How to Air Down a Rivian R1T / R1S (Stock 20" Wheels): Off-Road Tire Pressure Guide
Rivian R1T/R1S with LT tire upgrade. How switching from stock Euro-metric XL to LT tires changes your off-road airing down range and minimum safe PSI.
EV Note: This vehicle is significantly heavier than ICE counterparts due to the battery pack. Stay on the higher end of PSI ranges and never go below 20 PSI on standard wheels.
Vehicle Specs
| Spec | Details |
|---|---|
| Weight Range | 6,800 - 7,200 lbs |
| Wheelbase | 121.1 / 135.8" R1S 121.1" (fits MFQ); R1T 135.8" (fits MFQ+) -- LT-tire upgrade on 20" wheel pairing. Using the Rivian factory built-in compressor? You'll need the MFRX adapter hose -- it's a fitting adapter, not a length extension. Skip it if you run a portable compressor. |
| Stock Tire Size | 275/65R20 LT (KO2, Falken AT4W, Toyo AT3 EV) |
| Common Upgrades |
|
| Recommended Hose Kit | MORRflate MFQ+ (MFQ also fits R1S) |
Recommended PSI by Terrain
| Tire Setup | Street | Gravel | Rock | Sand | Mud | Snow | Min Safe |
|---|---|---|---|---|---|---|---|
| 20" LT Upgrade (275/65R20 LT) | 50-55 | 30-34 | 28-32 | 22-26 | 22-26 | 30-34 | 20 |
Notes
Common upgrade from stock Euro-metric XL tires. LT construction provides stiffer sidewalls, better puncture resistance, and more confident airing down. Popular choices: BFG KO2, Falken Wildpeak AT4W, Toyo AT3 EV. Min safe 20 PSI (vs 22 on stock). Heavier tires reduce range 12-15%.
20" LT Upgrade (275/65R20 LT): LT sidewall handles lower PSI better. Common upgrade: KO2, Falken AT4W, Toyo AT3 EV.
Hose Recommendation: Quad+ (MFQ+) + Rivian ext. Shop the MORRflate MFQ+ to air down all tires at once. See all configs and kits →
How to Air Down Your Rivian R1T / R1S
- Park on a flat, stable area before the trailhead.
- Set the parking brake and check current tire pressure with a gauge.
- Use your deflator or MORRflate system to release air to your target PSI (see table above).
- Adjust all four tires evenly. Drive a short distance, recheck, and fine-tune.
- Re-inflate before returning to pavement. Low pressures at highway speeds cause heat buildup and blowout risk.
Safety: Always re-inflate before returning to pavement. Running low pressures at highway speeds can cause heat buildup, sidewall damage, and even a blowout.
Frequently Asked Questions
What changes when I put LT tires on my Rivian?
LT tires have stiffer, more reinforced sidewalls than the stock Euro-metric XL tires. This means better puncture resistance, more confident airing down (minimum drops from 22 to about 20 PSI), and better bead retention. The trade-off is heavier tires (12-15% range loss), more road noise, and a slightly stiffer ride.
What are the best LT tires for a Rivian R1T?
Popular choices in 275/65R20 LT: BFG KO2 (strong off-road, heavy, noisy), Falken Wildpeak AT4W (best ride quality, quieter), and Toyo Open Country AT3 EV (purpose-built for EVs, best efficiency). The Toyo AT3 EV is the most popular choice for Rivian owners who want balanced performance.
How much range do I lose with LT tires on a Rivian?
Expect 12-15% range loss compared to stock Euro-metric XL tires. The heavier construction and more aggressive tread increase rolling resistance. Some owners offset this by running slightly higher street pressure (48-55 PSI on LT vs 48 on stock).
Can I air down my Rivian more with LT tires?
Yes, modestly. LT tires maintain their structure better at low pressures. The minimum safe PSI drops from about 22 (stock Euro-metric XL) to about 20 (LT). More importantly, you'll feel more confident at 25-28 PSI on rocky terrain because the stiffer sidewall resists pinch flats better.
Do I need to recalibrate my Rivian TPMS with LT tires?
The TPMS sensors stay in the wheels, not the tires, so they continue working. However, the warning threshold (set for stock tire pressure) may trigger differently. The TPMS will alert when aired down regardless -- this is normal.
Related Resources
Recommended terrains:
Related articles:
- Rivian Tires: Why Your 7,000-Pound EV Ships on the Wrong Rubber (And What to Do About It)
- Toyo Open Country A/T III: Four Tires, Same Name, Only One Is Right for Your Truck
- Airing Down 101: The Easiest Upgrade You'll Ever Make
- The Off-Road Tire Pressure Cheat Sheet You'll Actually Save
- SL vs LT Tires: What You Need to Know Before Airing Down
- TPMS and Off-Roading: Why Your Truck Is Screaming at You
- Sidewall Height: Why Your Wheel Size Decides How Far You Can Air Down
Recommended gear:
Shop MORRflate Gear Read the Full Guide
Building your own R1T or R1S?
Use my Rivian referral link to configure yours. You get Rivian credit toward gear, charging, or service. Costs you nothing. Helps support the work here. See everything I recommend.
Learn on the trail with a pro.
If you want to feel the difference in person, SNVORA runs hands-on off-road training courses. We cover tire pressure, recovery, and the skills that make trail days safer and more fun.
About the author: CJ Arnesen is the founder of Sierra Nevada Off Road Academy (SNVORA) -- a professional off-road training program based in California. CJ has logged thousands of trail miles teaching airing down, vehicle recovery, and trail navigation to drivers of every skill level.
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