Violent front end shaking

I don't have a fix but when you raise the front of your rig the tires most likely pigeon toe in and when you drop it back to the ground one or both tires may stay in a degree of misalignment due to several factors like tire pressure, tire type and condition until you drive it down the road and they find there center. If you take it to a tire shop and nothing is found. Try to observe the tire geometry the next time you raise it and you will see what I mean. Also next time when you drive off after having the rig up try steering back and forth while driving at low speed to center the tread back on the road way. Hope this makes sense to you and helps the situation.