You purchase a kit , (here its about $12.00 to $15.00 ) that includes a bottle to put the sample in , and a shipping package .
Send it off , and in about a week they will E mail a result , and then send a paper copy of the results.
They will then keep track of each engine's results and compare the results each time you send in a test. They will alert you to a bad result or trend.
Go to a dealer for industrial or big truck engines and ask, for an oil sample kit.
Its OK to use DD lab kit for a Cat or Cummins or genset ,, its all the same laboritory tests.
The folks that built your engine will have the best technical info to call if a problem is found.
At resale time , the next owner will be impressed with many problem free years of test results , so you will get those dollars back.
-- Edited by FF at 04:45, 2008-10-09