,000"? Oxidation would be nice also.
Its comments like this that steer me to Polaris Labs.
Its comments like this that steer me to Polaris Labs.
Originally Posted By: Donald
There is no TBN, how can Blackstone can "feel free to go to 12,000"? Oxidation would be nice also.
Its comments like this that steer me to Polaris Labs.
I have yet to see a problem with low TBN. To me TBN is a waste of time. Thats just me.
Would you have a problem with the recommendation? I wouldn't. I am unlikely to go that distance but I would have no problem doing it.
There is no TBN, how can Blackstone can "feel free to go to 12,000"? Oxidation would be nice also.
Its comments like this that steer me to Polaris Labs.
I have yet to see a problem with low TBN. To me TBN is a waste of time. Thats just me.
Would you have a problem with the recommendation? I wouldn't. I am unlikely to go that distance but I would have no problem doing it.
I think TBN becomes important if you are considering going past 7500 and its your initial attempt in extending the OCI for this engine & oil combination.
Oxidation tells you the condition of the base oil and while viscosity also tells one the condition of the base oil, I think its best when they are both provided.
I buy a 10 pack of Polaris tests and its about $18.50 per test including TBN/TAN and oxidation & nitration.
Oxidation tells you the condition of the base oil and while viscosity also tells one the condition of the base oil, I think its best when they are both provided.
I buy a 10 pack of Polaris tests and its about $18.50 per test including TBN/TAN and oxidation & nitration.
Originally Posted By: Al
Why? Engines run fine on 7.5 cSt. Oil. Hard to knock the results.
Well obviously its opinion and comfort level.
Not all engines are flat-four with older design.
That engine would be perfectly happy on a 40/50wt oil.
It might not be happy if you push it hard with some 8cst oil. Somewhere in the middle would be best.
I would argue the the "results" being oil sheared out of grade is hardly optimal to extending.
I certainly wouldn't RECOMMEND extending it 33% with it already shearing that much(which was my point)
I was disagreeing with Blackstone's irrational comments rather than the "results" (wear metals) of the uoa.
Why? Engines run fine on 7.5 cSt. Oil. Hard to knock the results.
Well obviously its opinion and comfort level.
Not all engines are flat-four with older design.
That engine would be perfectly happy on a 40/50wt oil.
It might not be happy if you push it hard with some 8cst oil. Somewhere in the middle would be best.
I would argue the the "results" being oil sheared out of grade is hardly optimal to extending.
I certainly wouldn't RECOMMEND extending it 33% with it already shearing that much(which was my point)
I was disagreeing with Blackstone's irrational comments rather than the "results" (wear metals) of the uoa.
Remember Blackstone probably sees the TBN even though he didn't pay for it.
I don't think viscosity is an issue one bit, the viscosity decreased here but clearly the engine doesn't care one bit.
I don't think viscosity is an issue one bit, the viscosity decreased here but clearly the engine doesn't care one bit.
gathermewool
Site Donor 2023
Originally Posted By: 901Memphis
Remember Blackstone probably sees the TBN even though he didn't pay for it.
I don't think viscosity is an issue one bit, the viscosity decreased here but clearly the engine doesn't care one bit.
What makes you think that Blackstone checked TBN if it wasn't paid for?
This oil is known to shear down in very short order - it wasn't the mileage that did it, necessarily.
Remember Blackstone probably sees the TBN even though he didn't pay for it.
I don't think viscosity is an issue one bit, the viscosity decreased here but clearly the engine doesn't care one bit.
What makes you think that Blackstone checked TBN if it wasn't paid for?
This oil is known to shear down in very short order - it wasn't the mileage that did it, necessarily.
Originally Posted By: gathermewool
Originally Posted By: 901Memphis
Remember Blackstone probably sees the TBN even though he didn't pay for it.
I don't think viscosity is an issue one bit, the viscosity decreased here but clearly the engine doesn't care one bit.
What makes you think that Blackstone checked TBN if it wasn't paid for?
This oil is known to shear down in very short order - it wasn't the mileage that did it, necessarily.
They get the TBN anyway so they can make recommendations. If they're suggesting 12k is doable, likely the TBN is still fine. Those are good #'s coming off a PA winter.
Originally Posted By: 901Memphis
Remember Blackstone probably sees the TBN even though he didn't pay for it.
I don't think viscosity is an issue one bit, the viscosity decreased here but clearly the engine doesn't care one bit.
What makes you think that Blackstone checked TBN if it wasn't paid for?
This oil is known to shear down in very short order - it wasn't the mileage that did it, necessarily.
They get the TBN anyway so they can make recommendations. If they're suggesting 12k is doable, likely the TBN is still fine. Those are good #'s coming off a PA winter.
Originally Posted By: bigt61
If they're suggesting 12k is doable, likely the TBN is still fine.
Is that an assumption or do you know that for a fact?
If they're suggesting 12k is doable, likely the TBN is still fine.
Is that an assumption or do you know that for a fact?
Originally Posted By: Lubener
Getting an analysis w/o a TBN is like taking a bath without soap.
I suspect many people who have done dozens of UOA's and have seen wear metals remain low for 144K miles. Might disagree with you.
I have yet to see an abnormally low TBN on BITOG which led to excessive wear. Maybe you can correct me if I am wrong.
But obviouslyt YOU should get the TBN.
Thanks all for the comments. My plan is to do a 10K mile on the same oil. Steady as she gows. I might invest in a TBN just to prove its not necessary.
Getting an analysis w/o a TBN is like taking a bath without soap.
I suspect many people who have done dozens of UOA's and have seen wear metals remain low for 144K miles. Might disagree with you.
I have yet to see an abnormally low TBN on BITOG which led to excessive wear. Maybe you can correct me if I am wrong.
But obviouslyt YOU should get the TBN.
Thanks all for the comments. My plan is to do a 10K mile on the same oil. Steady as she gows. I might invest in a TBN just to prove its not necessary.
Last edited:
Agreed. Our heavy hitters here have established that TBN isn't the be all and end all in determining lubricant condemnation. It's darned nice to have, but lacking it is far from a huge deal.
Originally Posted By: Lubener
Getting an analysis w/o a TBN is like taking a bath without soap.
A good line
but I respectfully disagree.
I have posted several uoa's and always show TBN and TAN, but I have oodles of reports that don't have TBN/TAN. They still give me the vitals such as fuel, coolant intrusion, silicon intrusion and since they're for diesels I also get soot percentage. Believe or not, my "Mobil Delvac Accutrack" reports don't give TBN/TAN nor oxidation.
TBN and TAN are great for extending beyond a normal oci but if you have established a safe oci, those tests are not imperative.
I haven't posted my recent reports without TBN/TAN because they wouldn't be of any help to others, but I'm still getting a general health report and trend building.
I don't believe Blackstone automatically tests for TBN and withholds the info from those who choose not to pay for it. It seems like it must cost them extra to test for it (I'm making assumptions here).
The OP's reports don't indicate a low TBN nor a high TAN. There are no indications of excessive bearing corrosion, ring wear nor oxidation. Being a synthetic oil, 10K shouldn't be a concern regarding TBN. I would prefer something that didn't shear so much, but all seems well anyway.
Getting an analysis w/o a TBN is like taking a bath without soap.
A good line
I have posted several uoa's and always show TBN and TAN, but I have oodles of reports that don't have TBN/TAN. They still give me the vitals such as fuel, coolant intrusion, silicon intrusion and since they're for diesels I also get soot percentage. Believe or not, my "Mobil Delvac Accutrack" reports don't give TBN/TAN nor oxidation.
TBN and TAN are great for extending beyond a normal oci but if you have established a safe oci, those tests are not imperative.
I haven't posted my recent reports without TBN/TAN because they wouldn't be of any help to others, but I'm still getting a general health report and trend building.
I don't believe Blackstone automatically tests for TBN and withholds the info from those who choose not to pay for it. It seems like it must cost them extra to test for it (I'm making assumptions here).
The OP's reports don't indicate a low TBN nor a high TAN. There are no indications of excessive bearing corrosion, ring wear nor oxidation. Being a synthetic oil, 10K shouldn't be a concern regarding TBN. I would prefer something that didn't shear so much, but all seems well anyway.
- Status