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2018 Ultimate Adventure Derange Rover, Part 7

Posted in Ultimate Adventure: 2018 on November 12, 2018
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Fault them if you wish for their overcomplicated wiring, engine head gasket issues, axleshaft strength, or any number of other faults, but one area of engineering that Land Rover got pretty close to dead-on right in the 1989 Range Rover Classic is the suspension. The factory coil springs up front support the weight and allow for flex, while radius arms control body roll in the turns and help keep the tires from getting too far into the sheetmetal. A three-link suspension allows the rear axle to do tons of flexy work while affording a cushy ride, even on the roughest of roads and trails. Of course, since we are who we are we couldn’t leave things stock. We had to try to make a few improvements, but the end goal was to keep the theme of the Rover suspension alive and functioning while keeping the rig functional, low, and strong.

With help from the Official Shock & Suspension sponsor of the 2018 Ultimate Adventure Official, Skyjacker Suspensions, we honed the British suspension to a fine edge all while upgrading from the factory axles to Dana’s excellent Ultimate Dana 60s. Up front we enlisted help from our friends at Rob Bonney Fabrication to build custom one-off shock towers and axle brackets. Add that to factory radius arms, and a pair of Skyjacker LeDuc Series front coilover shocks intended for a Jeep JK Wrangler, and the Rover should handle like a dream. Out back our plan is to refit the Rover for some Skyjacker early Bronco 2-inch, progressive-rate front coil springs, Skyjacker M95 monotube shocks, and Skyjacker long-arm rear control arms intended for a JK unlimited. Add in a little at-home fabrication with our Miller Electric TIG welder, a great big uniball for the rear upper wishbone, Land Rover service parts from JC’s British & 4x4, and suspension odds and ends from RuffStuff Specialties, and the axles and suspension are ready to flex.

For steering we leaned on the good folks at West Texas Offroad, Borgeson, and Rare Parts to build a beefy steering system to direct the 38-inch Falkens down the road and trail.

All in all, we couldn’t be happier with the way the Rover’s suspension and steering turned out. It flat-out works on the trail and rides great down the road without leaning too much in the turns or feeling unstable at highway speeds. Just as a Range Rover should. To see how and what we did, follow along.

Reusing the general design of the steering and suspension systems on the Rover helped streamline things. Because of the narrowly spaced framerails and large oil cooler on the Cummins R2.8 Turbo Diesel, we called up our buddy Matt Hodges at West Texas Offroad. We knew the best route was to use a forward sweep steering box that would mount outside the driver-side framerail. That means we’d have to use a box from a Scout, some Ford 4x4s, or a right-hand-drive Land Rover or Jeep. Hodges suggested and then supplied us with a right-hand-drive Jeep JK Wrangler box already tapped for one of West Texas Offroad’s Redneck Ram hydraulic-assist rams. These boxes are rare but still available since Jeep sold RHD JKs to rural postal carriers around the U.S. To mount the box, we redrilled and sleeved the Rover’s framerail right where the factory steering box would have mounted inside the framerail.
The input from the steering box of the Derange Rover is transmitted to the wheels using a drag link and tie-rod from Rare Parts. These steering parts are huge, like bigger than a lot of 1-ton steering parts, and very well engineered.
The Rare Parts steering is intended for a JK Wrangler (like our Ultimate Dana 60 axlehousings) and uses massive forged ends that are threaded to accept different tie-rod end cartages. This makes replacing worn parts easy and also makes it easy to swap tie rods or drag links from the bottom of the knuckle to the top. All you do is remove the cartridge and screw it in from the other side; no need for a whole new steering system.
With the right-hand-drive JK steering box from West Texas Offroad roughly in place and connected to the steering column with Borgeson steering U-joints and a collapsible shaft, we started fabbing up shock mounts for the front of the Derange Rover. We mocked up shock towers for Skyjacker LeDuc series coilovers using cardboard. First step was to remove the factory shock mount and part of the coil mount.
The cardboard shock towers were created from 3/16-inch plate steel by Rob Bonney at Rob Bonney Fabrication. These towers mount to the top of the framerails as well as parts of the factory rover coil buckets. Sleeves and gussets help support the shock, and a bar over the engine will tie together the right and left shock towers to help them resist twisting the framerails as the suspension loads and unloads.
Shock towers
These 1/8-inch steel top plates add strength and serve as a good place to tie the shock towers together.
Since our Range Rover has been around since 1989 we decided that now was a great time to replace suspension wear parts, such as the rubber bushings. For that we called up JC’s British & 4x4 for a set of new factory replacement bushings. The bushings that hold the front radius arms to the frame were cracked and dry-rotted, and we didn’t want them turning to dust on UA 2018. Jeff Corwin at JC’s sent us these rubber replacement control arm bushings as well as a set of aftermarket polyurethane bushings.
Rubber or polyurethane replacement bushings are also available for the axle end of the Rover radius arms. We used our shop press and some steel sleeves to replace these bushings on the Derange Rover. Rubber tends to be a bit suppler but not as strong, while the poly bushings are a bit harsher but can last longer than rubber. For now we are going to stick with the rubber, but we’ll keep an eye on these hardworking parts as the years and miles pass.
Before pressing in the new rubber bushings in the radius arm ends, we used our 4 1/2-inch angle grinder with a flap wheel to open up the U-shaped spaces in which the axletubes will fit. As the suspension cycles the bushings will deflect and the axlehousing will rotate slightly inside these cast U-shaped spaces.
We torched the factory brackets off the Ultimate Dana 60 axlehousings and added some 1/4-inch plate steel brackets cut to our specifications by Rob Bonney Fabrication. These brackets are MIG and TIG welded to the axletubes and cast steel housing respectively. More TIG work with tube and plate to the cast steel using high-nickel rod will help keep the housing together despite the twisting forces the radius arms transfer to the housing. We used track bar parts, rod ends, and brackets from RuffStuff Specialties to locate the axle side-to-side.
We’ve been MIG welding for years, but TIG is still relatively new to us. Fortunately much of the same ideas carry over. One thing that’s different when you’re TIG welding to cast steel is that you should both pre- and post-heat the cast metal with an oxyacetylene torch. You want the metal to be at 400-500 degrees while welding. Heat with a rosebud tip, and check the metal’s temp with a digital temp gun or an old oily glove. When your axle is hot enough, the oil should smoke off the metal instantly and residue should burn off. If the welds and axle cool too quickly, cracks may appear in your welds.
For the rear suspension we designed and had Rob Bonney Fabrication cut these lower control arm mounts. We would have liked to tuck the arms up higher, but with the Ultimate Dana 60 axlehousings being as large as they are, we left them just below the framerails for the suspension antisquat numbers to be where we want them. With a little bit of research we figured out that Skyjacker JK Unlimited lower long arm control arms would be about the same length as the Rover’s factory rear control arms. Also these parts are adjustable and use replaceable and or rebuildable ends; that’s good for when parts wear out. For the axle end of the lower control arm we used a pair of 3-inch, 10-degree axle-mount link brackets.
For the upper rear suspension we decided to reuse a large part of the Rover’s forged upper wishbone. With new rubber bushings on the frame end and a 1 1/4-inch uniball and uniball cup, we were able to build a truss on the rear Ultimate Dana 60 that gives us about 9 inches of up- and downtravel and more than that when the rear axle is flexed. This is the start of our uniball mount and axle truss.
To mount a set of Skyjacker Early Bronco 2-inch-lift progressive-rate springs on the back of the Rover, we had Rob Bonney Fabrication built these custom frame-side spring mounts. The center potato shaped steel plate is 3/8 inch thick and helps locate the spring side-to-side, and that 1/2-inch bolt will hold a tab that will keep the spring in place up/down. For the axle side of the spring (inset) we reused the coil perches that came off the front Ultimate Dana 60. A Delrin JK bumpstop extender and a bolt from Skyjacker will help keep the coil spring located on the lower mount as the suspension cycles.
Custom frame-side spring mounts
With the suspension roughly built we can cycle the suspension front and rear to check for clearances and measure for the Skyjacker M95 monotube rear shocks we will run. We reused the factory Rover rear upper shock mounts and welded on lower shock mounts from RuffStuff Specialities.
This sleeve cut on a lathe is about 0.030 inch longer than the mounting surface of the 1 1/4-inch uniball. That extra length helps when the steel shrinks during welding, allowing the uniball to fit in the pocket more easily when the bolt is out. The sleeve stays in place during all the welding on the truss and housing.
From the factory our Range Rover’s upper wishbone attached to the axle using a huge piece similar to a tie-rod end; it bolted between two forged upper arms. We built this housing to hold the uniball. The whole housing is TIG-welded mild steel. You can also see the brass slug that takes the place of the uniball during welding. You don’t want to ruin the uniball with heat and weld spatter before it ever gets used.
Here is the uniball mount bolted into the Rover’s arms to form the upper rear wishbone. This eliminates the need for a rear track bar, but it means that all the side-to-side load has to go through the uniball. That’s why we are using it instead of the factory tie-rod end or a smallish rod end.
The rest of the rear truss is strengthened with plate steel and some heavy-wall, 1 3/4-inch-diameter DOM tubing. We used cardboard to make plate gussets, and TIG-welded to the housing when necessary.
All in all we spent lots of time with our Miller Electric TIG welder. TIG is a bit more tedious than MIG welding, but it’s cleaner and with practice looks great. It’s not perfect, but hey, with the right tools and a little training, if we can do it you can too!

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