Does a TBN Test determine shearing?

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Sending off first sample to blackstone. Want to see how the oil held up to the shearing of the 6.0 powerstoke diesel. Do I need a TBN test for this?
 
Would you recommend getting a TBN report with my UOA even if I am not going to run extended oil change intervals. I don't tow anything real heavy (4000 lbs) but my trips are usually 10 to 15 min from house to job. Thoughts anybody?
 
Hi,
syndini - If you do NOT plan on extending your OCIs then a TBN test is really not REQUIRED

However, I would always go for extending your OCIs by using UOAs complete with both TBN and TAN tests
 
Originally Posted By: Doug Hillary
Hi,
syndini - If you do NOT plan on extending your OCIs then a TBN test is really not REQUIRED

However, I would always go for extending your OCIs by using UOAs complete with both TBN and TAN tests


Hi Doug using ONLY in this case TBN and TAN what numbers do you consider a condeming limit?

something like TBN drops below 1.0 and TAN rised above 1.0? or whatever.
bruce
 
Hi,
Bruce - I always used the TBN and TAN figures to "validate" each other really

My TBN minimum was always around 1 (D4739) some say 1/3 of new - I use 1!. (Average at OC 2.7)

My TAN limit is 7 (Average at OC 5.9)

Validating one against the other allows for errors in the Lab when combined with an engine's history and known top up

Many Lab variances are caused by them being unaware of the Oil Company's formulations and their "dynamic" changes - even Oil Company Labs too!

Best wishes for 2009 Bruce
 
Hi,
Bruce - I just did a quick check of some of my data and the TBN was typically around 1/3 of the TAN at OC (eg TBN 2, TAN 6) new TBN = 11

Typically on extended drains either of the Iron (150ppm) or Soot (3.5%) was the condemnation factor reached first
 
On a related subject... I spoke with a guy at Wearcheck, and he said that for gas engines they recommend getting TAN tested, but for diesel engines, they recommend TBN instead.

I guess getting both TAN and TBN would be best, but if you were only to get one, which one would you get for a gasoline engine? Most of the gas UOAs that I see here on BITOG have TBN, not TAN.
 
Hi,
QP - IME the TBN is all that is required in petrol engine UOAs unless you are going for extended OCIs over a long period in a low use vehicle

IMHO it is always productive to obtain both TBN and TAN in diesel UOAs if extended OCIs are being undertaken and high utilisation is involved. This is especially so if the vehicle is being driven and "managed" by other than the owner!
 
Originally Posted By: Doug Hillary
Hi,
QP - IME the TBN is all that is required in petrol engine UOAs unless you are going for extended OCIs over a long period in a low use vehicle

Well, my upcoming sample will have 5k miles and almost 1 year of use. Does that fall under "low use vehicle" classification?
 
Hi,
QP - You said;
"Well, my upcoming sample will have 5k miles and almost 1 year of use. Does that fall under "low use vehicle" classification?"

IMO that is a marginal call. If it were my vehicle I would be obtaining a TBN in order to decide whether to change to oil or not - if all the other aspects of the UOA were acceptable of course
 
Thanks Doug. This oil will get changed at that point, regardless of the results. The reason for this upcoming UOA is to monitor possible slight coolant seepage - my previous UOA showed a trace of glycol.
 
The change in viscosity on the report will show you how well it is combating shearing. It should be within their acceptable range.
 
Originally Posted By: syndini
Sending off first sample to blackstone. Want to see how the oil held up to the shearing of the 6.0 powerstoke diesel. Do I need a TBN test for this?


Blackstone will usually give the CST viscosity value under the properties section of the report. The first time you look at the number it can be confusing since most are used to seeing the SAE value of oil, i.e. 30 weight or 40 weight oil. If your UOA sample was from a 15W-40 oil, the CST viscosity at 100 deg C range should fall between 12.5 and 16.29 - if it is lower than 12.5 than the oil has sheared to a 30 weight.

Which brand of oil did you use?
 
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