I was thinking about buying a 2002 dodge ram 2500 diesel. From what I can tell it has about a 4 inch lift. I would be using the truck to pull horses. Would the lift affect the truck pulling?

I had the same truck w/a 6" lift kit on it and extra large tires. I was pulling a cigarette boat. The only thing it affected, other than making terrible gas mileage even worse was after I put an extra long drop on my receiver hitch, my boat swayed a little more than
It did before.
However, I did have a friend w/a transmission shop who told me that he loved people like me because the lift kit and tires were already putting an extra load on the transmission, then I made it worse pulling an 8,000 pound boat. I had the whole rig for about 2 years, and pulled the boat almost every weekend during the Summer and never had a problem.