<p>In this study, the effects of lubrication mode, counter punch end face angle, and counterforce on the hydroforming of curved diagonal tee tube are investigated to address the wrinkling and rupture defects caused by structural spatial multi-directional asymmetry. The experiment uses a flexible punch with a 70° end face angle to offer counterforce and multi-directional differential lubrication to address the multi-directional asymmetry of the curved diagonal tee tube. By analyzing the friction forces in each zone, the best lubrication method is found. This results in a differential lubrication scheme where the ratio of the lengths of the left and right lubrication areas is the same as the ratio of the distances from the two ends of the tube blank to the axis of the branch tube, the lower bulging zone uses a MoS₂-PTFE combination lubrication, and the upper bulging zone is coated with PTFE film. By quickening the flow of material to the bulging zone, this technique avoids wrinkle faults at the branch tube’s bottom and lower bulging zone rupture. When compared to a 90° end face counter punch, the 70° end face counter punch greatly raises the branch height, hence minimizing rupture flaws and improving the forming effect. Furthermore, a counterforce of 4. 24 kN raises the branch height while preventing rupture at the apex of the branch caused by significant wall thickness thinning.</p>