Page 20 - WHITE BOOK

Acidity: In an effort to use acidity as an indicator three commercially available brake fluid samplesweretestedforacidity. Theacidnumbervaluesrangedfrom~0.20to~6.0(mg,KOH /gm). This showed there was such a wide variation in product make up it would make using acidity as a measurement of the used fluid’s quality impossible. The acid test was performed because in many fluid analysis protocols monitoring the acid number increase gives an indication of the amount of acidic constituents building up in the system, thereby warning of the formation of organic acids which indicate fluid degradation.
As stated, the reason the acid number cannot be used in the analysis of used brake fluid is new brake fluids vary in formulation and acid numbers (of the new fluids) range from low to very high dependingonthemakeupofthefluid’sadditivepackage. Inlaboratoryorfieldapplicationsone could never be sure of the original acid number, therefore using the acid number as an indictor of fluid quality on used samples is not possible.
Metals Analysis: The objective of the metals analysis was to determine if there were key indictors of degradation or contamination. The metals analysis showed there was no key indictor or combinations of indictors that would lead to a conclusion about the level the contamination or thefluidquality.
In our opinion, contrary to popular belief the level of copper in the bulk phase of the brake fluid did not demonstrate that the brake fluids had problems. This can be explained by all of the available literature that indicates copper is ubiquitous in the system, but in various sizes, molecular states, and morphology depending on the system variables. In fact, these data and literature (Reference A) suggests that as the antioxidants are depleted variations in copper content inthebulkfluidphasemaychange. Thisisduetothecopperchemicallyattachingtotheironin thesystem. Thismaydecreasethecopperavailableinthebulkphaseforanalysis.
In Graph #1 it can be seen that copper generally decreased (with a couple of exceptions) as mileage increased.
1200
1000
800
600
400
200
0
Copper vs. Mileage
Copper ppm
Thousands of Miles
Lab No.
GRAPH #1
Metals Analysis of Copper vs. Mileage - Data Sorted by Mileage y axis = 1,000 of Miles on System
101 Corporate Place Vallejo, CA 94590 800-645-5227 www.Herguth.com
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ppm or K/Miles
72 4681 A
72 4684 A
72 4687 A
72 4690 A
72 4693 A
72 4696 A
72 4699 A
72 4702 A