Car warranties can be confusing, and consumers may not realize the difference until something breaks down in the car. When one purchases or leases a new vehicle, the vehicle comes with a 36,000 mile or three year warranty. The bumper-to-bumper warranty typically covers everything in the car. If the radio stops working properly at 20,000 miles and you've been in the car less than three years, the manufacturer will cover the repairs of the defective part. If bearings go out at 30,000 miles and you've not yet reached the three-year mark of ownership, the bumper-to-bumper warranty will take care of that cost as well.
The powertrain includes the engine and transmission as well as the driveshafts, the differentials, and all other internal workings of the engine. The powertrain warranty usually stays in effect for 100,000 miles or ten years (again, whichever takes place first). Repairs to these engine components are covered under a powertrain warranty.