Taking The Torch To Your IFS swinging A-arms and letting the halfshafts drop into a pile on the garage floor isn't as scary as it once was, but getting everything back under there is still a challenge. Luckily the off-road aftermarket and enthusiasts have done enough research that you shouldn't be scared of the challenge.
Around the mid '90s guys started seriously modifying their 4x4s as the solid-axle swap craze came to be. At first it was an exclusive undertaking of expert fabricators with the cajones to cut their IFS truck apart in hopes of making it better, but over the past few years solid-axle swaps have become so commonplace that they're attempted in driveways across this nation, and often done over a long weekend with some serious prep and a dedicated crew of mad fabbers.
 The Red Sled has been through...  The Red Sled has been through some arduous testing, but it rarely made it longer than five minutes off-road. We jumped it in the dunes shortly after getting the new big-block and 6-inch Tuff Country suspension installed, but that resulted in a broken passenger-side halfshaft. |  A few weeks later we took...  A few weeks later we took it on an easy run on a muddy trail, but that also resulted in a broken passenger-side halfshaft. Note that at this time we had an ARB Air Locker in the front 9.25-inch ring-and-pinion differential under the truck. |  After a few more tests that...  After a few more tests that resulted similarly, we upgraded to a set of Rough Country halfshafts (bottom two). These have a slip spline and fixed CVs at either end since we felt we were overextending the halfshafts on the passenger side and causing them to bind and explode. |
Now before we go another step let's stop and think for a second about the millions, and we mean millions, of dollars spent to design and engineer that independent front suspension. Many very smart people working in OEM engineering studios from Detroit to Japan have made it their goal to offer us a flexible front suspension that allows each wheel to move independently while still carrying the load required. Unfortunately they have not yet come to market with a wobbly front end that can hold up to the real-world abuse that off-roading dishes out. Understand that these guys have to answer to the American buying public, who told them that a comfy ride is more important than an axle-and-suspension combo that will survive the barrage of battering and masochistic misuse that we wheelers like to dish out. As such, they build what sells and what their marketing people tell them people will buy, and we do just that.
We buy their trucks, drive them for a while, take them off road, break all that fancy double A-arm wambly jambly stuff and then drag it home, fire up the plasmatic super cutter, and leave all their millions of dollars in engineering sitting in a smoldering pile under the framerails before rolling a good old solid axle underneath and fashioning up some sort of leaf-spring mounts or coil/linky system.
 We took the Sled for another...  We took the Sled for another alignment at this point. The many parts of the IFS were not holding up to the short-term abuse off-road, and resetting the alignment to keep the tires in one piece was getting annoyingly common. |  One of those early trips resulted...  One of those early trips resulted in the rear driveshaft getting twisted like a pretzel, so we pulled it free and drove the truck home on the front diff alone. We can say that IFS drives nicely at highway speeds if you need to limp home without a rear driveshaft, but we don't recommend it for any length of time. |  We had been running 35-inch...  We had been running 35-inch all-terrain tires on factory steel wheels, so we upped the ante with various 37-inch mud-terrains on different aluminum rims. The weight gain and traction didn't help in IFS survival, but it was closer to what we considered the IFS would have to survive if we were going to endorse it. |
Can you hear those OEM engineers clicking their pens and gritting their teeth as we outsmart them? Well, guess what, it's not their fault. We've met many of those guys and have heard, from their smartest engineer minds, that they don't see a problem with cutting all that stuff out and swinging something solid underneath. Heck, they would do it if the job given to them was to come up with a suspension that can take the abuse. It's just that their job is to sell trucks, not build trucks to take wheeling over rocks the size of Yugos while spinning 40-plus-inch-tall tires with V-8s at redline. That's too bad because we'd love to apply the OEM's millions of dollars and brainiest of brainpower to building a truck with an unbreakable front axle, either solid or independent. (On that note, let's all tip our hats to the Ford Super Dutys, Dodge 3/4- and 1-tons, and righteous Jeep Wranglers that haven't been lost to the dark side. May those engineers and product coordinators all take a bow for their solid stand against feebly wobbliness).
We then decided the Sled should...
We then decided the Sled should be able to do a maneuver known as a front dig made popular by the rockcrawling competitors. This is done with a transfer case that offers front-wheel-drive-only in low range. Simply put it in front-wheel-drive-only, crank the wheel, and stand on the brakes; the front end drives through the brakes and drags the truck into a tight circle. This is commonly used off-road for tight trails, but it is also a great test of the front axle. We opted for a STaK Monster Box three-speed transfer case that offers both 3:1 and 5:1 low ranges and front-wheel driveability.
Over the past year we have tried to address the independent front suspension under our '91 3/4-ton Chevy, commonly referred to as the Red Sled (because it's long and turns like a toboggan). We have lifted and locked the truck, added gears and a transfer case that would allow for front-wheel-drive-only maneuvers, and gone through a plethora of different halfshafts. And to what end? We have come to a point where wheeling the truck isn't possible, at least if we want to wheel for more than five minutes. The truck is practically allergic to dirt. It's too bad because we had dreams of building the "be all, end all in IFS," but it was more like "be expensive and broken" after every trip to the dirt. The fact is we could have gone further, but we didn't.
However, we hope you will, and by "you" we mean that one guy somewhere in his shed with more free time and money than us. Or maybe that one engineer who is too stubborn to let us badmouth his beloved IFS, because we truly do want to see one that will work. And by "work" we mean take a 7,000-pound truck with a big-block running torque through a 5:1 transfer case, and send all the power down the front driveshaft where only a set of halfshafts attached to a locked centersection spinning some 37-inch or larger tires can drag the rest of the behemoth over rocks the size of those cute Mini Cooper commuter cars. Build the monster of all IFS and let us know how you did it, but until then this is how far we got and some options if you're ready to cut the A-arms off and swing something stronger underneath.