Air down for non technical dirt roads?

[basssears]

Originally Posted by bolty

I used to run 30/40 but lost 3 rear tires so I pay more attention to my rear air pressure, especially in heavy rocks

Bolty, can you clarify what you mean by "lost 3 rear tires"? Too much or too little pressure? Killed them on rocks, overheated on paved roads?

-- Bass

[86Scotty]

Originally Posted by Abitibi

I'm surprised most of you don't air down even more on FSR. I was running 35's on 16" rims with my 10,000lbs ambo and daily ran my tires at 55psi but on FSR I ran them at 22-30psi. Anything above and I would feel a big difference in ride comfort.

New ambo will be running 35's on 18" rims so curious if it will make any difference but I still plan to run them below 30psi on FSR.

Cheers!
David

I should but I'm lazy. There aren't really many off pavement places to go close to me anyway that aren't hardcore rock crawling. To date Moab is one of the few places I've been offroad for long enough to air down. Oh, Alpine Loop Colorado area as well.

[Stenov]

It’s not unheard of to puncture from sharp rocks with too much are. I run at 25-30 on very rough steep climbs but not faster than about 30-35 mph. Smooth ride and less worry about a puncture. Been at 15 psi for severe soft sand work.

[wander]

I had 225/75R16 LT Michelin Defenders and made a chart based on the information from Michelin regarding inflation pressure vs. axle load (below).

I've since switched to Hankook Dynapro Defender AT-M tires for the more aggressive tread (same size). However, I'm still using the same inflation chart.

[geoffff]

Originally Posted by wander

I had 225/75R16 LT Michelin Defenders and made a chart based on the information from Michelin regarding inflation pressure vs. axle load (below).

I've since switched to Hankook Dynapro Defender AT-M tires for the more aggressive tread (same size). However, I'm still using the same inflation chart.

That is the correct approach, as I understand it.
-- Geoff

[geoffff]

I've just added the latest (2020) Toyo table, which has a few new tire sizes:

Tire-Load-Table--Toyo--2020.pdf

And I also updated my Excel spreadsheet with these new values.

-- Geoff

[Twoxentrix]

geoffff, Very good info that is beneficial for many...From a knowledge standpoint as well as Safety.

I'll suggest you begin a new thread with this info (and your spreadsheet since I like it a lot) under a header that would allow our "search function" to locate it easily...I tried several variations just now and this thread didn't pop up at all. I'm sure If I kept going I'd eventually get it to show. Point is, I think it should be much more accessible to others.

This Thread also has many great contributions as well, along with a Formula I copied from an old response JoeH offered years ago...I saved the link back then when I stumbled across it.
https://www.sportsmobileforum.com/fo...sure-9896.html

Combined, the contributions shared by members in these two threads is enlightening and helpful!

[wander]

Thanks, geoffff. I'm definitely saving that chart.

[basssears]

Thanks again to everyone who spoke up... we came out right around 10,000# (about 5600 on the rear) and aired down to 35 front / 40 rear for the worst of the roads and it was a much more comfortable ride. Worst part of our whole drive was the 15 miles of dirt right near home that we were too lazy to air back down for


Good stuff!


-- Bass