Texas Eastern Corp. restated its earnings.

The Houston-based oil and gas firm said the change, which reduced its retained earnings at the end of 1985 by $139 million but increased its first-quarter results, resulted from a change in its accounting method. Texas Eastern also said it might have to cut its 55-cents-per-share quarterly dividend because of the collapse in oil prices. Earnings for the first quarter of 1986 were restated to $37 million from the $6 million reported earlier.