Thought I'd chime in with my experience here- I installed the kit on my 470 a month or two ago. This kit rides really well, on fire roads and bumpy mountain roads it feels just like the stock suspension which is amazing.
However, I measured before and after heights and only gained about 1-1.5" in the rear (noticeably lower than the "high" setting from the old airbag height control). It's installed on an otherwise stock vehicle, and heights were measured on level ground with half a tank and an empty vehicle. Poking around the GXOR page, it seems there's a few people who have also installed this lift and saw little to no difference in ride height. I'd love to hear your input on this Tanner, the rear springs are not quite what I expected.
Another thing to note is that the kit doesn't increase droop travel over the stock configuration. The limiting factor is still the sway bar end link. I plan to switch to a set of 2nd gen 4Runner end links to see if I can get to the end of the shock travel in droop. I did not measure how much longer the new shocks are compared to the stockers, but I'm curious to see if they offer more droop.
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