Used Oil Trend Analysis Recommendations

Messages
308
Location
SF/Bay Area, CA
I've reviewed a lot of individual oil analyses on this site but haven't seen much (any, actually, yet) info on how to trend the analyses and what are the important line items to be watching. Also, I've seen no info on warning limits. Here is a nice set of data: Maxima Oil Analysis Spreadsheet Updated 12/09 My question is, now that one has this info, what are they to do with it? Thanks for listening!
 
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3,845
redlines, Thats because trending and interpeting data is a science and an art. I spent 24 years figuring that out. How much time do you have to learn ? It is a time consuming job, and not accurate unless you have a clue. I do not mean this to demean anyone or sound like a arrogant butthead, as you don't need to be a brainiac to do this but it is a strange combo of mechanics,science and interpretive skills. I also don't post everything I tell my customers about the trends, various choices of products and what and why of the values. I do usually spend at least 30 minutes evaluating a test a result then put that in a written format with the results for our customers, many times using the phone to alert them to a problem or issue that needs immediate attention. [ December 13, 2002, 01:39 PM: Message edited by: Terry ]
 

MolaKule

Staff member
Messages
21,698
Location
Iowegia - USA
Redlines, Keep tuned, there is a wealth in information in those analyses. Sone of the items I look for is engine type, oil used, drving conditions, top-off oil used, wear rates in various engine components, etc. I may want to compare my oil analysis with another's who is using the same oil and look for trends in Total Base Number, for example, to determine if the oil holds its acid-fighting capabilities well and if it would really go for an extended drain interval. In the virgin oil analysis, one can see the levels of basic additive components before the oil is corrupted by wet weather, combustion temps, etc.
 
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5,785
Location
Dixie
68Redlines73, The main things I look for in an oil analysis are: 1) abnormal contamination, especially from coolant and silicon 2) normal wear rates - you need to look carefully at the # of miles on the sample 3) viscosity within +/- 15% of the baseline value 4) A TBN of at least 4.0 to insure the engine is staying clean 5) If you have baseline data on the formulation, you can also look at additive levels, but those are somewhat insensitive to oil degradation and can be misleading .... Each engine has a unique wear pattern and absolute wear rates are heavily influenced by driving conditions. So it's isn't really possible to compare vehicle A to vehicle B in terms of wear rates, even if they have the same engine. There is a fair amount of test to test variability in oil analysis results, so you really have to test the same engine at least three times to get a feel for how well it's doing.
 
Messages
3,693
Location
Chattanooga, TN
quote:
Originally posted by TooSlick: 68Redlines73, The main things I look for in an oil analysis are: 1) abnormal contamination, especially from coolant and silicon 2) normal wear rates - you need to look carefully at the # of miles on the sample 3) viscosity within +/- 15% of the baseline value 4) A TBN of at least 4.0 to insure the engine is staying clean 5) If you have baseline data on the formulation, you can also look at additive levels, but those are somewhat insensitive to oil degradation and can be misleading .... Each engine has a unique wear pattern and absolute wear rates are heavily influenced by driving conditions. So it's isn't really possible to compare vehicle A to vehicle B in terms of wear rates, even if they have the same engine. There is a fair amount of test to test variability in oil analysis results, so you really have to test the same engine at least three times to get a feel for how well it's doing.
Excellent summary. We see too many analysis of single smaples and one time only samples on this board. It woudl be great if we could post three samples from each engine as you noted. Your last two paragraphs are so true, NO TWO ENGINES WILL PRODUCE THE SAME RESULTS even if the same oil and same conditions applied yet it seems that this is exactly what we are trying to do, get all smaples to fit into a common mold.
 

Patman

Staff member
Messages
21,989
Location
Oakville, Ontario
Spector, you raise a good point, which is why when I post my analysis results for my vehicles, I will include previous results and info to compare (if there were previous results) It helps to show if any changes that I made show any difference from one to the other, instead of just seeing the raw numbers on their own.
 
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