I wanted to convert my to 4WD. The best way is a frame swap which presents problems of its own.

Then I remembered. These trucks go just about anywhere, even in the snow. If you actually need 4WD, do you really want to go there with your truck????

I plan on using BF Goodrich Commercial T/A Traction tires. They are mud and sno rated with the mountain snowflake symbol which means severe weather use. They will look awesome and last a long time. Not the cheapest though. MADE IN USA!