We are nearing the end of our Ultimate Working Heavy Hauler project. In Part Five of the series, we’ll be replacing leaking transmission cooler lines, upgrading the worn steering pieces, and putting some new rubber on the ground wrapped around a set of shiny new wheels. When this build started, the idea was to show readers what the aftermarket had to offer for the true working man. We took a relatively stock 2003 Chevrolet 3500 dually to a whole new level with a host of parts developed to make this thing even better for working and towing. While upping the 01 Factory transmission lines on the Allison-equipped Duramax trucks have been prone to leaks so Deviant Race Parts developed a ½-inch industrial strength hydraulic line kit to replace worn, broken, and leaky stock lines. 40 APRIL I 2017 • DIESEL WORLD www.dieselworldmag.com BY JACOB WHITE W TECH | DIESEL WORLD MAGAZINE horsepower was part of the plan, there was no need to go crazy with it, so the only real power adders came from the addition of custom EFI Live tuning from Duramaxtuner.com. A cold-air intake, 4-inch exhaust, BD Diesel Flowmax lift pump, and Deviant high flow turbo inlet horn were installed as well, but these parts were added with improving overall engine efficiency in mind, rather than power output.


The Bradford Built Workbed and Titan Hammerhead transfer tank and toolbox combo added some versatility to allow the truck to be used more effectively around the ranch this truck lives on. Hauling big hay bales, getting fuel to the combine in the fi eld, and just having a place to store tools for unexpected farm equipment repairs has made these additions basically a necessity. The Road Armor bumper and 16.5 Warn winch have added some sense of security and strength when the conditions get rough, and the extra offroad lighting from the Warn lights installed in the bumper have been a welcomed addition when checking cows in the middle of the night out on the range. Bolting on BD Diesel’s exhaust brake has also been something the owner says he couldn’t live without now that he’s been able to use it while towing heavy loads around. The additional holdback power gives some peace of mind knowing all that weight won’t need to be put on the trucks factory brakes and controlling the truck’s speed, while towing has become effortless and loads safer.

1 Factory transmission lines on the Allison-equipped Duramax trucks have been prone to leaks so Deviant Race Parts developed a ½-inch industrial strength hydraulic line kit to replace worn, broken, and leaky stock lines.
2 This truck has just 69,000 miles on the clock but had already developed a few leaks from the transmission lines underneath the truck, so replacing them before a complete failure of the stock lines happened seemed like a good idea. The new DRP lines include high quality AN and O-ring fi ttings to replace the stock clip-style fittings.
3 The feed and return lines running from the passenger side of the transmission to the cooler mounted behind the grille will be replaced all together. This includes swapping out all the fi ttings on both ends as well. This is a simple job with just basic hand tools required.
4 Disconnecting the factory lines that feed into the side of the radiator where an additional cooler for the transmission fl uid is housed will be required as well. This may entail that you remove the airbox to gain access and give you room to turn wrenches.
5 The new AN fi ttings thread directly into the radiator, these use a special double O-ring seal to guarantee a leak free installation for thousands of miles. DRP is so confi dent in their cooler line kit, they offer a full lifetime warranty.
6 The new hydraulic hoses thread together using the supplied fi ttings and 90-degree adapters at the transmission to make for an easy, kink-free installation. Removing the stock lines from the truck will be the hardest part of this job, but we were able to complete the task in less than two hours start to fi nish, which included topping off the transmission after losing a little on the ground.


The factory GM Allison transmission lines have been known to leak after racking up thousands of miles of on and off-road abuse, and this fairly low-mileage truck was no different. Leaks were developing at the cooler so it was a good time to make a change. Deviant Race Parts of Hayden, Idaho, developed their own resolution with a complete replacement performance hose kit for the 2001-2010 model years. Using your choice of either ½-inch or 5/8-inch extremely heavy duty 1,500psi hydraulic hose and the required fittings to connect your Allison to the factory cooler, leaks can be a thing of the past. Using quality ANstyle fittings with double O-ring and washer-style junctions, once installed and secured your stock or built Allison can keep moving your truck down the road worry free. The conversion is straightforward and can be done in just a couple hours depending on your skill level; just be prepared to fight getting the factory lines out, as they are laced through the chassis and will take some maneuvering to remove.


Since the GM steering design used under these 2500HD and 3500 trucks has been prone to premature wear and slop, something this 69,000-mile truck was already experiencing, a few upgrades were in order. The Rare Parts steering pitman, idler, and tie-rods from Alligator Performance offer an unmatched durability and performance due to their increased sized and improved design. The Pitman and Idler Arms are constructed of a cold-headed hardened and annealed 4140 30mm full ball stud to eliminate binding and provide extreme wear resistance. The arm itself is larger in size as well as forged and heat treated for maximum strength. The grease fitting is also relocated for easier service access.

7 The GM independent front suspension and steering system has always been known for its excellent ride quality and good turning radius, but the idler and pitman arm design is far from durable. The steering setup under the 2500HD and 3500 trucks is by far one of the most prominent failure points, so the crew at Rare Parts Steering developed stronger more durable replacement parts to directly replace the stock pieces.
8 Supplied by Alligator Performance, the Rare Parts tie-rods (top) are placed next to the stock tie rods (bottom) which had previously been upgraded with an aftermarket sleeve for strength. Unfortunately, sleeves only increase their strength from breaking, whereas the Rare Part tie rod improves upon the rod end design for a longer life and better overall strength as well.
9 The factory pitman arm on this truck was quite stubborn and required a cutoff wheel to be used to cut a slice across the outer shell to break its tight hold on the steering box sector shaft. Obviously, extreme care had to be taken here as damaging the splines on the sector shaft means an expensive steering box would need to be purchased.

The OEM tie-rods have always seemed a little undersized for the application and that’s proven by the hundreds of stories we hear from owners experiencing failures in 4×4 situations that put enough load and bind on the front end to snap the tie-rod shaft, leaving you stranded. The aftermarket has helped solve some of this by offering an inexpensive tie rod sleeve, which this truck already had installed. But the sleeves do nothing to increase the durability of the factory tie-rod end. Wear and excessive play in the tie-rod end meant a replacement was needed here as well. The Rare Parts extreme duty tie rod has a massive 1.5-inch rod end forging for unmatched strength. Like the pitman and idler arms, they are also heat treated and use a full ball stud design for durability.

10 To make the swap of the idler arm a little easier, we opted to remove the complete center link and idler arm assembly from the truck as a unit. This allowed us to use an air impact on the idler arm nut and reinstall it to the idler bracket.
11 The factory idler arm (top) and new Rare Parts idler (bottom) sitting next to each other allows you to see just how massive these new pieces are. The improved design will hold up much better to big off-road tires and thousands and thousands of road miles without worry. The OEM parts were already showing significant wear and play with only 69,000 miles on them.
12 The massive Rare Parts tie rod kills two birds with one stone; not only will you replace the weak small diameter tie rod and alleviate concerns of breaking one in 4×4 situations, the heavy-duty rod ends will last much longer.

While these parts are all beefier than the stock parts, they are all direct replacements with no modifications required for installaion. Alligator Performance suggests this steering kit as an end-all cure-all to the GM steering problems and has had nothing but excellent feedback from their customers concerning longevity and strength.


AT2 For traction, this big heavy dually was going to need a tire that could not only perform well on the highway while handling extremely heavy loads, but it needed to be able to keep the truck moving in some nasty mud and snow conditions. The General Grabber AT2 offers the ultimate in versatility due to its innovative tread design with 5-row tread pattern with double v-shaped lugs. This design promotes off-road traction while offering increased tread life and is acoustically engineered for a quiet ride on the highway. Since this truck would be needed around the ranch during the winter months, the Grabber AT2 also offers incredible snow and ice performance with their ability to be studded should you need it. For this build, a 235/85R16 was chosen as it was a little taller than stock but still narrow enough to fit in the rear dual position without rubbing each other on the inside. We opted for the Load Range E of course, to handle the heavy towing weight and this tire comes with a 60,000-mile trade wear warranty.

13 Since the steel cords showing through on the trucks current tires weren’t doing much for traction around the ranch, some new tires were in order and the General Grabber AT2 were just the ticket. While we were at it, we decided the wheels could be improved as well, so a set of new 16×7 Ultra Predator black-and-machined dually wheels were ordered up to be balanced with the new tires.
14 The Grabber AT2 offers a perfect mix of highway performance with enough bite for great mud and snow traction in the ever-changing climates and conditions this truck will be subjected to. The 235/85R16 size was used for this build due to its narrower width and heavy Load Range E rating, it’s perfect for a dually application. The AT2 also allows the installation of snow studs should you need it for the ultimate in winter performance.


Since the truck had already been upgraded with the custom black powdercoated Road Armor bumper and Bradford Built work bed, it seemed only logical to upgrade those boring gray steel wheels with something a little nicer when the tires were going on. Ultra Motorsports’ latest dually Predator wheel was exactly what the doctor ordered. They’re offered in both 16” and 17” diameters; we went with the standard 16×6 in a gloss black and machined design. The new Ultra Predator really took the cosmetics of this work truck over the top. It no longer looks like a generic farm truck; it now has a style and an aggressiveness to it that really works well with the black and white color scheme.

15 With the wheels and tires mounted, this work truck has a much more
aggressive look and much-improved performance on and off the highway.
The tread pattern has proven to work well in the mud while keeping road
noise down when towing heavy on paved roads. The self-cleaning pattern
and sidewall work great around the farm and ranch, and best of all General
offers them with a 60,000-mile warranty.
16 This build has turned into quite the tow rig and work truck. The addition of the Bradford Built work bed and Titan Hammerhead transfer tank have added great versatility, while the performance upgrades like the Duramaxtuner.com ECM and TCM tunes make it a dream to drive. The BD Diesel exhaust brake really helps control those heavy loads as well.

Part Six of this build planned for next month’s issue will wrap this project up. We’ll be bolting on some rear airbags and a sway bar kit from Hellwig along with a new brake controller and a hitch from Curt Manufacturing. These are all parts that will take the truck’s stability and overall towing performance just one step further. It’s all part of the plan in building the Ultimate Working Heavy Hauler.DW


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