Mid 80's to late 90's 2wd f150's. You can use earlier ones, but I prefer the mid 80's up because they come with teflon pads at the tips stock. They will give you some lift, but with the weight of a 4runner it won't be as much as the mini. The ones on my runner are from a '96 150, and i've also put in a 2" add a leaf for a little extra lift, and to firm it up a bit on mine. Another buddy of mine used them on his cruiser and he added some leafs from his stock pack to get the ride he wanted. As far as flex..... they are awesome. Of course they work much better on the front than the rear, just like any other spring does, because of the spring location on the axle and lack of weight on the rear, but they are big improvement over most spring options, especially when you consider how cheap you can get them.
