What It Takes To Reliably Turn Big Tires - Steering You Straight

What It Takes To Reliably Turn Big Tires - Steering You Straight Harry Wagner Contributor

If you have been paying attention, you know that here at 4-Wheel & Off-Road we like big tires. A lot. Our trucks don’t always like them as much as we do though, particularly the front end components. Dodge/Ram Heavy Duty trucks are notorious for wearing out suspension and steering parts, which can lead to the dreaded “death wobble,” where the entire truck starts shaking violently. We didn’t want that to happen with our new 37-inch Pro Comp Xtreme MT2 tires, so we worked with Offroad Power Products on a game plan to ensure that our ’06 Megacab could handle whatever situation we put it in. In this case, fitting the tires was the easy part. Making the truck live with the bigger tires was another story.

Pro Comp Xtreme Mt2 Tire Photo 81099107 We love our 37-inch Pro Comp Xtreme MT2s. They can carry up to 3525 pounds each and come with a 40,000-mile tread wear warranty. They also weigh 83 pounds each, 66 percent more than the stock tires.

Worn-Out Bearings
Problem: The knuckles on late-model 3⁄4- and 1-ton trucks use a one-piece unit bearing that cannot be greased or maintained, and the bearings are close together, which subjects them to high radial loads.

Symptoms: To check for bearing wear, lift one corner of the vehicle and grab the tire at the 3 and 9 o’clock positions while someone holds the steering wheel to keep it from turning. Rock the tire back and forth looking for any sign of movement.

Our Solution: We ordered up new Timken unit bearings from Rock Auto. The unit bearings came complete with wheel studs and ABS lines, resulting in an easy installation. The unit bearings are not left-right specific either, and with the low cost from Rock Auto we were able to afford a third unit bearing that we keep in our truck as a spare.

Alternate Solution: Dynatrac’s Free Spin Kit replaces the unit bearings with a fixed spindle, serviceable bearings, 35-spline stub shafts, and manual hubs. This kit is significantly more expensive than replacing the unit bearings, but it also results in improved mileage. The Free Spin Kit stops the front driveline from rotating when the hubs are not locked. The CV on the front driveline of Ram trucks has been known to seize up on trucks with over 100,000 miles on them, often taking out the transfer case in the process.

Unit Bearing And Free Spin Kit Photo 81099116

Ball Joints
Problem: Ball joints are one of the most critical components of any steering and suspension system. They act as the pivot between the steering knuckles and are subjected to enormous loads, particularly when larger, heavier tires and wheels with less backspacing are installed.

Symptoms: Loose or worn ball joints can cause poor handling. They can be checked by grasping the wheel at the 12 and 6 o’clock positions and checking for movement.

Our Solution: We ordered Moog offset ball joints from Rock Auto. These high-quality joints allow us to add back some of the caster lost when we previously installed lift coils. They are greasable, strong, and very affordable from Rock Auto.

Alternate Solution: Dynatrac produces ball joints from heat-treated billet steel that are not only stronger than stock but also rebuildable. The Dynatrac ball joints are not offset, but adjustable control arms, such as those available from BD Diesel, offer a wider range of adjustment than our offset ball joints to fine-tune the caster angle.

PhotosView Slideshow ball joint Most parts stores will rent you a ball joint press to remove and install ball joints. We used plenty of antiseize on the new components to ensure that they would be easy to service in the future.

Bent Axles
Problem: The Cummins engine can propel Ram trucks to amazing speeds, but they were never meant to fly. The engine weighs approximately 1,100 pounds, which to put it in perspective is more than double the weight of an aluminum V-8 engine.

Symptoms: Once the axle is bent it tends to take out other components in short order. Bent front axles can result in steering wander, abnormal tire wear, and leaking axle seals, and are often visible from the front of the vehicle with the tires exhibiting excessive camber.

Our Solution: Artec Industries manufactures axle trusses for a wide variety of applications, from JK Wranglers to Ford 8.8 axles swapped into TJ Wranglers. Artec’s AAM axle truss ties all of the suspension bracketry together and has gussets for the inner knuckles to prevent them from bending.

Alternate Solution: Axletube sleeves are available that provide more ground clearance than the Artec truss but do not address the issues of bending knuckle Cs or tearing suspension brackets off of the axletubes.

PhotosView Slideshow axle truss welded on We were concerned when the Artec truss did not come with any instructions, but the fitment is so precise that it is impossible to get wrong. The truss comes in six pieces for easy shipping and is made from 1⁄4-inch-thick mild steel that is CNC designed and laser cut. Dylan McFarlane welded the Artec truss on for us with his Lincoln 225C MIG welder. He stitch-welded the truss and moved from side to side, taking his time and allowing the weld to cool to prevent the axle from warping.

Steering Box
Problem: Many of the front end issues in Ram trucks are a result of having to survive below the heavy Cummins engine. The steering box is no exception, and the long sector shaft and bearings are subjected to huge forces.

Symptoms: As the bearings in the steering box wear they result in slopping steering and wander. If you have a Cummins-equipped truck make every effort not to turn the tires while the vehicle is at a stop.

Our Solution: BD Diesel offers a steering box brace that essentially captures the sector shaft in double sheer with another attachment point below the pitman arm. The brace spans between the framerails to eliminate frame flex or any unwanted movement in the steering box. This was the easiest product we installed. If you have a Dodge Ram this should be your first upgrade.

Alternate Solution: Diesel Power Products offers an upgraded Mopar steering box with a larger sector shaft and upgraded internals. The BD steering box brace will still work with the Mopar box, although new hardware is required.

PhotosView Slideshow steering linkage steering box brace installed

Worn Tie-Rod Ends
Problem: Ram HD trucks use a steering system in which the drag link connects to the passenger-side knuckle, and then the tie rod connects from the driver-side knuckle to the drag link. The inverted-Y steering allows the tires to scissor inwards and out, causing the steering wheel to turn uncontrollably and the tires to cup.

Symptoms: Worn tie-rod ends result in slop in the steering and are not serviceable. Check for play in the steering system by having someone turn the steering wheel slightly from side to side while you look at each part of the steering system for movement that does not translate into tire movement.

Our Solution: Synergy Manufacturing recently introduced a Dodge steering upgrade with bolt-on installation that is superior to stock in every way. The drag link and tie rod are 200 percent stronger than stock, and the tie-rod ends are both stronger than the factory components and easy to replace, should that ever be necessary.

Alternate Solution: ’09 and later Ram HD trucks came from the factory with inverted-T steering, which uses a tie rod that connects the two steering knuckles together. This is better than the inverted-Y but still not serviceable and not nearly as strong at the Synergy steering.

PhotosView Slideshow The Synergy tie rod is constructed from 11⁄2x0.188-wall chromoly tubing that has been heat treated. the drag link is made from 11⁄2-inch solid stock and uses pinch bolts on the tie-rod adjusters. These are parts you would normally find of a race car, not a tow rig. Synergy Manufacturing uses replaceable left- and right-hand tie-rod ends for its steering system. These tie-rod ends use the same size and taper as stock for bolt-in installation but are stronger than stock, with forged bearing housings fitted with 4140 chromoly tie-rod studs. After installing the new front end components we set the toe with a tape measure and took the truck straight to our local 4Wheel Parts. 4Wheel has the latest Hunter alignment equipment and are accustomed to dealing with big trucks and big tires, unlike some other alignment shops we have been to in the past. Upgraded Components Installed Photo 81099365 The upgrades we made to our Dodge allow us to run our 37-inch Pro Comp Xtreme MT2s with confidence. No matter what sort of punishment we put the truck through, death wobble should never be an issue.