The question sounds like the woman is alleged to have lifted a 1.5 ton weight into the air, like a weight-lifter.
Her claim is much more mundane - that she was able to shove the weight in a way that relieved the pressure from her father, and enabled him to be rescued.
thanks to the unevenness of the car due to the tire having been removed, Lauren was able to shove it hard enough to tip the car off her father and drag him out of harm's way
A shove against the car, tipped unevenly like a four-legged table with a short leg, was enough to relieve the pressure. She pulled her 210-pound, unconscious father from beneath the BMW.
(Wikipeda confirms that a BMW 525i E34 has a curb-weight of 1.5 tonnes, although it may vary by model and by what was in the car.)