So I didn't get the TRD springs installed at the dealership when we got the XB. If I don't get the lowering springs istalled at the dealership will it void the warranty? Just asking cause I've had problem with past cars and dealerships blaming the lowering springs for any problem the cars had.

 

There's a whole thread on that topic:

The truth about voiding your warranty
https://www.scionlife.com/forums/maintenance-car-care-1604/truth-about-voiding-your-warranty-21642/

 

in a nutshell, yes and no.

when most TRD parts are bought new and installed by a dealership, they join the factory warranty that the car came with, when they're bought new, but installed by a 3rd party, they only carry a 1 year/12k mile parts warranty, which is to say that the parts themselves are warrantied against defect, but if something else is damaged and the route of the damage can be traced to those lowering springs, it is not covered.

 

A dealership CAN NOT void your warranty, they can deny warranty work being done to your vehicle.