Resistance after installing kit

[Mr.Jack]

Hi.

I had a leveling kit installed yesterday by my dealer/garage. But I feel that after this install, there is more resistance. (I have not changed the tires/wheels.)
It seems that I have to add more engine power than before to get the truck moving.
Is this something I am just imagining myself, or is there a way this leveling kit can affect any resistance?

 

[Z-56 Hoe]

Other then more wind drag I don't see how.

 

[Vette66]

Not sure if this is the issue but check the angle of the rear end. If they did it wrong it could be angled so it binds the drive shaft. Just check it.. I have seen somebody put lowering blocks on there truck and not know that the axle has divots or a pin that needs to be placed right. It caused his axle to tilt up and but the drive shaft in a bind causing his clutch to go out about a week later ect....