General Motors Corp. yesterday reported record third quarter profits, although only 13 per cent higher than last year, while third-ranked Chrysler Corp. surprised analysts by its 55 per cent decline in earnings.

General Motors said profits rose to $402 million ($1.40 a share) compared with $397 million ($1.37) a year ago. Sales rose to $11.43 billion from $10.16 billion.

The industry giant, which in the second quarter became the first U. S. industrial firm to have profits of more than $1 billion for a three-month period, also reported its unit and dollar sales set records from July through September.

GM attributed the figures to a continuing strong market demand for new cars and trucks.

Earnings for the first nine months increased 14 per cent to $2.4 billion ($3.36) from $2.1 billion ($7.31) for the period last year. Sales rose to $39086 billion from $34.11 billion a year ago.

Chrysler Corp. reported third quarter earnings of $30.4 million (51 cents a share), down 55 per cent from the 1976 third quarter results of $61.2 million ($1.01). The figures were much lower than financial analysts had predicted.

Chrysler had an extraordinary income tax credit of $3.3 million (5 cents) in the quarter compared with a similar credit of $15 million (25 cents) a year before.

For the first nine months. Chryster earned $184.2 million ($3.06), down from $234.4 million ($4.04) in 1976. The figures excluded income tax credits of $28.7 million (47 cents) this year and $60 million ($1) last year.

Wall Street analysts had forcast a third quarter profit of about $50 million for Chrysler.

The statement to stockholders reported worldwide dollar sales in the third quarter of $4 billion from 726,995 cars and trucks, versus $3.8 billion last year from 740.203 last year.

For the nine months. Chrysler had dollar sales of $12.5 billion, campared to $11.5 billion. Unit sales worldwide this year were 2,343,513, compared with 2344,555 last year.

Chrsler's share of the domestic auto market through Oct. 20 of this year was 13.7 per cent against 15.4 per cent in the comparable period last year. General Foods Corp., the nation's largest manufacture of packaged foods said lower coffee prices contributed to its 37 per cent drop in second quarter earnings.

Quarterly profits fell to $28.4 million (57 cents a share) for the same $44.9 million 90 cents) for the same period last year.

Sales rose 9 per cent to $12 billion from $1.1 billion.

For the first half earnings declined to $79.2 million ($1.59) compared with $97.7 million ($1.96) for the same period a year ago.

James I. Ferguson, chairman and chief executive officer, said on a worldwide basis coffee volume dropped about 35 per cent from last year's comparable period, as a result of grocery trade and consumer pantry stock liquidation as well as a decline in consumption.

The near-term prospects for the company are uncertain because of the world coffee situation and as a result, our earnings for the year endings of the last fiscal year," Ferguson said.

General Foods manufactures Maxwell House. Yuban and Sanka coffees.

Gulf & Western Industries said lower sugar prices contributed to a drop in fourth-quarter earnings, although they were the second best in history.

For the quarter, the company earned $23.1 million (43 cents a share) on sales of $931 million compared with $47 million (94 cents) on sales of $866 million.

For the year, G&W earned $150.3 million ($2.99) against $190.1 million ($4.04). Sales rose to $3.64 billion from $3.4 billion.