All of the negative statements in this video apply to my 2021 Fiat Panda hybrid .. around the village the steering is great .. BUT on a level windless main road the steering has a mind of it,s own . Get used to it I was told . Maybe it was gusty winds .. Pay for an alignment . The Fiat is under warranty why should I have to fork out for an ALIGNMENT. I have bought a caster / camber instrument .the camber is 1- 1/4 degree negative on each front wheel . caster on each front strut is 1- 1/2 degree. 20/ 20 steering swing .
Shopping trolleys don't have negative caster, I don't know why this keeps getting repeated. The swivelling wheels have zero caster but instead have a trail from the caster pivot to the wheel axle. The effect is the same as positive caster, it keeps the wheels following the direction you are pushing the trolley. Shopping trolleys behave unstably because you have no steering gear allowing you to hold the wheels straight as you would in a car , and because they usually have 4 swivelling wheels. So the castors can be influenced by cross gradients rough surfaces, dirt stuck to the wheels making them wobble or the cart will follow a cross gradient, or if you change direction 180 deg then you do have negative trail untill the castors swivel round to follow the new direction making the behaviour of the cart unpredictable during that time.
