Hey ya'll! Quick question...

At speeds over about 65 on the highway, my 99's front end will start to shake uncontrollably if I hit a bump a certain way, and get worse until I get the vehicle to a complete stop. Tires are not oversized, but it does have an old 3" skyjacker lift on it...

Couple thoughts... alignment? bent half shaft? It seems to be happening more often lately... anyone ever had this problem? Any suggestions would be much appreciated!