Airing Down - Load Range C

Hello, frens. I’ve got a DCSB TRD Off Road with 287/70/17 LRC BFG KO2 and I run them at 40psi for city driving.

I would like to air down for some light Northern AZ (Prescott) trails. I’m not going to push my rig through torquey crawls until I have good recovery gear but I want to soften the ride on washboard roads.

TLDR: What is a safe pressure window to run in my tires? I know the LRC sidewalls aren’t great for fighting off jagged rocks and thorns but I’m running those until they’re worn out.

 

For easy trails and washboards 25 is about how low I go since I’m still at speed a lot.

Do some reading and testing out what you like best for your specific trails and uses.

I don’t always carry a compressor so I’m not going down to 15 or less if I have to drive a long way to air back up. If you have one you can go a lot lower.

 

I’ll try 25 psi when I leave the pavement and adjust downward front there.

 

I'm always around 23-25psi off road, I rarely dropped down to 15-20s, just don't forget an air compressor!

 

I mostly use 18 psi when I am off-roading in the desert. I used the same psi when I ran Rim Road (FR 300) for about 40 miles along the Mogollon Rim. I have the the stock Goodyear Wranglers w/kevlar (size 265/70/16) on my 2020 OR DCLB. After an hour or so, I note that they are up to around 20psi due to the heat from both the flexing of the tire and the heat we get in the desert. Most of the time I am below 10mph but have gone as high as 30mph for 10 to 15 mins with no problems. I do have a compressor though to air up before I get back on the pavement.

 

I got my ARB Twin installed.

I tested psi on a few-mile washboard run in the midday New Mexico heat (80-90) at 10 and 20 mph. 20 mph was probably the best speed because the road is two-lane, mostly straight and visibility is great. Not a lot of animal movement at that time of day so there’s a low chance of hitting anything.

40-42 psi rattled all my bolts loose at 10 and 20 mph (not literally but I wanted a baseline for comparison.)
25-27 psi felt better at 20 mph but I could still feel the “skip” when I would get momentum at 20 mph.
19-21 psi seems to be the magic number for washboard. It felt sluggish during acceleration but I glided over the road after that.

For fun, I moved to lesser traveled wood-cutting trail and tried 4L and Crawl Control at 19-21 psi. It’s mostly an incline (15-20 degrees) with lots of wash outs and ruts so I got all the flex my dinky 4WP spacer lift and stock Bilsteins could handle. I hadn’t tried it at higher pressures so I only have one data point but the truck climbed without issue.

I’m now pretty confident in my tires’ ability at 19-20 psi to drive a mix of rough trail and washboard. I’m still going to avoid thorny/jagged trails for a bit until I’ve got more recovery gear though.

 

I run 20-22 psi on those exact same tires.

Most of the time I drive home on the highway at that same PSI and they "heat up" to 24-25. Air them up when I get home. Usually only a 40 min ride to get back.

 

On tougher slow trails I run 14-16. On less technical stuff I will run in the low to mid 20s.

 

If you AZ guys get good beta on some spots, lemme know!


OP fwiw, Matt, from Matt's off-road recovery runs 8psi year round in his Jeep.

 

Does he have bead locks? I have Method 701 with “bead lock technology” but I don’t want to test anything under 15 psi for fear of a sidewall slice or thorns

 

20-25 for sure.

If its just a washboard road, 25 is best simply due to re-inflation times. 5psi x 4 sucks with little compressors lol.

 

My ARB Twin handled all four from 19 to 41 in a handful of minutes. I’m gonna get a few runs with a stopwatch for a more official time and then I’m adding a 2 gal stainless tank along the frame to test the air-up times.

 

You know what, I think he recently got some. But even previously I think he ran around there.