I have a 2018 ram 1500 4x4 just wondering what is a good exaust system and what is a good 4in liftkit basically what gives the best bang for the buck

 

Exhaust wise, I think the best way to keep your stock piping intact with quality parts and good sound are either a Mufflex set up or a Carven setup. Both are drop in and bolt up systems that retain the stainless steel aspect of your factory system. I am running a DOD24M Mufflex system and I have been happy with it over the 40k miles its been on. It still in great condition., too.

As for lift kits you can go multiple ways. BDS, Rough Country, Readylift are a few with 4" offerings. I am not overly familiar with the lifts as being the best bang for the buck, though.