Here is how it goes. Everything is 3/16 steel. I have now taken off and re-installed the front package skids twice, so total of 3 installations. I have taken off and re-installed the gas tank skid once. I paint and treat the metal as needed and chase the frame holes.
RCI front skid package: engine, transmission, transfer case + front filler plate. The entire package is simple to install but a jack helps a lot.
The engine skid was frequently used before stiffening the front suspension. Barely used since. Two very hard hits at speed. One was from a rock on the other side of a very smooth uphill towards the end of a long day. This bent one of the interior vertical supports (those in the middle). The other was caused by the unexpectedly soft standard 6112s which dove on a rock I was sure I would clear. This was the reason for upgrading the springs. The hit completely deformed 2/3s of the front edge and the area immediately behind it. The oil change port is also deformed. Yet the entire skid and the port remain fully functional and the latter hit even improved the clearance, LOL. It is a big bonus that RCi retains the radiator supports. The skid bent around the pax side support which remains like new. While the skid could have been wider to cover the alignment bolts I have had no issues with those (I have replaced the rear lower shock bolts deformed by all the rock bombardment from the front wheels but not issues with bolts up front).
The transmission and transfer skid have been used for sliding a few times and the latter has taken a lot of minor hits due to the poor breakover angle. But I don't think either has suffered a big hit like the front one has. No issues.
RCI front skid package verdict: would repurchase any time.
Shrockworks Gas Tank skid. This is a tough one to judge. I purchased Shrock because RCI's old gas tank design was weak on the front edge, which is where hard hits are likely. The skid is extremely strong but an absolute pain to install. It uses the rear interior strap support bolt. Undoing that one is no biggy but installing the strap within the Shrock support bracket is very tricky: you have to support the tank gently by a jack which means the strap is pretty much at the needed height. But it is away from the hole of course. So then one hand has to hold the bolt and try to get it through while the other hand has to place the strap into position within the bracket. It is not too bad if the strap is at the needed height: you only adjust it horizontally. But others use the factory bracket design, which is further back. Adding insult to injury, the skid uses stick nuts on the outside for no reason I can fathom. I refused to bother and drilled instead new holes so I can use the threaded holes in the frame.
What a mess this skid's mounting hardware is!
On to function,
the Shrock skid is a very mixed bag. OTOH, it is very strong and took like it was nothing one very hard front hit to go along with a couple lesser ones. OTOH, mine rubbed on the gas tank over most of its surface. So it
protects from hard hits short term, but slowly destroys your tank long term! Problem is, this likely happens with other gas tank skids as well. While Shrock does offer some adjustability I needed 0.5" more which required some ugly DIY garage mods. Now I have proper clearance. I am considering adding a rear outside support bracket. We will see.
Shrock gas tank skid verdict: very strong but the insufficient adjustment for clearance is a potentially fatal flaw (if you fail to notice) and the mounting is ridiculous. I am sure there are worse options out there, but if I had to repurchase I would try RCI's new design or maybe C4's.
Shrockworks Step Sliders. These share some of the silliness of the gas tank skid in that they use tiny mounting plates and stick nuts on a frame full of threaded holes. This means unnecessary frustration and, worse, the front edge is barely strong enough, and the rear edge surely isn't: the sliders bend into the rocker panel if you try to jack from the rear end. I had an extra leg and plate welded to the pax side slider in the front.
Use is hard to review because most hits have been self-fulfilled prophecy: in most cases, I would not have hit anything had I not had sliders (they eat a lot of clearance). However, the positives outweigh the negatives: the sliders are strong enough for normal hits and have helped me for real on a few spots both in rocks and between trees. So they have done their job on trail.
Beyond the trail, the Shrock step sliders offer fantastic powdercoat (though underneath there is more paint now than coating), a comparatively great price, and a functional step.
Since the positives far outweigh the negatives, I recommend the Shrock step sliders. They may not be for extreme rock crawling but that's not what 5th gens do anyway. Just make sure you drill that hole for the front pax side slider
.
C4 rear differential skid.
This one is a great design that covers as much as can possibly be covered. The one hiccup I had was with two bolts that I feel should show less thread. Regardless, the skid has been on for a long time now (though less than the others) and many trails. It feels rock solid. It has taken mild hits only but I would rather be safe than sorry.
Rockman rear LCAs and Total Chaos bracket skids. The former are an insurance against bigger ledges. The latter have been the most used skid on my vehicle, especially the pax side skid. Total Chaos had not machined my set well enough which slowed down the installation but
these skids have been golden for me.
So there you have it. Whatever gas tank skid you buy, watch out for the clearance between gas tank and skid.