64 patients with chronic, nonspecific neck pain were randomized to determine if the force applied in joint mobilization influenced immediate and short-term treatment outcomes. Patients were treated with joint mobilization of either 30N, 90N, or a placebo intervention. Joint mobilization of either force did not significantly impact pressure pain threshold or cervical range of motion. The group treated with 90N force displayed significantly less spinal stiffness than the placebo group at 2 to 5 days after treatment. Pain was also significantly lower with 90N force mobilization compared to 30N force mobilization after 2 to 5 days, although it was significantly higher with 90N force immediately following treatment when compared to the other two groups.