Difference between TSB leaf and Non

I would like to know what the difference is between the TSB leaf springs on the 2nd gen Tacoma vs the non TSB? I know the TSB leaf pack has a total of 4 leafs, what else?

 

4 leafs, it has a high weight capacity and like 1/2" more lift in the rear. Other than that, no difference really.

 

Reason I ask is that I see companies like Toytec want to know if the springs are TSB or not before ordering an AAL

 

That's because the AAL has to be designed to fit into a 4 leaf pack or 3 leaf pack so they are slightly different design. Also all TSB AAL's only add 1.5" because you already gain 0.5" from the TSB leaf pack. Most non-TSB AAL's add 2" with a few 1.5" ones out there.