This week on the Best of Car Talk, should Heidi let her husband change her Volvo's timing belt? Before you answer, we should tell you that Heidi's husband is a tennis pro, with no repair experience, and that messing up this job will kill the engine. Wanna rethink your answer? Elsewhere, Craig's girlfriend's mother bought him a new truck. If Craig breaks up with the daughter, is it also splitsville with the truck? Also, Nathan dinged his girlfriend's Civic while driving it without a license—or her permission. Can Tom and Ray help him fix the car's thunk before the next sound is her giving Nathan a dope slap? All this and more, this week on The Best of Car Talk.