What lift

I recently bought another tacoma it is a 15 TRD Offroad. The person before me hadown put a levening kit or lift in the frontop because it has 285/75 tires but didn't put anything in the rear. What should I get blocks or add-a-leaf and will stock shocks work.

 

I'd get in contact with @ToyTec Lifts about what the best option would be for you.
The aal should work out just fine with stock shocks, but would be a good recommendation to get new ones down the road.

 

Stock shocks will work, but like David said i would recommend replacing those in time if you do decide to lift the rear. As far as which lift to go with, its up to you. The block will keep the same ride quality but raise the rear end whereas the add a leaf will slightly stiffen the ride but be better for the truck overall.
Give us a call here and we can walk you through any questions you may have.