MDA is a man-made (synthetic) recreational drug noted for its stimulant and psychedelic properties that has been used since the 1960s as a clubbing and sex-enhancing substance, with some similarities to LSD and MDMA (ecstasy). Sought after effects. 1  visual hallucinations.
A wheel alignment is done to make sure the vehicle's wheels are running parallel to each other, and that the tires meet the road at a correct angle, to fix or avoid problems such as irregular tire wear, poor handling (pulling to one side) or a crooked steering wheel.
You can tell if the wheel bearing is shot by jacking the truck up til the wheel is off the ground, grabbing the top and bottom of the tire and try to pry it in and out. ANY movement is wear. A stocker will not move. Ours were worn to the point of more than 2 slop at the tire with 50,000mi on the truck.