I would like to check the financial health of my pension fund by
obtaining credit reports from the major rating companies. I have
searched Google and not discovered a way to do this. The pension fund
is:
American Federation of Musicians and employers' Pension Fund.

As far as I know, the rating agencies don't rate pension funds. As a
plan participant, however, you are entitled under law to copies of
certain financial and related information about your plan and its
funds. Ask your plan administrator to give this information to you or
to tell you how to obtain it.

The following Web page on the site of the US Department of Labor may
be helpful:
 http://www.dol.gov/dol/topic/health-plans/erisa.htm