Tony:

If the cars are over 40 years old they cannot be interchanged between roads, AAR has an extension on the cars under AAR rule 88, The FRA rule is 50 years. The AAR Interchange Rules set the 40 year life and later the 50 year life. 50 years is also the limit under FRA Regulations. To operate past 50 years requires a waiver from the FRA. The AAR created the Increased Life Status provision under Office Manual Rule 88 as a means of operating a car past 40, however the car owner must still get a waiver from the FRA before operating the car past 50 years. In addition to inspections the car owner must replace all components such as brake valves, wheels, bearings, etc with new or reconditioned components when applying for the Increased Life Status. You would also have to find an AAR certifed shop who would take on the rule 88 project.