Just bought the duramax 2005 diesel, the used truck. Found not that smooth as I was testing the truck before I buy it. Any way things I can do to increase the horsepower? do some chip tuning?

My friend gave me this truck diagnostic tool
On sale Xtool X-VCI for truck
and I dont even know what is this for. found no detail online.
Do you guys own this kind of stuff?

 

If it is not as smooth running as you think it should be you need to get it in for a diagnosis BEFORE doing any mods. You need to have it running right first.