2 or 4?
2: Many cars has a rigid rear axle therefore in these cars we can align only the front wheels.
4: Lot of modern cars have multi arm rear axle, in these cars we had to align all the four wheels.
What it means?
Wheel alignment consists of adjusting the parameters of the wheels so that they are symmetric to each other to ensure that vehicle travel is straight. Correct wheel alignment will keep your wheels in line with your steering wheel. Keeps your tyres in top condition by reducing uneven tyre wear saving you money. It has an important role to play in keeping your car central on the lane.
Why I need this?
The car straight run depends on precise settings. When you use the car: for example the road surface errors hit the wheels or you need to go throughout the pavement edges or need replace any parts of steering chain, these parameters changing.
The bolts and nuts under the car can get a lot of water and dust from the road during driving. Wet screw threads retain dust so they do not dry out and corrosion starts. This is a slow process and should not usually be a problem. But what can we do if we can’t loosen the bolts / nuts when adjusting the wheels? First of all we clean the screw thread. And we use the rust remover after. In lucky situation we have enough time to wait for the result so, we can loosen the nut. Otherwise we need to try remove the nut immediately.
If it is unsuccessful, we have a spare plan. We are looking for the bigger tool or a pipe for make longer the tool handle.
If the result is same, we have a second spare plan.
We are looking for the gas blow torch and warming the nut.
At the end our third spare plan is the cutting disc. No more irresistible nut/bolt.