Pa Joad may be the patriarch of the family, but he sure is a quiet one. Having fathered six children and having lived in Sallisaw, Oklahoma for all of his life, farming the land, Pa Joad has his hands full. He isn't always the best at staying calm or at making decisions, but he does the best that he can. Marrying Ma Joad might have been the smartest move he's ever made.
We notice that Pa Joad gets quieter and quieter as the journey unravels. Here and there, we catch glimpses of how he might be changing. For example, when Ma Joad demands that the family not leave Tom behind with the broken touring car, she has to arm herself with a weapon. In the old days, Pa Joad would have beaten Ma Joad for talking back or for disagreeing with his decision. But times have changed, and Pa, who has lost almost everything, is more bewildered by the change he sees in his wife than he is angered by it. In fact, as the novel unfolds, Pa grows more and more bewildered by just about everything he sees.