First off, the bellypan that DTHVLY posted is probably okay for a 4Runner.....(anyone know the thickness?), but for *most* vehicles, it's going to need to be alot thicker. On my old Toyota pickup, I personally wouldn't have run that without some sort of additional support, but depends on your use and I admittedly don't know if that unit replaces the factory tcase crossmember entirely as so many Toyota specific skids do.
The stock Hummer one has a lot more rigidity than that sheetmetal one. (Sorry for calling it sheetmetal, but it *looks* thin from the pic). Even if it's 1/4", I'd bet spanning that great a distance on the belly of an H3, it could easily bend in the right environment. Will it still protect your components? Probably, but it's still mashing the tcase up into the floor pan (if you remove the factory crossmembers and use it solely....which I don't think anyone is advocating). The best route is a tubular frame with 1/4" plating. That way the plating does the skid work and the tubing supports the vehicle weight. If the skid that was pictured was actually for an H3 and kept the factory crossmembers, it *could* work....again, depends on the use as well as the distances spanned. Keep in mind though a skid that size will be HEAVY....which can be a good thing if you have enough engine to move it and if you want a
negligibly lower CoG.
And I'll agree with Woody....keeping your vehicle as low as possible to clear as big a tire as possible (that your axles can handle) is the right way to build an offroad truck. The "generic" formula for keeping factory stability is usually considered to be "for every inch you lift a vehicle, the track width should be widened by 1.5". So, if you put a 6" lift on, your track width should be 9" wider. Obviously, this "formula" will differ from vehicle to vehicle....it's a generalization that is VERY hard to actually make happen on most vehicles. If someone wants the actual formulas for figuring your CoG, I can link it and then someone with a stock truck vs. a lifted one with offset wheels can do a comparo and we can put the argument to bed. Any takers? We need someone with a stocker, someone with a lifted one and both of them need to be completely honest and able to follow instructions (as well as be able to fab or rig up a set of rigid links to replace the shocks). It will be time consuming, no doubt. ***EDIT*** The one thing we'll need to decide though is: are we really wanting to know CoG or the roll center...or even the roll angle? The tests will change based on what you guys are really wanting to know.
***EDIT***The one thing I would cautiously disagree with Woody about is his comment about
"Sometimes, you are going to wish that your vehicle wasn't lifted so high." I'm making the
assumption that he's in effect saying that it's better to leave the vehicle stock.....the problem is (especially with a full bodied vehicle): you have to lift it to clear the tires you NEED to run the trails you want. Yes, you may end up paying in terms of stability, but it's one of those tradeoffs you have to make to have the vehicle do what you want (and maybe that's what KenP and Paragon are trying to say). Your only other option is to break out the plasma, sawzall and welder and it would seem that most Hummer owners aren't quite ready to take that leap....yet.
****
As for overheating with a skid pan.....How do you guys that are saying that come to that conclusion? What exactly are you overheating? It certainly isn't going to be the engine. Yes, you may heat up the floor boards and any wiring in the covered area more (especially if the catalytic converter is housed between the floor and skid), but it's highly unlikely that there's anything that will be damaged by the
relatively minor increase in temperature....and that includes the transmission and tcase. Again, easy test if we can find a few volunteers....one equipped with no skid and one with a skid in the same local area. That is, if you guys
really wanna know for sure instead of merely speculating about something with which you have no experience.
All you guys claiming that rocks never get stuck between the factory UCP bars, obviously don't wheel where I do. That design's a liability, but it's easily solved with some plate if your brand of 4wheeling necessitates it. And yes, it does make it harder to clean up (as well as service).....I'm willing to sacrifice a little inconvenience for better performance and protection.
Oh, and Liberty's are bad ass.
Here's mine.
It's got a 1/2" thick, 12"x25.5" skid under my tcases. It also protects the front and rear drivelines (to an extent; the lower links do the rest since my DLs are both above the lower links). The only overheating problems I anticipate will be having the exhaust running so close to my floorboards....but that's why they make header/exhaust wrap and floor insultation that's only 30 thousandths thick and is heat resistant to 2100º. Just route any wiring away from this area or encase it in fire-retardant loom (275º heat protection)....all these products cost less than a bill total.
Sean
***EDIT*** Any chance "Paragon" has a (I think) yellow H2 that he posted pics of on Pirate4x4.com where he was climbing Escalator? If so, I'm the same "Sean" that sent you a PM about all the a-holes making snide comments in your thread. If it's you....hope all's well. :wave: (guess you guys don't have the "wave" icon).