1997 Oldsmobile Silhouette Question: Code P0753 - how difficult to repair?

I have checked the cost of the part, and it is around $30.00. Wondering how labor intensive is it to fix. Also, it an intermittent problem, doesn't happen every time shifting from first to second, and doesn't happen at all once I get over 25 mph, if I do not repair immediately, will it cause additional problems or a breakdown?