Do you have an automatic or manual transmission? If it's a manual, the flywheel is pretty tough and hard to imagine it cracked around the center. I'd more likely expect to find the bolts sheared off, and even that would not be common.

If it's an automatic and uses a flex plate, they can crack around the crankshaft bolt holes. If it is broken you should hear the starter spinning, and often there will be a clanking sound with it. Check if the bolts are still intact between the torque converter and flex plate. On GM vehicles the ring gear for the starter is on the flex plate so missing bolts will allow the engine to crank and run but the transmission won't work. On Chryslers the ring gear is on the torque converter so missing bolts will prevent the engine from turning during cranking. I don't know which way yours is. Either way the transmission will have to be removed. If you've never pulled a transmission, get the manufacturer's service manual. There will be pages of steps listed with drawings. Most of those steps aren't very hard; they're just time-consuming. Be sure to use jack stands to support the vehicle well because weight will be shifting and you'll be tugging on stuff.

Answered by caradiodoc (expert)
17,264 answers provided