How to Tune Your Jeep Gladiator’s Suspension with FOX Shock Upgrade
Why Compression Adjustability Matters
Despite advances in factory suspension, most modern off-road vehicles still lack easily adjustable compression settings. Compression tuning, or controlling how quickly a shock absorber compresses, can make or break your Jeep’s ride quality and off-road control.
Too little compression and your Gladiator will feel loose and blow through its suspension travel. Too much, and the ride becomes stiff and harsh. With unique setups from one Jeep to another—larger tires, steel bumpers, roof tents, gear loads—having the ability to adjust compression on-the-fly is essential for optimal performance.
The FOX Factory Race 3.0 Upgrade
For our 2020 Jeep Gladiator Rubicon, we chose the FOX Factory Race Series 3.0 Internal Bypass Shocks with DSC (Dual-Speed Compression) adjusters. These premium shocks allow quick tuning of both high-speed and low-speed compression via external knobs—no tools or teardown required.
What Is DSC (Dual-Speed Compression)?
DSC adjusters are external dials on the shock reservoir that allow for independent tuning of low- and high-speed compression settings.
- Low-Speed Compression: Controls slow suspension movements like body roll, cornering, and weight transfer. Increasing this setting tightens on-road handling—ideal when carrying extra gear or towing.
- High-Speed Compression: Regulates fast suspension inputs like potholes, washboard roads, or unexpected bumps. Adjusting this keeps the suspension from bottoming out during aggressive impacts.
Why Choose FOX 3.0 Internal Bypass Shocks?
The FOX 3.0s offer several key advantages:
- Internal Bypass Design: Allows fluid to bypass the main piston inside the shock body. This improves ride quality by smoothing out small impacts while maintaining control during larger ones.
- Massive Diameter: The 3.0-inch shock body offers greater fluid volume, reducing heat buildup and increasing consistency.
- Race-Derived Cooling: Finned reservoirs and FOX’s Recirculating Reservoir Bridge keep shock temperatures low—even under heavy abuse.
10,000 Miles of Testing: On-Road & Off-Road
After 10,000 miles of trails, highways, and hauling, these shocks proved to be a game-changing upgrade. Here’s a breakdown of our setup and experience:
Rear Suspension Setup
- Shock Part Number: 883-26-081 (2–3” lift version)
- Travel: 9.7 inches total, 5.5 inches up travel
- Result: Excellent rear control even with our heavy MITs Alloy bed, full-size spare, and gear-loaded trips.
Front Suspension Setup
- Shock Part Number: 883-26-082 (3–4.5” lift version)
- Travel: 10.7 inches total, just over 3 inches of current up travel
- Reservoir Mounting: Behind factory steel skidplate with minor trimming
- Upcoming Plan: Upgrade to 4.5” JKS springs to increase up travel and use more of the bypass zone.
Bumpstop and Travel Validation
To protect the new shocks from bottoming out, we cycled the suspension with the springs removed until full bump. This ensured our bumpstops were set properly and the shocks would remain safe through full articulation.
Compression Tuning in the Real World
From cross-country drives to the Rubicon Trail, tuning the DSC adjusters has made all the difference. While FOX recommends starting 3 clicks in from soft, we typically run:
- 5–7 clicks on both low- and high-speed compression, depending on load and terrain
- 12 clicks available for high-speed
- 10 clicks for low-speed
This flexibility lets us dial in the ride for different trail conditions and added weight.
Suspension Upgrades to Support the Load
Our alloy tray bed adds over 700 lbs to the rear of the Jeep, and the rear suspension needed to match. We upgraded to Dobinsons heavy-duty rear springs to better handle the leverage from the overhang and spare tire.
The result? No excessive bounce, no body sway, and excellent control even with the increased rear weight.
Maximizing Comfort with Tires
Our 40x13.50R17 Nitto Trail Grapplers, mounted on 17x8.5 Trail Ready beadlocks, let us run low air pressure on the trail. Combined with our shocks, this gives us a plush, stable ride—especially on rocky or uneven terrain.
Want to See It in Action?
For a full install guide and demonstration of our Gladiator’s suspension in real conditions, check out the Inside Line video on YouTube.
Frequently Asked Questions: Jeep Gladiator Suspension & Tire Setup
Q: What’s the main benefit of upgrading to FOX 3.0 Internal Bypass shocks on a Jeep Gladiator?
A: The FOX 3.0s provide true race-level damping control with dual-speed compression (DSC) adjusters. That means you can fine-tune both low- and high-speed compression for the perfect balance of comfort and control—whether you’re daily driving, towing, or hitting high-speed desert whoops.
Q: What’s the difference between low-speed and high-speed compression?
A: Low-speed compression affects body roll, cornering, and weight transfer—think everyday driving and smooth handling. High-speed compression, on the other hand, manages sharp impacts like rocks, potholes, and washboard terrain. With FOX’s DSC adjusters, you can fine-tune both settings independently.
Q: Do I need tools to adjust compression on FOX DSC shocks?
A: No tools needed. Both the high- and low-speed compression knobs are external and can be adjusted by hand—making trail-side or driveway tuning simple.
Q: How many clicks of compression adjustment do FOX 3.0 DSC shocks have?
A: The DSC knobs offer 12 clicks of high-speed compression and 10 clicks of low-speed compression. FOX recommends starting 3 clicks in from soft, then adjusting from there depending on load and terrain. We found that often 5-7 clicks in from soft suited us best.
Q: How do I set bumpstops correctly when upgrading to longer-travel shocks?
A: Remove the springs and cycle your suspension through full compression. This allows you to confirm your bumpstop engages before the shock bottoms out, protecting the shock and ensuring full use of available travel.
Q: What spring setup works best when adding extra weight like a steel tray, bed rack, or rooftop tent?
A: A heavy-duty rear spring, such as the Dobinsons HD coils, pairs perfectly with FOX 3.0s when carrying additional static weight (700+ lbs). This combination keeps the Jeep level, eliminates bounce, and maintains proper ride height.
Q: How does tire pressure impact ride comfort with this setup?
A: Running lower air pressure—especially with beadlock wheels—allows the tires to flex and absorb smaller bumps. Combined with properly tuned shocks, it dramatically smooths out washboard roads and rocky terrain.
Q: What replacement tires are good for a Jeep Gladiator?
A: The Grappler lineup from Nitto Tire is highly popular among jeep and off-road enthusiasts. For off-road performance and versatility, the Nitto Trail Grappler M/T is a proven match for Gladiators that see serious trail use. It provides excellent traction, strong sidewalls, and a surprisingly smooth on-road ride. Many positive reviews from Jeep owners also mention the Nitto Ridge Grappler hybrid terrain tire.
If you want a quieter, longer-lasting option with balanced on/off-road performance, the Nitto Recon Grappler A/T is ideal. For overlanding or mixed terrain where comfort matters most, the Nitto Terra Grappler G3 delivers great stability and wet-weather grip while still looking aggressive.
Quick breakdown:
- Trail Grappler M/T – Maximum traction for rock, mud, and trail abuse
- Recon Grappler A/T – Best all-around balance for daily + weekend adventure
- Terra Grappler G3 – Quiet, capable, and confidence-inspiring for overland and daily setups
Q: What size shocks were used in this Gladiator build?
A: Front: FOX 3.0, PN 883-26-082, 3–4.5” lift version (10.7” total travel), Rear: FOX 3.0, PN 883-26-081, 2–3” lift version (9.7” total travel)
Q: Does the FOX 3.0 upgrade affect on-road ride comfort?
A: Yes, in a good way. Properly tuned compression improves body control, reduces harsh bottom-outs and gives a more composed feel at highway speeds or while towing. With DSC adjustability, you can make it softer for daily driving or firmer for loaded trail runs.
More From Driving Line
- Learn more about the 2.5 Fox with DSC Adjusters.
