The bank had named a special group of outside directors to review its loan-loss reserves.
In addition, $360,000 was put into loan-loss reserves to maintain a conservative position.
Trustcorp also recently added $24 million to its loan-loss reserves.
All four banks also increased their loan-loss reserves, in some cases sharply.
Chase added $1.6 billion to its loan-loss reserves, resulting in a projected 1987 loss of $850 million.
The decline in profits at the banking company was caused by the addition of $160 million to its loan-loss reserves.
The company added $75 million to its loan-loss reserve, the same amount as in the previous quarter but down from $200 million a year ago.
Declines in the amount added to loan-loss reserves increase bank profits.
More banks added big sums to their loan-loss reserves for problem third world debts.
Chemical assumes it will have to add $1 billion a year to loan-loss reserves for the next four years.