When I did the lift on my Runner I didn't have shocks in the rear. That was a bouncy ride. It was scary to drive. It would bounce enough to unload the 63's & double shackle in the rear 

X2 except I didnt have front shocks either. For about a week I drove around town and pretended I had bags because if I pumped the brakes my truck would do the boat-rock. Got a kick out of it for a week but after putting shocks on (and driving on the freeway) I am glad to have them. It can be done but I much prefer having shocks. The bounce offroad wasnt pleasnt either but I know a lot of people that dont run them (ie half this thread  ) and they are just as happy without em. All depends, I DD my truck so I prefer to have shocks. weight makes a big difference too my truck is a lot heavier now in the rear and I think the shocks are worth having.