When it comes to self-driving cars, Alphabet's (GOOGL) Waymo is the leader, not Tesla (TSLA) , according to TheStreet's founder and Action Alerts PLUS Portfolio Manager Jim Cramer.

Morgan Stanley tech analyst Brian Nowak said Tuesday the Alphabet owned autonomous driving unit Waymo may be worth $175 billion instead of his prior estimate of $75 billion.

"Alphabet is probably my favorite big-cap stock right now," Cramer said.

Alphabet is a holding of Action Alerts PLUS.