Iron Levels in Transmission Fluid, Oil Analysis
 

Has anybody done any trending of iron levels to predict end-of-life of the CVT ?

I've just done one sample and at 866 ppm, it's about 12 times higher than the average level at a similar mileage-use for other transmission fluids, according to the database at Blackstone Labs (71 ppm, 19,600 miles). The fluid I had tested was in use for 20,300 miles, and dark-brown to black, and opaque. There was also sediment, like sand particles, that I could pull around with a magnet, so that iron is in addition to the 866 ppm. (I did ask my mechanic to sample midstream, but since his assistant did the change and I wasn't there to observe, I can't be sure that the sample wasn't taken at the beginning of the drain stream and all the wear-debris was from the beginning.)

I looked at an oil analysis guide from
http://www.syntheticwarehouse.com/br...uide_g2780.pdf
and using their chart for automatic transmissions as a ballpark guide, my sample would be in the Severity 4 category.

I have been disregarding the manual (which says change every 30K miles) and changing it every 14K, except this past 20K interval (had expensive state inspection emissions issues, so forgot to pay attention to the trans. fluid maintenance). With this recent fluid change, the judder, which only happened when accelerating abruptly from a stop on an uphill incline, was reduced like 90%. Will go in for another drain-and-fill in a couple of months, since I estimate only half of the used oil in the CVT got replaced.

This is a 2003 HCH, 78K miles on it, original CVT, have not done TSB 07-049 burnishing starter clutch (and hoping not to).

I'm more interested in the wear-rate, if anybody has any thoughts. Also, is it the flywheel teeth that erodes more than normal, and why (design-wise) ?