I was looking for this thread a long time and finally created an account here so can say thank you to everyone who posted these great finds and also provide a bit of feedback based on my install experience.
I have a '24 GX550 and a heavily modified '15 Jeep JK (had 4runners before those).
On the 'GX, I installed the 1" peak-suspension front leveling kit. It's marketed as 1.25" or 1.5", I measured 1" on my build.
A few notes about this whole lift/level/spring/shocks thread-
when you install longer coils/springs, you are not changing the overall shock travel.
normally, the shock limits your maximum droop as well as maximum bump travel. if all you change are the springs, what you are in fact doing is change the normal ride height. it simply sets a new point on your shocks where the normal ride height would be. your car's overall flex will not change.
in jeep forums, this will not be called a lift because it doesn't actually change anything about the wheel's range of motion.
this means there is no need to change upper control arms, drive shafts or anything. you are within original specs.
this also means that any tire rubbing issue due to running larger tires will remain. it'll just require some more flex to get to that point, but eventually the coil will compress all the way to the bump stop under sufficient load.
there are good reasons to go this route - it is simple. it is guaranteed to not interfere or stress any existing driveline component (since it doesn't actually change the overall wheel travel range), and it does provide a bit more clearance over 'easy' obstacles, like an occasional rock or some snow.
the peak suspension front spacer is not this. it actually pushes the entire shock and coil down, meaning you get an extra inch of droop in the front.
normally, you'd need a bump stop extender at this point because you pushed the entire shock down an inch, you risk having the shock limit your uptravel before hitting the bump stop. but peak suspension do not provide a bump stop extension, claiming that the OEM shock actually has more uptravel that is not used. they claim you actually gain an inch of suspension travel! keeping the original bump stop while pushing the down travel an inch.
i have not verified this claim on my build. i don't know how to easily push the suspension all the way to the bump stop to see how much shock travel remains. i'll post an update if i can ever prove this one way or another.
if you were to install some fancy king, fox or icon shocks, they'd actually be longer shocks that go along with longer springs. this gives you much more range of motion. this is where UCAs, shafts, CVs start to show stress. you'd need a diff drop bracket as a minimum.
few more points about the GX550 specifically and suspension changes-
the GX has auto-leveling headlights. there's a sensor somewhere on the rear axle that measures how much the rear is compressed. when you lift the car, it sends a signal to the headlights to aim higher. you can compensate by either relocating the sensor, or by using a small screwdriver and adjusting your headlights.
if you actually install longer shocks (remember- the springs don't affect maximum droop), you might need to check that this sensor and its wiring will not be damaged when in full droop.
the other thing about the GX is the front facing camera / collision sensors. these are calibrated for a specific vehicle stance. any suspension change technically requires recalibration. most garages can do it (any place that replaces windshields can do it). it's probably not critical to do if you haven't moved anything much, but it's something to consider. you need to consider this even if you only change tire size because a larger tire is a lift.
one last thing about alignment-
in an IFS, raising or lowering the front of the vehicle changes the toe. it's just the way IFS geometry works.
it's important that the toe be set correctly at ride height, which is where most highway miles are done.
i'm sure at least some of the claims about 'vibrations' and what not are actually due to misalignment and they're fixed after the suspension install because proper alignment was done.
specifically for toyotas, the shop doing the alignment needs to know 'toyota'. these cars are designed to be aligned with a driver and no other load. the 'toyota stance' is because the front left is designed to be about 1/2" taller when there is no driver in the car.
from what i'm reading here - the rear shocks are a bit stiffer and the fronts are longer. i'd probably install the rears to get better handling, especially since it's easy to DIY and i already have the peak-suspension front spacer which is an actual 1" lift, not just changing the ride height.
pictures for attention - first one is me removing the skid plates before installing the peak spacer.
next two are my jw-offroad front bumper install. i try to DIY whenever I can.
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