TBN Retention - Are We Missing the Point?

W. van Dam; D. H. Broderick; R. L. Freerks; V. R. Small; W. W. Willis

doi:10.4271/972950

1997-10-01

TBN Retention - Are We Missing the Point? 972950

Historically, the characterization of fresh and used diesel engine lubricants has been based on a limited number of analytical techniques. One of the most important analyses has always been the total base number (TBN) measurement. Although the TBN measurements are informative, easy, and quick, it can be misleading to base the judgment of an oil's performance solely on one criterion.

This paper offers observations from a field test, showing that some detergent approaches gave unacceptable performance even though the TBNs were at an acceptable level. It is hypothesized that some detergents do not effectively neutralize all acidic species present in the lubricant, thereby reserving their own base while in fact the oil may no longer provide sufficient protection against bearing corrosion. This hypothesis is supported with bench and engine test data. It is recommended that, at a minimum, total acid number (TAN) measurements be included in any analysis. Where time and cost allow, wear metals content, oxidation, soot content, and viscosity should also be evaluated.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Digital $37.00 Print $37.00

Preview Document

We also recommend:

Standards

SAE Mobilus®

Publications

News

Events

Professional Development

A World in Motion (PreK-12)

Participate with SAE

SAE Membership

Donate

TBN Retention - Are We Missing the Point? 972950

SAE MOBILUS