I’ve just spoken with both of the laboratories and they are very congenial. Micro Analysis Incorporated (www.microana.com) has two sulfur content analysis services:
Ion chromatography can determine sulfur content to 1,000 ppm (0.1%) and costs $30.
The Antek nitrogen-sulfur analyzer uses UV-fluorescence to determine sulfur content to 10 ppm (0.001%) and costs $70.
Huffman Laboratories (www.huffmanlabs.com) uses a combustion method with infrared detection to determine sulfur content to 100 ppm (0.01%). This costs $30 per sample with a two-sample minimum.
Choose your laboratory based on the accuracy (0.1%, 0.01% or 0.001%) that you need. I plan to submit oil or transmission fluid samples in the near future and will post the results.
Feel free to post your experiences with other laboratories that perform sulfur content analysis.
Try Wear Check Mobile Oil Analysis. I have two UOA's that show S results of 17,909 ppm for M1 75W-90 and 17,864 ppm for Redline Heavy Shockproof. They probably have the capability you need for your test.
Thanks for your replies and your excellent advice.
I've just ordered two oil sample kits from Wearcheck. The Wearcheck representative was very congenial over the telephone.
Although the $14 price of the MOB-1 kit is very reasonable, I decided to purchase the $24 MOB-2 kit for the additional information that it provides, including the total base number.
Wearcheck does provide a bargain by including sulfur content analysis in its basic testing service. Many of us have older vehicles and are interested in sulfur content as a rough indicator of the oil's compatibility with copper alloys.
I'll post the virgin oil analysis results when I receive them. Thanks again!