I took the leaf springs off two of these trucks and put them together should I get bigger rear shocks thank you for looking

 

Welcome to the site..

You added leafs to the Stack? If so, how many? Depending on how many miles are on the shocks, especially if OE, they may be ready for a change. If the leaf stack height was changed significantly, the available travel of the shocks would need to be checked..

 

there was four leafs and now there's seven leafs it raised the rear end up about four inches