The Thuren Fabrication 2014 to current Ram 2500 and Power Wagon rear 4 link kit replaces the factory rear arms and mounts to dramatically reduce axle wrap, wheel hop and improve rear suspension function with new rear control arms and mounting points.
The main purpose of this 4-Link Upgrade kit, was to address the horrible OEM design rear 4-link geometry on these trucks, which leads to massive axle wrap in soft terrain or snow. What makes the OEM design so terrible, is basically 3 specific details. These details are lack of upper and lower arm separation, very soft high-deflection bushings used, and very bad Anti-Squat geometry. The Thuren 4-link upgrade kit fixes all 3 of those very critical details. To go into more detail, the first two noted points make it so that the axle housing is allowed to rotate under load, very much like leaf springs do, storing and releasing undamped energy as axle wrap shudder, when the tire looses grip. The very low Anti-Squat Instant Center makes it so that under drive power, the tires actually want to lift away from the ground. The opposite of what you want! What all this amounts to is a design that promotes terrible axle wrap shudder under forward drive loads.
One other aspect Thuren has improved is the ride quality and vertical travel. This is accomplished by removing the OEM arms which use Torsion Bushings, which store energy like a spring. The 8 of these OEM Torsion Bushings take quite a bit of force to allow the axle to move 6" up and down. With them now being gone, you have effectively lowered the spring rate. If you tow or load heavy often, this could be undesirable, as you will notice a bit more sag when weighted as you have lost some of that "Torsion Bushing Spring Rate." If you tow heavily and want to use this kit, we recommend pairing it with Timbren or Sumospring bump stops or this Full Travel airbag kit.
Fitment:
Fits 2014-2024 Ram 2500 and Power Wagon
Functions with stock coils/shocks and all shock and coil spring options from Carli/Thuren but does NOT work with Carli 3.0 Dominator rear shocks.
Details:
Eliminates Axle-Wrap shudder**.
Relocation brackets have integrated skid plates.
Uses our proven Greaseable Control Arm Joints.
Raises Anti-Squat Instant Center.
Improves ride quality and available suspension travel.
12/8/23.... We're finally releasing this first stage of our Ram 2500 and Power Wagon rear 4-Link upgrade! The second release full Predator Rear Kit will come soon. More notes on that below***.
** Regarding the Axle wrap Shudder: Now that our kit has raised the Anti-Squat Instant Center, when driving forward the rear tire is virtually pushed harder into the ground, for better hook up. The opposite to that is that under load when in reverse, now the tire is lifting under load. What this means is that while we have virtually eliminated axle wrap shudder moving forward, shudder could be the same or maybe even a little bit worse than stock when in reverse, in soft sand or snow. For most of us when in those conditions you are in 4 Wheel Drive, which makes it not a concern as the front axle is doing most of the work, but we wanted to be sure to note this detail.
*** Notes on the future rear Predator System: Our Rear Predator System is to be released for purchase Jan 2024, and planned to be shipping a month or two after that. It will have all the same benefits as this product does, and more. It will consist of a different Machined 7075 Aluminum lower arm, King 3.0 3-Tube Bypass shocks, extra misc mounting brackets, limiting straps, etc. Planned full rear kit price for the noted is about $7000. Maybe a bit more. You will be able to upgrade to the Predator Rear kit from this 4-Link Upgrade kit, but you will have left over lower arms that we will not take back on trade in. In other words, if you are planning on eventually doing with the full Rear Predator System, you are better off waiting on that as if you go to it as an upgrade from this kit, you will be spending about $600 more in the end, and you will have left over lower tubular arms.
