Note that the surface-projection-based method (KEYOPT(4) = 3) is not used to define contact between the rigid shaft and the rubber boot because this method does not support rigid surfaces defined by primitive target segments.

For problems such as an interference fit, over-penetration is expected. These problems often have convergence difficulties if the initial penetration is step-applied in the first load step. You may overcome convergence difficulties by ramping the total initial penetration over the first load step using KEYOPT(9) = 2.