275/60R20 Air Pressure

[ptwobjohnson]

Anyone know what the proper air pressure would be for 275/60R20 tires on my R1T? I'm going with a slightly smaller tire than stock and wanted to know the correct tire pressure.

Sponsored

 

[Eric9610]

Pressure rating is listed on the tire.

 

[ptwobjohnson]

No, that's the pressure for the max load carrying capacity of a tire. Proper tire pressure is typically on a sticker mounted to the b-pillar just inside the driver side door. However, those values no longer apply to me as I'm switching to a slightly smaller tire.

 

[NY_Rob]

As long as the new tire's max pressure is above the door sticker value, you can safely use that door sticker air pressure.

What's the max PSI for the new tires?

 

[ptwobjohnson]

80psi is max psi for new tires. I'm looking for the correct air pressure to ensure proper tire wear.

 

[NY_Rob]

80psi is max psi for new tires. I'm looking for the correct air pressure to ensure proper tire wear.

There is no "correct pressure" listed anywhere for non-oem tires on a Rivian vehicle.
You'll have to try pressures below your new tires max rating and see how it rides and how the tires wear. I'd start with the factory pressure listed on the door sill sticker and go from there.

FWIW- when you replace OEM tires at a tire shop with other brand tires, they fill them to the pressures listed on the door sill sticker as long as those values are below the tire's max PSI rating.

 

[cohall]

Smaller tire = smaller contact patch. For equivalent contact patch to OEM 20’s, you would slightly lower tire pressure vs OEM recommendation. However, the size difference is pretty minimal in this case, so personally I’d be inclined to just keep running at 48 for the potential efficiency bump. I would then adjust if I noticed any negative impact on driving dynamics Or ride comfort.

 

[Ow My Balls]

You will need to look up the load rating chart for the tire you want to use. I’m currently on Toyo open country III EV LT in 275/60r20 and the load rating puts me at 62 psi to match the 48 psi of the 21” oem tires. What tires are you looking at?

 

[ptwobjohnson]

You will need to look up the load rating chart for the tire you want to use. I’m currently on Toyo open country III EV LT in 275/60r20 and the load rating puts me at 62 psi to match the 48 psi of the 21” oem tires. What tires are you looking at?

I'm looking at the Michelin LTX M/S in 275/60 20.

 

[Mark_AZR1T]

You will need to look up the load rating chart for the tire you want to use. I’m currently on Toyo open country III EV LT in 275/60r20 and the load rating puts me at 62 psi to match the 48 psi of the 21” oem tires. What tires are you looking at?

This. Load rating is the KEY for setting tire pressure. I run 65psi on my Cooper XLT tires (rated 80psi), so I have similar range to the 50psi OEM Scorpions AT tires. My Coopers have perfect wear at 39,500 miles and still have 7/32nd tread on all four.

 

[Dark-Fx]

Start at 48 psi, do the chalk test.

 

[Ow My Balls]

I'm looking at the Michelin LTX M/S in 275/60 20.

Assuming you are using the load index of 116, 48 psi is the pressure you should use when cold.

 

[LL75]

I'm looking at the Michelin LTX M/S in 275/60 20.

Max psi is this is 80?​

 

[CrazyOne]

Smaller tire = smaller contact patch. For equivalent contact patch to OEM 20’s, you would slightly lower tire pressure vs OEM recommendation. However, the size difference is pretty minimal in this case, so personally I’d be inclined to just keep running at 48 for the potential efficiency bump. I would then adjust if I noticed any negative impact on driving dynamics Or ride comfort.

I believe the contact patch size remains the same. The shape will vary.

Reason is, for a given PSI and weight, the patch size has to remain same to support the weight.

 

[R1Thor]

Start at 48 psi, do the chalk test.

This is the right answer.

There's a lot of other misinformation on this thread that I'd...caution you to heed.

Some individuals have also had success reaching out to the tire manufacturer and explaining "I'm putting your tire on this vehicle" and they've provided guidance.

But ultimately, chalk test is the best option. There are some online calculators to compare load ratings of your tires to your vehicle GVWR and that gives you a general pressure, but they only work within a small window of accuracy (example: mine math'd to 36psi. WAY to low). That said, it WILL vary based on the tire you chose, its load ratings and ply.

Here's a quick guide:

Chalk Test for Determining Optimal Tire Pressure

1. Gather Materials
   • White chalk (preferably sidewalk chalk)
   • Tire pressure gauge
   • Air compressor or access to a pump
2. Prepare the Vehicle
   • Park the vehicle on a flat, level surface
   • Ensure tires are cold before starting the test
3. Mark the Tires
   • Use chalk to draw a thick, straight line across the tire tread (from one side to the other)
4. Drive the Vehicle
   • Slowly drive the vehicle forward for about 50–100 feet on a dry, even road
   • Try to maintain a straight path
5. Inspect the Chalk Wear
   • Even wear across the tread → Tire pressure is correct
   • Worn off in the center only → Overinflated; reduce pressure slightly
   • Worn off on the edges but not the center → Underinflated; increase pressure slightly
6. Adjust and Repeat if Necessary
   • Adjust tire pressure in small increments (2–3 PSI at a time)
   • Reapply chalk and retest until even wear is achieved
7. Final Check
   • Once optimal pressure is found, check and adjust all tires to match
   • Record the pressure for future reference

This method ensures even tire contact with the road, improving traction, handling, and tire longevity.

Sponsored