boogielander
Ram Guru
- Joined
- Jun 29, 2022
- Messages
- 1,785
- Reaction score
- 2,533
Parts Used
- Carli Boxed Upper Control Arms: CS-RAM15UCA-09
- Carli Rear Springs, Rebel HD: CS-RAM15MRC-RBL-19-R-HD
- Carli Rear Sway Bar End Links: CS-RAM15-EL-R
- Fox PERFORMANCE ELITE SERIES 2.5 COIL-OVER RESERVOIR SHOCK (PAIR) - ADJUSTABLE - 883-06-166
- PERFORMANCE ELITE SERIES 2.5 RESERVOIR SHOCK (PAIR) - ADJUSTABLE - 883-26-079
Go Cheap vs Go Expensive
I had prior experience with Bilstein 5100s (a popular option for many people), and let me just say those <2.0in diameter shocks are trash for any serious offroad use:- Small shock body
- The bigger the shock body, the more shock fluid stored. More shock fluid means better heat dissipation, a vital part of keeping the shock functional during those fast strokes while going through uneven desert terrains.
- Like many other things on your vehicle, heat is the enemy of your truck's performance. With a <2in diameter, there is simply not enough fluid in the shock body to dissipate the heat and results in cooked shock fluid and broken seals.
- No remote reservoirs
- Remote reservoirs serve the same function as bigger shock body: to hold more fluid for heat dissipation.
- Un-tunable and unserviceable
- These throwaway shocks are sealed from the factory, making them impossible to tune for better offroad handling based on your truck's load.
- The sealed design make them impossible to be serviced, hence I call them "throwaway shocks." You throw them away when they're at the end of their service life
Hence my conclusion: for serious offroad performance, cheap and non-podium winning shocks are trash.
Overview - Why
There are only two options for offroad performance shocks: King 2.5 and Fox 2.5. There is no third option, not even the Fox 2.0 versions.Such a bold statement, some may say, but like my intended audience (aka, people who want to build their trucks to see LOTS of miles on dirt), these are the only two options that are worth spending money on.
Here's why:
- Race Proven (easiest reason):
- Both King and Fox can be found on podium winning offroad race trucks.
- If it's good at winning racing it is good for our application.
- Rebuildable:
- You can rebuild your shocks instead of throwing them away like you do with cheaper shocks (5100s, Fox 2.0, etc)
- Tunable:
- Shock tuning is a very important part of dialing in your shock package for offroad use.
- This is not a must for you to enjoy going through the desert, but will for sure help with ride quality and control.
- In a nutshell, "tuning" is simply adding or removing stacks of shims on the piston inside the shock body to add/ reduce resistance for the piston to move, which affects how the shock and vehicle responds to various obstacles
- You can read more about tuning here
- Adjustable:
- For FOX DSC, you have the ability to adjust your high and low speed compression.
- For King, you only have mid speed (or a combination for high and low speed) compression adjustment.
- Adjusters are important for dialing that perfect ride if your shock package hasn't been tuned.
- It is not THAT important if your shock package has custom valving from professionals like Accutune, Carli, or Thuren.
Why did I go with FOX 2.5 over King?
I had Kings on my 4Runner and I loved them. I was able to go 70MPH on dirt chasing Raptors and felt completely in control; the shock package took the whoops, bumps, and whatnot in the desert gracefully. And those were not custom tuned yet! However, due to the follow reasons, I decided to go with Fox instead.Lead Time Consideration
Lead time was the primary reason I went Fox over king, to be honest. I was going for Carli King package, but after seeing how long the lead time was for Kings I gave up.I ordered my Rebel at the end of June, 2022 and I started to order parts the first week of July. My goal was to get the truck ready by December, 2022 and do a couple test runs in preparation for my Alaska trip in 2023. That way, I have enough time to dial things in and perfect my setup before embarking on a month long journey away from civilization. However, at the time, we were looking at at least 12 months of lead time on King products, so I decided to go with FOX which had a way shorter wait time.
Dual Speed Adjustment vs Single Speed Adjustment
The single speed adjustment found on Kings was decent, but I wanted more as I wanted to be able to fine tune my suspension.Sure, I could slap the DSC resi on the Kings since the fittings are the same and the valving on Fox and King are pretty similar, and we have the tools and know-how on how to disassemble, assemble, and service these shocks. BUT why add extra work for ourselves when I could just get one with dual speed?
Expected Outcomes?
I expect compliant rides when bombing through desert doing 60+MPH without the truck jerking around like I'm trying to tame a wild horse; at the very least, a wild horse can be tamed after fighting it, but a truck on trash suspension cannot and will not be tamed no matter how much effort was put in. In addition, I expect the on road performance to suffer, but offroad ride quality to greatly increase. To be exact, these are the offroad ride qualities I expected with dual speed control:- High speed runs: shocks do what they do, stroking at high rate of speed to dampen out the uneven terrains as I skip through whoops, dips, and jumps to keep a plush ride instead of feeling everything on the trail.
- Slow speed crawling: shocks keep side-to-side tossing to minimum, resulting in a compliant ride while going through bigger rocks, boulders, ledges, and steps.
- You possibly can save on tax but you have to consider your spouse's reaction when you want to do something, go somewhere, or buy something when you're married. You sacrifice individual freedom for tax benefit (and love... if that's your thing).
- You drive a Hemi V8 because it's a glorious engine, but you sacrifice fuel economy.
- You live in People's Republic of Commiefornia for the good(?) weather, but you have to deal with all the progressive BS, pay all kinds of taxes and fees, and get your individual rights taken away because those politicians can't get their butts out their heads. I mean, their heads out of their butts. Either way works.
- You drive a truck with individual front suspension for better on road comfort, but at the same time you sacrifice offroad suspension travel that solid axles offer.
- You put offroad performance shocks on your truck for... offroad performance (duh) therefore, your truck's on road ride quality will be negatively impacted.
Procedures
Installing lift kits can be done by yourself in your garage or driveway, though I strongly suggest you NOT to do it. If you take it to a shop, they should know how to do it.So I will skip the installation part and focus on the procedures to set up the shocks for both on road and offroad use.
- Start with both low speed and high speed adjustment closed and drive around on pavement to feel how the truck performs. To do this, turn the knob toward the "-" direction until you can't turn anymore, then back 1 click and use that as your starting point. This should give you a rather plushy ride while experiencing body roll while cornering. If you like how it rides, leave it at that.
- Increase low speed adjustment to mid (about 4 clicks in), then drive around to feel how to truck performs. This should give you a rather plushy ride still while experiencing limited body roll. If you like how it rides, leave it at that. If you think this is too stiff, then lower the clicks back down (follow the "-" direction) 2 clicks and go from there.
- Increase low speed adjustment to max (about 8 or 9 clicks in, basically turn it so you can't turn anymore then back down to the first click you feel). This should give you a stiffer ride with very limited body roll. If you like how it rides, leave it. If not, start backing down the clicks 2 clicks and go from there.
- Low speed is what you should be changing for on-road performance. If somehow you're still not satisfied with it maxed out, increase high speed 2 clicks (same procedure - turn toward "-" until you can't and go 1 click back, use that as your starting point)
- If you still not satisfied then add 2 clicks at a time until you're happy with it. Again, you shouldn't need to touch high speed for on pavement performance.
- Repeat the same process for high speed, but in the desert or on the trail.
My Settings
These are my settings with my rig, with about 300lb constant load in the bed.- On pavement (initial):
- Front: Low speed maxed out, high speed closed.
- Rear: Low speed maxed out, high speed closed.
- On pavement (current):
- Front: Low speed maxed out, high speed closed.
- Rear: Low speed maxed out, high speed maxed out.
- This is only because I am spending more time offroad than on road and I can sacrifice on road plushiness in the rear, so I don't bother to change it every time I go back on pavement.
- Off pavement:
- Front: Low speed maxed out, high speed maxed out.
- Rear: Low speed maxed out, high speed maxed out.
- As you can see, I am running the same setting for both on and offroad in the rear.
- Front coil-over preload adjustment is the "cheat" way to increase your ride height without doing the math to figure out the correct spring rate.
- It is not a recommended way to increase your ride height due to spring rate concerns, which directly affect your shock's ability to perform as intended.
- I left my adjustment as is from Fox and did not mess with preload adjustment.
I don't want to mess with the preload and ride height, especially before and during the installation process. The higher you lift the less droop you will have. Imagine your shock has a combined travel of 0-10 for this overly simplified scenario:
- Under normal condition, your piston sits at level 5, in the middle. When you shock droops, your piston now goes down to level 3 and hit bump stop at level 1. When you go over an obstacle, your piston now goes up to level 8 and hit bump stop at level 9.
- Now, when you increase preload to create more lift, your piston sits at level 4 lower than in the middle as you extend the shock for higher ride height. When you droop, your piston has less distance to go down before hitting bump stop at level 1. When you go over an obstacle, your piston now has slightly more distance to travel before the spring rate reaches maximum compression and stops your piston from continue to travel and complete the dampening stroke.
- With correct spring rates, the spring will be the one supporting the vehicle weight and push the piston back to its normal, intended position. Usually higher spring rates are needed when you have extra weights in the front, such as winch and/ or bumper. Alternatively, higher rated springs may be needed if your engine block is heavier (think EcoDiesel).
My Verdict
At the time of writing, it has been about 6 months since I installed the suspension package on my truck. Here are my (random) thoughts in bullet points for ease of reading:- Did these meet my expectations? Yes, they did. The shocks were cycling properly and keeping up with my speed during higher speed runs whereas my friends on less performance orientated shocks were questioning their life decisions. On the other hand, while going through obstacles similar to frame-twisters found in most 4x4 practice areas, my side-to-side movement was controlled; there's no tossing around like those with cheaper shocks experienced.
- On pavement performance is better than stock Bilsteins as well; the ride is a lot plushier than stock with proper adjuster settings, and body lean while turning and going through canyon is reduced. Or, maybe I have a higher tolerance to stiff ride because my other car has a stiffer suspension setup and I feel every road imperfection.
- Is it worth the money? For off-the-shelf suspension package without long lead time at the time of ordering, this is the best you could get.
- Would I recommend? If you are in no rush and not in a crunch to finish your build, I'd recommend going Carli King package, just for its custom tuned valving that they've tested numerous times. If you need a set of good offroad performance suspension ASAP, then I'd recommend these Fox as an alternative to Carli King.
- Will I eventually upgrade? I think I will consider custom tuning these shocks when they are due for rebuild. Or I may buy a set of long travel with external bypass if I decide to mess with it. Or, I may even go the Power Wagon route with Carli Dominator kit. There are plenty of options out there, but for now, the truck is in its best form.
Last edited:
and custom springs for the rear
that will buff out 
