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What is more caster?

JBA upper control arms have more caster for the lifted vehicles.

Let's explain what caster is first.

Factory alignment specs for basically all vehicles call for a certain degree of positive (shown below) caster. This ensures good stability, helps maintain straight-ahead direction and promotes steering wheel self-centering. Camber is the inward or outward tilt of the front tires as viewed from the front. Toe-in is the amount the tires point in at each other from being parallel with each other. 

front end terms

With the Toyota market most of the JBA UCAs have 3 degrees caster built into the arm, so the top of the steering knuckle moves back giving more caster with a lift kit.

Also the higher you lift an IFS vehicle the less caster you will have and adding 3 degrees to the upper control arms will fix the caster lost from lifting your vehicle. Tell the tech to set the caster between 3 & 4 degrees when doing the front end alignment.