Are a cars tires parallel

Answer 1

Depends on the condition of the car, the design of the car and the driving conditions.

Ideally they should be, but there's a bunch of things chat can change this.

In a front wheel drive car in good condition, the front wheels are aligned to be parallel under power. Since suspension parts flex a bit, this means that the front wheels will be a little bit toe-out when the car is coasting, and a bit more toe-out during braking.

If it's a rear drive car, front wheels will be parallel while coasting, but toe-out during braking.

Rear wheel alignment will also vary with design. Cars with solid rear axles will have rear wheels parallel with each other, and mostly parallel, but not necessarily in line with the front wheels.

Cars with split rear axles will usually follow the same toe-in/out variation as front wheels depending on if the car is coasting, braking or under power.

Then there's the question of suspension travel. Sometimes toe-in/out varies a little as the shocks and springs in the suspension allows the wheels to travel up and down. It's hard to get the linkages just right and to have the car track perfectly even when hitting a bad bump.