When and Why to Use Compression Adjusters on Off-Road Shocks
In this article we will demonstrate when to use compression adjusters on your shocks. This will be helpful to those who already have adjusters on their shocks or are interested in buying shocks that have adjusters. We will reference compression adjusters from Fox, King and Ride Shocks.
What are Compression Adjusters on Off-Road Shocks?
Some high end shocks offer compression adjusters for additional performance. These adjuster knobs are typically found on the end of the remote reservoir which allow you to manually adjust the compression damping on the shock. Adjustable offroad shocks usually come with one or two knobs depending on which types of adjustments they offer.Â
Compression adjusters work by controlling oil flow into the reservoir when the shock is cycling. When a shock compresses, some of the oil flows from the shock body, through the adjuster, and into the reservoir. By restricting that oil flow, the adjuster increases resistance, effectively making the shock feel firmer. Most adjusters offer around 10 to 20 clicks of adjustment. Note that each click is not made equal and is not representative of the total amount of adjustment. Too many clicks can also be tiring to make while too few doesn’t provide a fine enough range of adjustment. Each shock manufacturer has their own design which we will discuss below.
Fox Shocks DSC Adjusters
Fox Shocks offers a DSC (Dual Speed Compression) adjuster on select OEM and universal fit shocks. This adjuster features two knobs that allow for both High and Low Speed Compression tuning. The DSC has proven to be a reliable and effective upgrade for those looking to improve shock performance. However, it’s important to note that the high-speed digressive adjuster can influence low-speed performance—depending on how the LSC is set—and may introduce added harshness in certain conditions. Learn more about Fox DSC Adjuster here: Article 1, Article 2, Article 3, Article 4
Fox Shocks DSC Evo Adjusters
Fox’s new DSC EVO Adjuster, released in early 2025, represents a significant evolution in compression adjustment. Currently available only on select OEM fit applications, this redesigned adjuster refines performance by separating tuning characteristics more effectively. The low-speed knob controls bleed adjustment, allowing for smoother tuning of chassis movement and small bump sensitivity. The high-speed knob now adjusts digressive damping by increasing the spring rate of the high-speed valve stack, offering more consistent resistance during big hits and sharp impacts. This new design is a notable improvement over previous versions, delivering better overall control, comfort, and performance. Learn more about Fox DSC Evo adjuster here.
Fox LSC Adjuster
Fox Shocks features a Low Speed Compression (LSC) adjuster exclusively on their 2.0 Performance Series Shocks. This single-knob adjuster provides 8 clicks of precise low speed compression tuning. It works by adjusting small amounts of bleed around a digressive compression stack, offering subtle but effective changes in ride quality. The LSC adjuster is an affordable upgrade for customers who want the performance benefits of 2.0 shocks with added control over low speed compression. Note that the FOX LSC adjuster is a one size fits all and is digressive, which can result in added harshness, especially on lightweight vehicles.
King Shocks Mid Speed Adjuster
King Shocks feature a mid-speed adjuster with linear valving on nearly all of their OEM and universal fit shocks. This adjuster uses a single knob to provide a balanced range of both high and low speed compression tuning, with 24 clicks of precise adjustment. It operates by adjusting large amounts of bleed around a linear disk stack—delivering mostly high-speed compression changes when fully open, and transitioning to low-speed adjustment as it’s closed down. The result is a versatile and linear tuning range that suits a wide variety of terrain and driving styles. Learn more about the King Mid Speed Adjuster here.
Ride Shocks DPA Adjuster
All Ride Shocks come equipped with the DPA (Dual Piston Adjuster), which is standard across the entire lineup. This adjuster features two knobs—gold for lowspeed and blue for highspeed—allowing independent control over each compression range. The DPA delivers a smooth, linear adjustment curve by controlling bleed around two separate compression stacks: the first for low speed, and the second for high speed. This setup provides precise tuning across a wide range of conditions, giving drivers the control they need for both comfort and performance. Learn more about the DPA adjuster here.
When to use Compression Adjusters on your Shocks
Now that you have a basic understanding of compression adjusters, let’s explore when you might want to tweak them to enhance ride quality and performance. Keep in mind that ride quality and ideal settings are subjective and vary based on each person’s preferences and driving needs.
Low Speed Compression Adjustments
Low-Speed Compression (LSC) refers to the shock’s resistance to slower, more controlled shaft movements—such as those experienced during cornering, braking, accelerating, or driving over rolling terrain. Adjusting low-speed compression affects how the suspension responds in these situations, helping improve ride comfort, body control, and overall stability.
Tech Tip: If you have high and low speed compression adjusters, we recommend making changes to the low speed adjuster first if your suspension feels too soft.
Low Speed Compression Examples: Cornering, braking, accelerating, rolling bumps
When should you add LOW speed compression, increase compression damping:
If you are loading up your truck or SUV for a weekend camping trip, this is a good time to add low speed compression. It’s easy to get carried away with packing all your favorite camping gear which can add a tremendous amount of weight to the vehicle. Since it’s not easy to change spring rates, making changes to the compression adjusters is the next best option. With all this added weight, you will likely experience the vehicle bottoming out and it may feel too soft or bouncy. By adding low speed compression, the shocks can help alleviate some of those issues.
Tech Tip: It is recommended to leave the adjuster at least one click open or it may get harsh.
When should you remove LOW speed compression, reduce compression damping:
If your suspension feels harsh over small bumps or washboard roads, you may have too much low-speed compression. Excessive low-speed damping can make the suspension less responsive to minor, rapid inputs, resulting in a stiff, uncomfortable ride.
Reducing low-speed compression can help the shocks react more freely to these small, sharp impacts—smoothing out the ride and improving comfort without compromising control. Make adjustments in small increments to dial in the ideal balance for your setup.
High Speed Compression Adjustments
High-Speed Compression (HSC) refers to the shock’s ability to manage rapid, forceful compression events. This type of compression is triggered by sudden impacts, such as hitting curbs, speed bumps, potholes, larger rocks, or washboard terrain—regardless of how fast you’re driving.
While vehicle speed can contribute, what truly defines high-speed compression is the rate at which the suspension compresses. For example, cruising over a gradual rise at 75 mph engages low-speed compression due to the slow, smooth suspension movement. In contrast, hitting a sharp speed bump at just 15 mph causes a fast, abrupt compression—activating the high-speed circuit.
Properly tuning high-speed compression helps control these quick impacts, reducing harshness and preventing bottom-outs without compromising overall ride quality.
High Speed Compression examples: Curbs, speed bumps, relentless washboard roads
When should you add HIGH speed compression, increase compression damping:
If you find yourself bottoming out on whoops while driving fast off-road, and your low speed adjuster is more than half way closed, you should consider adding more high speed compression. This will help firm up the suspension and help avoid bottoming out as easy. It is recommended to make small changes to the adjuster settings rather than closing the adjuster completely.
When should you remove HIGH speed compression, reduce compression damping:
If your suspension feels too stiff, it’s a good idea to check your adjuster settings. It’s easy to lose track of where they were last set, which can lead to a harsh ride—especially when transitioning between different types of terrain.
When making adjustments, be sure to tune both the high-speed and low-speed compression knobs. Increasing high-speed compression without adjusting low-speed can create an imbalance, making the suspension overly firm on small, choppy terrain like washboard dirt roads. Properly balancing both settings ensures a smoother, more controlled ride across varying conditions.
Adjustment Range
This article covered just a few of the compression adjusters available on the market. It’s important to note that not all adjusters are created equal—each offers different levels of control and adjustment range.
If you find yourself maxing out the adjusters and still not getting the ride you want, that’s a strong sign the internal valving may not be right for your driving style. For instance, if you prefer your shocks set to full stiffness, the current valving is likely too soft for your needs.
In cases like this, a custom revalve from a shop like AccuTune Offroad can make a big difference—tuning your Fox, King, or Ride Shocks specifically for your vehicle’s build and your preferred ride characteristics.
Top 5 Applications that Need Compression Adjusters
#1 | Overland Adventure Vehicle
Compression adjusters are a great upgrade for overland builds that carry heavy camping gear for extended trips. They help maintain ride quality and control by compensating for the added weight and shifting loads.
#2 | Towing a TrailerÂ
Compression adjusters are an excellent upgrade for vehicles that tow trailers, as they allow you to compensate for changes in tongue weight and maintain better control and ride quality.
#3 | Performance Focused Vehicle BuildÂ
For the enthusiast looking to fine-tune ride quality, compression adjusters offer the flexibility to dial in performance. Whether you’re commuting during the week or hitting the trails on the weekend, adjusters let you tailor the suspension to match both driving styles.
#4 | Off-Road Racing ApplicationÂ
Compression adjusters provide the ability to make fine-tuned changes on the fly, making them ideal for racing conditions. Stiffening the adjusters mid-race can help combat shock fade and maintain consistent performance as the course and pace change.
#5 | Off-Road Only / Trail Rig ApplicationÂ
For an all-purpose trail rig that tackles everything from high-speed desert runs to slow-speed rock crawling, compression adjusters are a great addition. They allow you to adapt your suspension to a wide range of terrain and driving conditions for optimal performance and comfort.
Summary
Adjusters can be a great feature to have on your vehicle if you want the best ride quality possible. Compression adjusters can really come in handy for those who occasionally add weight to their vehicle for a camping trip or increased tongue weight from towing a trailer or want to increase off-road performance without sacrificing on-road comfort. Keep in mind these adjusters allow for mostly fine tune manual adjustments. If you are maxed out on your adjusters, it may be time to have your shocks revalved by the experts at AccuTune Offroad.
Pro tip: If you choose to not invest in Fox or King adjusters, they can be added at a later time but are extremely expensive. If it is something you are considering, we highly recommend going with them from the beginning. If you still choose not to get compression adjusters, definitely purchase Fox or King shocks through AccuTune Offroad so at least the compression & rebound valving inside the shocks are tuned for your vehicle.Â
