Questions About Shocks/Springs Ram 2500

[jonathon]

I think the part number issue is one of laziness with Ram. If you search by VIN the correct coils for your application will pop up even though they say fits multiple trims. The Power Wagon coil part number is unique to the Power Wagon, it’s just not listed as such.

I have Thuren’s 2” coils and Fox 2.0 shocks on the front of my 2019 Hemi 2500. Rides great in the front. The stock rear frustrates me a bit. It’s not harsh but certain road features tend to make the truck feel like the rear is bouncing. I’m running 45 PSI on an empty truck. Drove a leaf sprung F350 and on those same roads it was smooth, of course it sucked going over pot holes.

I am tempted to try Thuren’s Fox 2.0 shocks for the rear and see if that helps. Next step would be a track bar. Core 4x4 makes control arms for these trucks and that may help too.

I am hesitant to try Thuren’s 1” rear coils. I do not haul or tow a lot, but do load the truck up for trips.

 

[2manyprojects]

Wildpeak, thanks for posting the link to that Mike Cairns interview. I started my career engineering in the auto industry, and still enjoy hearing from the people that actually designed and brought the product to market. Interesting reference to the "power-hop shock", and how it was needed to help the torque of the Cummins. I'm only aware of it on the gasser Power Wagon now. I'm guessing electronic torque control and better rear spring /shock tuning enabled them to delete from more models.

Without getting off topic, is there something unique about the rear control arms on the Power Wagon? I see some references to an "articulink" lower rear arm in some parts lists, but have only ever seen discussion about the front radius arms.

 

[2manyprojects]

I think the part number issue is one of laziness with Ram. If you search by VIN the correct coils for your application will pop up even though they say fits multiple trims. The Power Wagon coil part number is unique to the Power Wagon, it’s just not listed as such.

I have Thuren’s 2” coils and Fox 2.0 shocks on the front of my 2019 Hemi 2500. Rides great in the front. The stock rear frustrates me a bit. It’s not harsh but certain road features tend to make the truck feel like the rear is bouncing. I’m running 45 PSI on an empty truck. Drove a leaf sprung F350 and on those same roads it was smooth, of course it sucked going over pot holes.

I am tempted to try Thuren’s Fox 2.0 shocks for the rear and see if that helps. Next step would be a track bar. Core 4x4 makes control arms for these trucks and that may help too.

I am hesitant to try Thuren’s 1” rear coils. I do not haul or tow a lot, but do load the truck up for trips.

Agreed, I like to think that the model references are saying that the specific part may be used, but it doesn't help in part/model tracking. The vin# works, but is tedious.

While I don't have any direct experience with the RAM yet, I've always replaced all 4 shocks when modifying on the premise that they are developed as a "system" and you get maximum benefit/performance overall. OEM shocks often wear out fairly quickly, also.

I tried to look at Core 4x4's website; I see reference to RAM control arms, but couldn't access any specific info or prices. I'm guessing custom lengths, materials, and "johnny joints"?

 

[WILDPEAK]

Wildpeak, thanks for posting the link to that Mike Cairns interview. I started my career engineering in the auto industry, and still enjoy hearing from the people that actually designed and brought the product to market. Interesting reference to the "power-hop shock", and how it was needed to help the torque of the Cummins. I'm only aware of it on the gasser Power Wagon now. I'm guessing electronic torque control and better rear spring /shock tuning enabled them to delete from more models.

Without getting off topic, is there something unique about the rear control arms on the Power Wagon? I see some references to an "articulink" lower rear arm in some parts lists, but have only ever seen discussion about the front radius arms.

@2manyprojects Yea I saw that info about the power-hop, I thought that was power-wagon only thing but I suppose it was used on other earlier models.

Regarding the rear suspension of the power wagon, it's basically identical to the 5-link non-PW 2500 (except with the softer coils). There's nothing "articulink" about the rear, only the front radius arms are "articulink"...and they work quite well.

 

[jonathon]

Agreed, I like to think that the model references are saying that the specific part may be used, but it doesn't help in part/model tracking. The vin# works, but is tedious.

While I don't have any direct experience with the RAM yet, I've always replaced all 4 shocks when modifying on the premise that they are developed as a "system" and you get maximum benefit/performance overall. OEM shocks often wear out fairly quickly, also.

I tried to look at Core 4x4's website; I see reference to RAM control arms, but couldn't access any specific info or prices. I'm guessing custom lengths, materials, and "johnny joints"?

I think my first change to the rear is going to be shocks and a track bar. Thuren claims their track bar resolves the issue I have which seems to be contained to concrete freeway slabs and bridges. Truck rides great, especially off pavement.

The Core 4x4 links are popular with the 1500 crowd.

Core 4X4 Heavy-duty Adjustable Control Arms & Aftermarket Parts

CORE 4X4 products are built with high-quality materials right here in the USA and carry our unique “You break it We replace it” lifetime replacement guarantee.

www.core4x4.com

 

[GeorgeHayduke]

@2manyprojects Yea I saw that info about the power-hop, I thought that was power-wagon only thing but I suppose it was used on other earlier models.

My 2016 Ram 2500 has the power hop bracket and extra shock but that's because it's a manual transmission. I believe that year only the power wagons and Cummins with G56 transmissions got it.

 

[2manyprojects]

jonathon, rear shocks and track bar makes a lot of sense, and is partially the reason I decided to go with the AEV kit. Almost universally, aftermarket track bar kits not only replace the bar w/ a longer or adjustable one to re-center the axle, but move the mounting pts to put the bar in a more horizontal position at ride height. There's a lot of discussion on boards about getting rid of the "weird" feeling on pavement over bumps when loaded or towing. It really just allows the axle to move more straight up/down without as much angular shift.

You've probably seen this already, but this gets discussed in the later part of the vid: AEV on RAM suspension

Those Core 4x4 arms look really stout, but I'm not sure I'd gain enough benefit to warrant the investment. If a person was doing a more extreme lift, I could definitely see the adjustable arms being useful to adjust geometry. I'm more concerned about the front axle, and am debating whether to install the PW front radius arms. I don't have illusions that I'm going to do a lot of severe articulation rock crawling, but have seen enough reports of front axle damage to believe they may at least lessen the twisting stress on the axle. I'm waiting for the kit to arrive, and probably overthinking everything while I wait...

 

[2manyprojects]

George, I thought other models besides the PW got the power hop, but it makes sense for the manual trans Cummins with the user being able to drop the clutch as they see fit. I suspect as RAM developed other features like the torque control and refined the suspension, they found they could eliminate it from more models. I've experienced severe wheel hop with my truck already, but attribute it to backing up a grade w/ no load and still having the little OEM "slicks". I thought I was used to diesel torque after driving my Colorado for a few years, but this Cummins is on a different scale... ?

 

[chet6.7]

I think my first change to the rear is going to be shocks and a track bar. Thuren claims their track bar resolves the issue I have which seems to be contained to concrete freeway slabs and bridges. Truck rides great, especially off pavement.

The Thuren bar does what he claims.you won't be sorry.This is a good thread,I would like to add a heavier stock spring rate to the rear of my truck because of the constant load,just to get rid of some sag. Ram is very lazy in their parts book,as lazy as the parts guy at my local dealer.I suspect he is surfing porn in the back room ,he doesn't like to interrupted with questions about spring rates.

 

[jadmt]

The Thuren bar does what he claims.you won't be sorry.This is a good thread,I would like to add a heavier stock spring rate to the rear of my truck because of the constant load,just to get rid of some sag. Ram is very lazy in their parts book,as lazy as the parts guy at my local dealer.I suspect he is surfing porn in the back room ,he doesn't like to interrupted with questions about spring rates.

he probably does not have a clue to what a spring rate is. I doubt there are many parts people who have a clue. I went to get a drain plug for my differential cover and the gal parts person looked it up on the computer and came back with a plug for a transfer case. I said no that is not the right plug and she argued with me. I had her show me on the computer what she was looking at and sure enough it was the transfer case. I said no I need a differential cover plug and she said this is the differential cover plug.

 

[WILDPEAK]

@jonathon @chet6.7

I've had zero rear wiggle with the Carli frame drop trackbar bracket, and zero rear wiggle with the AEV axle side raised track bar bracket. If I was to restart or just purchasing parts I would get the Thuren axle side raised rear setup, but I already have the AEV solution which is seemingly fine at this time especially compared to OE.

 

[WILDPEAK]

I've been thinking more and more about the suspension on the late model RAM 2500. An engineer by education, I've even doing some refreshers on basic dynamics and vibrations courses. Without getting too nerdy on over sprung/undersprung and overdamped,underdamped... I've concluded a few things, mostly shortcomings from the factory for how many of us are using these RAM 2500 trucks.

I think the inboard coil design needs a stiffer spring rate than desirable for comfort and speed in order to maintain side to side stability. You can up the swaybar stiffness and up the valve stack on shocks all day but they will just be compromises to either articulation, high speed, or both. Springs inside the frame rails are an issue especially as the COG increases...

You can achieve desired ride height with softer springs like Thuren or Carli or Power Wagon OE springs plus spacers... But you will still not achieve optimal side to side stability plus load without helpers like airbags or Sumos/Timbrens which are positioned out further and provide added side to side chassis stability in addition to load carrying capacity.

You dont see this "sway" discussion on the Tacoma forums, or on Colorado forums, (all with outboard leaf springs); many overload those trucks beyond GVWR just by adding a heavier duty leaf pack to achieve ride height... but us RAM 2500 owners also don't talk about lack of power or lack of brakes or lack of space ...

I can't believe how many RAM 2500 expedition builds are popping up in North America and Australia. Just a quick look at the full-size sub-forum on Expedition Portal reveals quite a few new Power Wagon builds. I think a "performance" suspension that balances load carrying capacity, go-fast ability, highway stability, and off-road articulation catered to the overloaders is looking more and more financially feasible for the aftermarket...

 

[2manyprojects]

Wildpeak, I share your engineering affliction and many of your views, but believe some basic physics and the inherent compromises desired for overlanding force limits on suspensions. While the Ram 2500 coils-inside-the-frame may be inferior for lateral stability, don't forget Ram is the only mfr I'm aware of that has embraced rear coils for HD trucks. Coils offer a lot of functional advantages over leaf designs , but are more complex and potentially less durable. I think the large payloads we desire for overlanding exceed the "acceptable" range any current suspension tech can provide.

A stock Ram 2500 will fit 35" tires no issues, and carries the 10K GVWR. Move to the PW, you lift about 2", reduce GVWR to 8565, and gain significant articulation. Pretty much same tire fitment, so actual ground clearance is pretty equal. The added articulation is good off-road, but a detriment on-road, in that if you are at or exceed max payload your on-road stability is compromised. Basically higher COG and heavier loads require more stiffness and damping. Not picking on the PW (love the benefits of the lockers and sway disconnect) but the suspension design and lift really alter the on-road loaded stability. The Colorado ZR-2 has similar issues for similar reasons. What's needed is a truly wide range adjustable spring / damper system which can compensate for the large (and higher) payload range, while still keep the soft bottom range.

For springs, the only tech I'm aware of currently that does this is air and maybe progressive rate coils. both have design issues and/or durability challenges for overlanding. Instead we wind up picking how we want to balance off-road articulation, load carrying capacity, and on-road stability. My view, the tech doesn't exist to truly do what we desire, so we're forced to pick a balance and give something up. I'd love to see more RTI testing with fully loaded vehicles; most numbers I see are empty vehicles where softer springs dominate and you seldom see a suspension touch it's bumpstops.

I would very much like to see the aftermarket offer coil springs (progressive?) that are higher rates / load carrying than current offerings. I also question how "bad" the stock (non PW) springs are, especially if you're at the upper end of the rated payload, and whether longer travel designs can be can be done which provide a real benefit. If we assume the OEM has designed the OEM springs to function acceptably at the max load, how much "window" is there for a heavy load/compliant aftermarket spring? No aftermarket will mess with anything that is perceived as enabling someone to exceed their GVWR, but why not springs suited to the upper part of the GVW? OME does this now for the Chevy Colorado, and many other vehicles, but you definitely lose the empty ride when you choose heavier load springs...

 

[WILDPEAK]

Not picking on the PW (love the benefits of the lockers and sway disconnect) but the suspension design and lift really alter the on-road loaded stability.

Appreciate the thought and reply. I pick on the PW suspension all day. Out of the box an OE PW offers a relatively good value considering lockers, swaybar, articulink arms, winch, skids. I would do a Tradesman + PW package if I did it again for an even better value. I just think a lot of folks don't know what they are getting into when they buy one for expedition-style travel with a bunch of weight. The OE RAM 2500 non-PW coils are fine for expedition-style use in my opinion. A pic of the rear mildly loaded with the AEV spacers and the non-PW gas coils below. It's not a rock crawler or the best toy for Moab but there's plenty of flex and articulation for most back country exploring. What lacks is the ability to go fast...

 

[WILDPEAK]

@2manyprojects, what I would like to see is a go-fast suspension designed for 9-10k lbs curb weight, at the upper end of the [non-PW] GVWR, exactly as you pointed out. OME has done this Toyota after Toyota (BP-51).

This dream suspension could not be marketed toward the power-wagon crowd in such a way to encourage overloading because legally the door placard on the PW will be at ~8.5k GVWR, while the normal 2500 will be at 10k lbs.

Once AEV releases the Bilstien "XP Cargo" shock option for the dual sport kit, that has the potential to quiet me down for a bit, at least until the next Carli or Thuren-equipped rig comes barreling past me in the desert!