Yes. For P&W, four-digit engines are for large commercial aircraft. The first digit is the series, the second digit is application (0 [and sometimes 2] for Boeing, 1 for Airbus, 4 for McDonnel Douglas), and the last two digits are thrust in K-lb.
For R-R, the first digit is the series, and the last two digits are thrust in K-lb (shouldn't it be in KN
?).
For GE, only the GE90 has thrust rating as a part of the engine model, for example, the GE90-94B is a 94K-lb thrust engine, and the B stands for Boeing.