I presume by 60/40 you mean the pension funds should lower risk.

If they lower risk, they are not going to get close to their presumed 7-8% growth. Expected stock market growth rates is around 5%(https://www.cnbc.com/2019/02/11/vanguard-cuts-expected-retur...) Rate of return on bonds is even worse.

Assuming this is correct, the choice is either increase contributions, or decrease payouts.