Getting right to it – the factory Ram Coil Bucket offers little support to the isolator and, subsequently, the spring. The lower spring bucket cants forward and inward making for some pretty odd spring pressures additionally to the lack of upper spring support.
Let’s take a look at the Ram Bucket.
You can see a few things, here. There’s a hole next to the “cone” – this is the female receiver for the male index on the isolator itself. Second, the cone is short. VERY Short; much shorter than the isolator it supports. Odd, right?
Picture this… The rubber isolator against the bucket, centered by the “cone”, then the spring sits against the isolator. Everything assembled, the isolator is the ONLY thing being supported by the metal cone. The thick rubber body above the spring seat on the isolator means the coil itself may only overlap the metal support cone in the bucket for 1/4-wind of the spring.
As the suspension moves through its minimal travel range (stock form), this whole assembly remains loaded and the coil spring remains in place as the load is mostly linear and the spring is high rate (stiff) and short travel.
For reference (sacrilegious, i know) let’s take a look at the Super Duty Bucket.
The above Ford bucket is, without argument, a better design. The longer metal cone on the bucket provides support to the entire length of the isolator ensuring it acts only as a “damper”, not a spring retainer as it does on the Ram.
How much of an issue is this in the Ram platform? In short, it’s not… if you keep it stock. Throw in a lighter rate coil spring that’s taller, extended travel and allows the customer to run the truck harder thanks to a larger diameter shock well beyond the capability of Ram factory testing and you’ve revealed a weak-point in the factory design.
The lighter spring will be more volatile; less spring rate means it will deflect deflect more both up and down & side to side. Add to this the extended travel range and you’ll see even more vertical, transverse and fore/aft movement of the spring.
The Ram front end is a 3-link; it has 2 radius arms as the fore/aft linkage and a track bar as the lateral link. The radius arm design has two connection points on the axle and one on the frame.
This Suspension design results in lateral shift of the axle through the travel stroke (track bar) AND significant caster change as the axle tilts forward during down travel and back during up-travel (radius arms). At full compression of the front suspension, the track bar shifts the axle position well toward the passenger side while the radius arms roll the axle back (more caster than ride height). On full extension, the track bar pulls the axle toward the driver side while the radius arms roll the axle significantly forward (less caster than ride height). This caster change effectively rocks the lower spring bucket while the upper remains static. As said earlier, the lower coil seats are angle inward and forward AND our systems extend the travel range.
As you push the boundaries of the stock design, the isolator are the first to tap-out. Ram knows this… Case-in-point, Ram has added more support to the isolator in their platform with taller, lighter rate coil springs and more suspension travel – the Ram Power Wagon.
Ram offers two isolators for the Rams:
- Standard 2500/3500: PN 05168566AB
- Power Wagon: PN 68268825AA
Let’s compare the two. The standard will be pictured on the left, Power Wagon on the right.
The front pictures of both reveal a similar silhouette with different “guts”. When installed, you wouldn’t know what was in. They both have the male locator to index the spring and the a profile is identical. More material can be seen on the inside of the power wagon isolator from this uninstalled view.
Above view reveals more detail to this additional rubber in the Power Wagon Isolator. (Click on the image to view it full-size; i’ve left this image large allowing you to legibly zoom-in on the PN molded into the isolator). You can now see the internal diameter of the isolators is the same at the top, both also having the rubber protrusions/guides to center to the cone, but the Power Wagon isolator has a secondary “Lip”. This molded lip seats to the bottom of the cone on the Ram bucket providing more support as it has more material and surface area than the standard isolator.
From the bottom, the additional material used in the Power Wagon Isolator becomes very apparent. The open, internal diameter of the isolators is 3.875″ vs 3.25″ respectively.
So what’s the solution? Well, there are two and it depends on what you’re doing with the truck. if you’re running one of our leveling systems, the Power-Wagon isolator is a no-frills, easy install that will ensure the coils stays seated. For our 3.25″ Systems, it’s actually less necessary to address the isolator thanks to the provided Radius Arm Drop Brackets. Dropping the Radius Arm Pivot Point from the frame end flattens out the coil bucket minimizing the axle “roll” through the travel stroke that induces most of the unsettling forces to the coil spring.
Regardless, the Power Wagon Isolator is better than the standard in every-way… Unless you plan to party. Enter, the be-all, end all solution; the Carli Spring isolator supports. Disassemble the front end and clean up the cone, insert the Carli Spring Isolator Support, weld, grind, paint and never worry about a slipped coil spring again.
Compatibility Note: As you can see, the Carli weld-in Spring Isolator Support seats to the lip of the cone; this is the SAME lip that the additional rubber on the Power Wagon isolator sits against rendering the two incompatible. If you want to run the Carli Support, you’ll need to ensure you have the standard isolators: PN 05168566AB
Now you’ve seen the two solutions to the factory spring isolator issue. Which is best for YOU will depend on your abilities and application. If i could recommend one solution for everyone, it’s the weld-in support. Both solutions provide more support but the Carli solution offer it in the form of steel which is, obviously, far stronger than the rubber counterpart. That said, it’s the cheaper “part” but the installation will be far more expensive. if you’re capable of welding it yourself, it’s a no brainer.
If you’re running one of our systems up to the Pintop (2.5″ diameter King Shocks), the Power Wagon isolator will be plenty sufficient to offer extra support. The Carli Dominator Systems (3.0″ King Shocks) include the weld-in isolator supports as the capability of these suspension systems is well beyond the support of even the Power-Wagon isolator.
I read this article, had the ability to weld the coil isolators in place and very glad I did! Carli rocks! This upgrade is not hard to do, but will take a little more time to do, but it’s so worth the extra time upfront. I did it and glad I did! No worries of coil springs again… regardless of what suspension system or how hard you push it!
Great info, thank you. Just had my coil slip from my lifted 2500 this morning. Will be upgrading to the PW isolators as a short term fix!