Okla. Stat. tit. 47, § 47-11-602: Turning to proceed in opposite direction - Turns on

curve or near crest of grade prohibited.

A. Unless otherwise prohibited by law, the driver of a vehicle

shall not turn the vehicle so as to proceed in the opposite

direction unless and until such movement can be made with reasonable

safety and without interfering with other traffic.

B. No vehicle shall be turned so as to proceed in the opposite

direction upon any curve, or upon the approach to or near the crest

of a grade, where such vehicle cannot be seen by the driver of any

other vehicle approaching from either direction within five hundred

(500) feet.