On page 101 of Savage Worlds Deluxe is a table for critical hits when dealing with vehicles. However, I can't find what would cause you to roll on this table. How do critical hits on vehicles work?
Reading Vehicular Attacks, Damage on page 110 of the Explorer Edition or page 100 of the Deluxe Edition, car damage works like this.
If you roll enough damage to "shake" a vehicle, it is not shaken, but instead forces the driver to make a Driving test or roll on the Out-Of-Control table. A raise on the damage test actually wounds the vehicle giving all actions with the vehicle a -1 modifier. Each wound also causes you to roll on the Critical Hits table. The fourth wound wrecks the vehicle.
It can take a lot of damage to wreck a vehicle, but realise that going Out-Of-Control can completely remove a vehicle from play if you roll well on the table. As a GM, I almost lost an aerial drone into the side of a building from an otherwise undamaging shot just last weekend.