I pulled my rear Icon 2.0 at 13k. They started leaking at 10k. We use the vehicle for real though so I am not complaining. Just an explanation of the shock and its pros and cons. And, by extension, of other 2.0 IFPs.
I ordered a vise on Amazon. Well, what came was kids size! I broke it before I had finished disassembling the shock and the so-called vise was never useful anyway, lol. That, thankfully, was the only hiccup.
Tools you need:
--needle to get the nitrogen out. I got a motorcycle charging tool for 50% the price of the Icon one. Already broke one of the two needles, so having more would be helpful.
--Good vise will help but you can do without.
--You absolutely need a spanner wrench with 4mm pins. I bought one off Ebay for 8$ and feared it might break. Instead, the vise broke. Maybe this will when I do the other shock?
--You need a pick for the retainer clip.
--You need a threaded something to pull the IFP out. You can buy a pricey specialty tool or go to HD or Lowes and get two sizes of threaded 24" rods like I did for 3$ total. The smaller one fit. Will update with size if I remember...so, yeah, 1/4 in.
Except for the annoying economy needle part, the rest is as on any Youtube video you can watch. Also, the pulling of the IFP is harder as it is very deep. Slowly but surely it came out.
This overviews the piston and the valving:
Icon Vehicle Dynamics - 2.0 Digressive Piston Review | AccuTune Off-Road
It was interesting to see first hand that two-faced piston. The compression side is completely flat/linear with just one bigger and two smaller, equal in size shims. The rebound side is digressive, mildly so per Accutune. Has four shims and two stacked, identical retainers.
The exterior tube is exactly 50mm in dm with 45mm interior dm and the piston is therefore only about 43mm. In comparison, Bilstein advertises my front pistons as 60mm (the body is 2.65" or 67 mm). The same is true for the 8100s I am awaiting, eventually.
Things get interesting when you consider lengths. The exposed shaft is 9" (vs 8" for the Eibach rear shocks, which are my spares). With 1" Eibach rear spring, the shock has 4" of exposed shaft at rest with a HUGE 5.25" of downtravel. But because the Icon 2.0 is optimized for 2" rear lift, up travel is only 2.5" as travel stops with 1.5" of exposed shaft. The limited jounce is felt big time over choppy terrain. Inside, the rod's top bolt seems to hit the IFP around the small vehicle dynamics letters under the big ICON letters.
And this is why you should only run IFP shocks that are at their ideal position at rest. This, of course, assumes offroad use. Reservoirs can help with imperfect sizing. Reservoirs, of course, remove the nitrogen from the main cylinder, allow consistent pressures and lower operating temps, thus increasing both longevity and comfort. Adjusters add, duh, adjustability, but also secondary valving and are thus useful even if you don't, eh, adjust them very often.
So here is where I am partying ways with my indirect mentor,
@
Jetboy
, lol. Maybe the IFP rears work fine on dirt roads passable by CUVs at lower speeds but get into that mid-range between low range offroading and true high speeds and the rear IFP gets way over its head. That can also happen in Utah, like it did to us on the middle section of Smoky Mountain, the 15 miles or so with embedded rock. That kind of terrain, unless you want to crawl it like a car would, is just too much for a small IFP shock.
For the rest, the Icon 2.0 is a superb shock for the money, all 160$ of it. Interior components look extremely well machined (though this ain't my area, not by a long shot).
The Icon 2.0 is King of Pavement: control is always superb, which is not true of the Eibach rear shock. Try going through a bump with only the pax side wheels. The Icon keeps the rear wheel GLUED at all speeds. The Eibach cannot do that though it seems to improve as speeds increase. Similarly, in corners, the Icon is a, okay, shocking shock. With 6112s and Icon 2.0s, and Mickey Thompson ATZ P3 tires (!), the 4Runner feels better in a corner than a brand new Subaru Ascent with low center of gravity, quality AWD, street tires, you name it. And I am a Subaru fan, for the record. The Ascent is a great CUV! By contrast, the Eibach, while WAY better than stock, cannot keep the rear tires from feeling as they would want to break free. None of that matters 99.9% of the time in town or on the interstate, but if you drive on mountain or coastal roads frequently, it will.
Offroad, the Icon 2.0 performs very, very well.
@
Jetboy
is right--to a point. You can run with it. The rear tires remain always planted where a stock rear would be ALL OVER the trail/dirt road. I am serious, not overstating anything: apples to apples comparison in 2wd. But while the Icon can GO, it cannot do so for very long. And comfort is in short supply in the rear seat. It can take big hits, indeed, if the rear tires come nearly airborne, it takes the resulting hit from nearly full extension extremely well: that's when the Icon really feels comfy.
So, there you have it folks, great shock for the money--the little shock that can--but resi are a must for serious offroad use and shocks should be perfectly matched to rear lift (and not, yeah, it is good from 0 to 3" lift).
No spare parts or oil were available when I tried to order, so actually rebuilding this may or may not happen any time soon...but it was fun to open one and see exactly what happens.
Also, the Eibach shocks are fine shocks and a huge upgrade over stock, don't take me wrong, but the Icon has an edge. Of course, it makes sense, while the price difference does not sound like much in absolute terms, it is about 50% premium.
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2018 TRD OP non-kdss, well armored, well used
(6112s/650lb at 1.3" lift, Icon 2.0 and Eibach 1" rear, Mickey Thompson ATZ P3 LTE 265 70 17, RCI set of front 3/16 skids, Shrockworks step sliders and 3/16 steel gas tank skid, C4Fab rear diff skid, Rockmen rear LCAs, Total Chaos rear LCA bracket skids).
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