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Project Red Sled 1991 Chevy Truck - The Sled Is Dead

Removing IFS Like The Plague

Photography by Off Road Unlimited, The 4-Wheel & Off-Road Staff

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 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.
    The Red Sled has been through some arduous testing, but it rarely made it longer than five
  • 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.
    A few weeks later we took it on an easy run on a muddy trail, but that also resulted in a
  • 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.
    After a few more tests that resulted similarly, we upgraded to a set of Rough Country half

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 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.
    We took the Sled for another alignment at this point. The many parts of the IFS were not h
  • 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.
    One of those early trips resulted in the rear driveshaft getting twisted like a pretzel, s
  • 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.
    We had been running 35-inch all-terrain tires on factory steel wheels, so we upped the ant

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 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.
We then decided the Sled should be able to do a maneuver known as a front dig made popular

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.

  • One other upgrade we did was the addition of a ram assist to the steering and some beefier tie rods from Blitzkrieg Motorsports. This gave the truck the power to easily turn the big tires and also replaces the miniscule tie-rod ends with big Heim joints and chromoly tubing. We removed the sway bar too at this point to see what affect it would have on performance and found no major downfalls on road, but slightly more wheel travel off.
    One other upgrade we did was the addition of a ram assist to the steering and some beefier
  • With the added traction of some big mud tires and the low gearing of the STaK, we felt we were finally ready to hit some rocks. The steering was ready to weave through the boulders and we had some aftermarket halfshafts which should be stronger than factory. From the moment we dropped into low range it was like a bomb ticking away, and at the fabled five-minute mark the fuse ran out with a bang.
    With the added traction of some big mud tires and the low gearing of the STaK, we felt we
  • Once again we had a busted passenger-side halfshaft. It seems there was a groove for a snap ring in the Rough Country halfshafts and it was the perfect stress riser where a break quickly started. We were soon fixing the old Sled along the trail. We must admit that we could now change a halfshaft in under 20 minutes and without needing to jack up the truck or pull the tire. Unfortunately, fixin' ain't wheeling and we parked the Sled that day and rode with the other guys.
    Once again we had a busted passenger-side halfshaft. It seems there was a groove for a sna
  • Then we came across the ultimate in halfshafts. RCV Performance built us a set of halfshafts with chromoly inner shafts and size-30 inner CVs similar to those used by high-horsepower sand rails. Meanwhile the outer CV is on par with the massive CVs offered for Dana 60 1-ton axles. We were looking at roughly $1,800 per halfshaft, but these are the same as those found in many of the champion off-road race trucks, so we figured they would be more than adequate for our trail tank.
    Then we came across the ultimate in halfshafts. RCV Performance built us a set of halfshaf
  • The biggest issue with these monsters was the assembly and installation. It took a few hours to get one installed, but we were sure to get them securely tightened as well as properly greased and the proper clamps over the massive CV boots. We had determined that the passenger-side axle needed to be an inch longer than the driver-side since the suspension hangs the differential off to the driver side slightly. But once the halfshaft was installed we were excited to finally go abuse our guinea pig.
    The biggest issue with these monsters was the assembly and installation. It took a few hou
  • However, at this point some other issues arose. Due to some underhood work, we had the front ARB Air Locker disconnected, and a time shortage meant we didn't get the second RCV halfshaft installed on the driver side. We were going off half-cocked for sure, but with all the previous testing having been done with a stock driver-side halfshaft, which we never broke, we felt we could go wheeling and hopefully see better results. Thus we headed up for a day of wheeling with the cronies and eagerly dropped the Sled into low range.
    However, at this point some other issues arose. Due to some underhood work, we had the fro

We should have known better, but we thought we would try the elusive front dig. All was going great as the big behemoth was crawling around and we felt the IFS might actually live, so we headed for some rocks. Now remember that this was with the front diff unlocked, and after the front-dig maneuver, which worked but made some bad noises, we shifted back into four-wheel drive. We crawled into the rocks, which were more basketball-size than Yugo-size, and heard some silly poppin' and banging up front. We crawled out to check it out, and both halfshafts looked fine, both the high-dollar RCV passenger-side and the original driver-side stock version. But then we noticed the front aluminum housing was blown in two and dribbling gear lube, and the time on our watch was just five minutes since low range was engaged.

What Next?

Of course ORU has also been working on a solid-axle kit for other trucks, and its shackle-reversal kit for Ford trucks would be a good start if you wanted to turn a TTB truck into a solid wheeler.
Of course ORU has also been working on a solid-axle kit for other trucks, and its shackle-

So where does this leave us on the Sled? We could go to the next level and build some sort of custom centersection out of steel or iron, but we already sank over $3,000 into axleshafts and custom steering. And then what about the A-arms and steering knuckles. Should we go and have those all fabricated la trophy-truck style? Or maybe we could find a set of the portal box knuckles used in Hummer H1s and work them into the mix, making for a strong suspension that reduced the abuse on the halfshafts and everything else upstream. However, the fact is we've spent so much time trying to go wheeling with this truck and not making it very far that we are ready to do something different. We have a great solid front axle in the wings, but we may just pull the rest of the drivetrain and stuff it all in something smaller and more nimble since the 153-inch wheelbase hasn't revealed itself as the winning wheelbase for our narrow local trails. The fact is that our IFS testing resulted in way too many wasted Saturdays when we wanted to be wheeling rather than wrenching. Days we'll never get back, mind you. That is reason enough for us to steer clear of the independent stuff and take the next step to a solid new beginning.

  • If we keep the Sled and build off of it we'll probably look into the Off Road Unlimited solid-axle swap kit for the '88-'98 trucks. These use tried-and-true leaf springs and are designed for use with a Ford high-pinion front axle like a Dana 60 from a '79 1-ton.
    If we keep the Sled and build off of it we'll probably look into the Off Road Unlimited so
  • If money is no object, then why not start with a brand-new two-wheel-drive Chevy and swing a divorced Atlas and Dana 60 underneath to make the solid-axle 3/4-ton that the GM engineers never got to design? ORU's latest kit uses links and coilover shocks and offers a ride on par with any IFS suspension, yet none of the weak points.
    If money is no object, then why not start with a brand-new two-wheel-drive Chevy and swing
  • Not everyone is starting with a fullsize GM truck. A shop in Detroit known as Diversified Creations is in the final stages of designing a great budget solid-axle swap for S-10 Blazers and pickups that will utilize a Jeep Wrangler front axle or any aftermarket axle with the appropriate Wrangler TJ bracketry. You could easily build an S-10 into as extreme a wheeler as you desire.
    Not everyone is starting with a fullsize GM truck. A shop in Detroit known as Diversified
SOURCES
Diversified Creations
www.diversifiedcreations.com
ARB
2-06/-264-1669
www.arbusa.com
Tuff Country Suspensions
www.tuffcountry.com
Off Road Unlimited
www.offroadunlimited.com
Blitzkrieg Motorsports
www.blitzkriegoffroad.com
RCV Performance
815-877-7473
www.rcvperformance.com
STAK 4x4 Rough Country
www.roughcountry.com
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