I recently purchased a 2013 F350 Lariat King Ranch. Highway driving is brutal when driving on concrete highways. No problems on asphalt. Any suggestions for suspension? It is really hard to take on long stretches.

 

In my opinion it's not the problem with your vehicle, its the suspension that behave differently on different surfaces as Asphalt and Concrete roads differ a lot. Your best option is to fine tune the existing suspension or go for suspension system with not so rigid characteristics.

 

I put Bilstein shocks and air bags all around on my 2011 F350 SRW and noticed an improved ride