Personally, get the alignment done now, if not you're gonna kill your tires and defeats the purpose of spending the money on the truck if you don't get it done right.

That being said, it could entirely be your alignment lol. If your toe is off, during suspension travel different parts of the tires can grip and pull one way or the other, same goes for camber and all the others.

Could also be worn out steering parts or the tires you have one it too if they are a cheap tire, worn tire or steering parts have play.

 

Usually bump steer is caused by the steering components not running the same geometry as factory specs.. Like steering arm is now angled up more than it was during factory and with a 4 inch drop thats going to happen. The 4x4 guys run into it all the time when lifting their trucks and compensate with dropped pitman arms, x over steering, relocating steering components, all dependent on make of veh. With that much drop you may have been better getting adjustable upper and lower control arms not sure is cam adjusters for the alignment are going to have enough to bring it back to spec. Getting it aligned will help with bump steer but pretty sure it will not solve it never did on lifted veh

 

One thing that just came to mind... did u put new shocks in to match the lowering springs? If your still running OEM shocks I bet it bottomed out the shock when u hit pothole

Sent from my SM-G950W using Tapatalk

 

Wait a second. You went down like a Civic?? Theres your problem right there. you gotta go up!
Glad I could help bud!