What is an AAR Rule 88 Rebuild?

Answer 1

According to the Association of American Railroads (AAR), when cars are 40 years old, built prior to 1974, they are no longer allowed for "Free Interchange" service. They may be handled between participating railroads on an exception basis or must go through a recertification program per AAR Rule 88 Rebuild or AAR Rule 88 Extended Service Status (reference the AAR Office Manual Rule 88 for the explanation of the requirements for the recertification programs). The recertification must be approved by the AAR Equipment Engineering Committee.

Cars built from July 1974 to present or cars which have received an AAR Rule 88 Rebuild or AAR Rule 88 Extended Service Status may continue in interchange service to 50 years of age. After these cars reach the 50 years of age they may be handled between participating railroads by agreement of all railroads concerned.