In this paper we study the class of w-Jaffard domains in pullback constructions, and give new examples of these domains. In particular we give examples to show that the two classes of w-Jaffard and Jaffard domains are incomparable. As another application, we establish that for each pair of positive integers (n, m) with n + 1 ≤ m ≤ 2n + 1, there is an (integrally closed) integral domain R such that w- dim (R) = n and w[X]- dim (R[X]) = m.