Rams equipped with the 5-link rear suspension offer an unparalleled on and off-road ride quality in both factory, and modified form. Straight off the dealer lot, the small bump compliance and composure of the factory suspension is reminiscent of driving a 1/2-ton. That said, this suspension design comes with its share of downfalls. The one were addressing with the Carli Extended Rear Track Bar is, as the name would imply, the length of the factory track bar.The suspension is designed with 4 trailing arms maintaining the rear axles vertical, fore, and aft movement while the lateral axle movement is controlled by a track bar. This track bar attaches to the frame on the passenger side and axle on the drivers side. This opposes the front track bar thats mounted to the frame on the drivers side and axle on the passengers side. These opposing track bar mounting provisions cause the chassis to twist over the axles as the suspension cycles through its travel. When the truck is suspended on a rack, springs removed its easy to see how the axle shift side to side as they travel through the shock stroke. In the real world, the tires are planted on the pavement (or dirt); their traction means the body shifts as the suspension cycles. This body movement (rotation of the vehicle around its vertical axis) is referred to as yaw. The more linear the axles path through the travel stroke, the less yaw will be encountered.There are two ways to mitigate the lateral movement of an axle with a track bar. First, lengthen the bar itself. The lateral movement thats felt, in cab, is the effective shortening of the track bar. The track bar will pivot around its fixed mounting hardware. The frame bolt is static; the track bar is at its longest when its perfectly flat. Its shortest when at its most extreme angle. The effective length and drastic angle change through travel is whats felt as in-cab yaw. Extending the length of bar itself, spacing the pivots further away from each other, will lessen the effective length AND angle change through the same stroke of travel.With the bar as long as possible, flattening it at its center-point in travel (ride-height) will present the least deviation from its longest to its shortest effective length. Most miles are spent on the highway or around town; even light offroad. For this driving, the suspension will live in the middle 50% of its travel. Its within this middle 50% that the side to side movement of the rear axle should be the least. To accomplish this, we designed the longest bar on the market a whopping 13.8 longer than the factory bar then lifted the axle end and lowered the frame end to ensure the bar pivots were level at ride height. The result is a track bar that effectively disappears in the rear. Theres no detectable rear yaw on a truck with the Carli Rear track bar. In analyzing the extremes of travel, youll see the most deviation given the amount of movement in the suspension when encountering obstacles large enough to reach these travel extremes, the lateral shift was still undetectable and, at its most, the Carli track bar saw 5/8 of shortening.Last important metric Roll Center. This concept is not easily understood; luckily, there is a ton of literature online should one want to study the concept. In short, the roll center is the center-point (axis) around which your vehicle rolls. This roll center exists independently in the front and rear track bars. These two are connected by the roll-axis, but were not going to get that nerdy, here.As were talking about the rear, specifically, thats what well address here. Ideally, the roll center will each align with the center-line of the vehicles mass. This ensures