Intro
For 2026, Fox is introducing the new generation of NA3 Glidecore air springs inside all of their 36 forks. The NA3 air spring offers more consistent performance than the previous NA2 air spring through the use of elastomers, allowing the air spring to maintain its alignment as the fork flexes. Featuring backwards compatibility with the previous generation 2021-2025 Fox 36, the NA3 Glidecore Air Spring is a cost effective upgrade for anyone looking to get maximum performance without buying a whole new fork.
The NA3 Glidecore Air Spring uses a brand new architecture that we haven’t seen before from an air spring, using elastomers to separate the air spring from fork flex. All forks flex anytime there is force going through them. Whether that’s from braking, hitting bumps, turning, sprinting, or really anything that happens while riding the bike, the fork will be loaded and conforming to some extent. Typical air springs suffer quite a bit from fork flex, and they bind as the fork chassis twists during normal riding. With the use of elastomers, the Glidecore NA3 air spring is unbothered by this flex, and preserves its supple performance while the fork is flexing. Maintaining alignment is key to buttery smooth suspension performance, and the NA3 air spring keeps the Fox 36 operating smoothly no matter what you’re charging through.
Just like a typical air spring, the NA3 Glidecore Air Spring uses positive and negative air chambers. You can add or remove pressure via a shock pump at the top of the fork, and tune the progressivity of the air spring with volume spacers. Accessing volume spacers is now done with a cassette tool instead of a chamferless socket, much like a RockShox air spring. You no longer need a proprietary tool to change your volume spacers with the new Glidecore NA3 Air Spring, a very welcome change. Volume spacers haven’t changed for this generation, and you’ll use the same volume spacers as the previous NA2 air spring.
Fox NA3 Glidecore Air Spring
- Elastomers allow for compliance
- Reduced breakaway friction compared to NA2 Air Spring
- 140mm, 150mm, or 160mm of travel
- Compatible with 2021-2025 and 2026 Fox 36
- Tunable with volume spacers
- $110 MSRP
Combined with the increased stiffness of the new Fox 36 chassis, this air spring helps close the performance gap between the 36 and 38 forks. While going through rough sections of trail, the 2026 Fox 36 stays supple and tracks a line more consistently, keeping you fresh and in control at all times. The 38 is still a stiffer fork, and while this air spring isn’t compatible with the 38, I bet that there will be an updated Glidecore air spring to increase performance down the line.
While the previous NA2 air shaft ranged from 130-170mm, NA3 is only available in 140-160mm.
Upgrading to NA3 Glidecore Air Spring
Before we get ahead of ourselves, let’s make sure your fork is compatible with the new air spring. A very easy way to tell is by looking at the arch of the fork. If you have a Fox 36 with rounded arch, and you do not have a Fox 36 Rhythm, then your fork is compatible. If your arch is angled like the 2020 Fox 36 or Marzocchi Bomber Z1, your fork is not compatible with the new air spring.
Instead of buying a whole new fork, owners of the 2021-2025 Fox 36 can install the NA3 air spring for the same compliant and supple riding experience. We’re stoked that Fox made this air spring backwards compatible, and we expect lots of riders to perform this upgrade to modernize their fork for a fraction of the price of a whole new fork. This upgrade is very doable for any home mechanic, and adds just a couple steps to your typical lowers service. We have a fork service kit that includes all of the tools you’ll need aside from the air spring itself, as well as a super in depth Fox 36 service guide, taking all the guesswork out of the procedure. While the video is a few years old at this point, all of the steps are the same for the new generation of forks and air springs. Instead of servicing the air spring, you’ll just replace the NA2 with the NA3.
NA3 on the left, NA2 on the right. Same dimensions, different everything else.
Putting the GRIP X2 and NA3 equipped 2026 Fox 36 to work
While you’re upgrading your air spring, consider upgrading your damper to either the GRIP X or GRIP X2 dampers! These dampers were introduced for 2025, which means some of the previous generation 36s used these dampers, but all 2021-2024 Fox 36s used either a GRIP or GRIP2 damper. You’ll get much better performance and adjustability with one of the modern dampers, and you can have all of the same internals as a 2026 Fox 36 by upgrading your air spring and damper at the same time. If you’re looking for all out downhill performance, I strongly recommend the GRIP X2, but if you’re weight conscious and want to watch those grams, the GRIP X offers 90% of the downhill performance at a lower weight.
Conclusion
To sum it up, Fox’s new NA3 air spring uses a novel design with elastomers to increase performance while the fork is under load, and if you’re looking to modernize your previous generation Fox 36, upgrading to this new air spring is a great way to do it. Retaining suppleness while the fork is flexing noticeably increases the tracking ability of the Fox 36, helping you keep traction and control through all kinds of riding scenarios.
SHOP NA3 Glidecore Air Springs
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(360) 306-8827
sales@thelostco.com
ABOUT THE RIDER/WRITER
| NAME | AGE | HEIGHT | LOCATION |
| Tor Weiland | 25 | 5'11" | Bellingham, WA |
Current Bikes: Transition Sentinel, Transition TR11
Bike Size: Large
Favorite Trails: Oriental Express, Upper Bob's
About Me: Hailing from the sunny landscape of California, Tor headed north and landed here in the cloudy town of Bellingham, WA. His riding style is "PINNED" and he loves to scope out those seemingly impossible triples. He loves riding and also loves sharing his experiences with others. You can catch Tor in front of the camera or behind the keyboard, but best of luck catching him on the trail!