"Safe" tire pressure....

[Qarlos]

I am not knowledgeable at all...but I just weighed my 2 door Bronco badlands sasquatch 2.7 auto with a full tank and it weighs 5020lbs...with that said i was a heavy sweep on the 100 Acre rally in Missouri and on the different stages i was going from 40 to 65 mph on gravel and dirt and sliding like crazy at 39 psi...what would you guys suggest I run in my tires for such a run...I'm not rallying but trying to get to the rally car that ran off the stage...these guys are crazy running at 90 mpg on these dirt and rock roads...any thoughts are welcome!!!

I've been wheeling for 10 years on many types of terrain, except rock crawling. Deflating elongates the tire surface in contact with the ground. The width is unchanged. There are many youtubes proving this point.

The types of tires (road tires versus AT versus MT) will require different deflation levels as will the gross weight of your vehicle.

My personal rules of thumb:
Sand: 15-18 psi (fine tune as needed)
Soft sand: 10-15 psi (fine tune as needed)
Gravel: 18-20psi
Road: 35-39 (whatever the tire recommends)

The main reasons for deflating:
Sand and soft sand: traction (lengthened contact surface)
Gravel: soften the ride without going so low that the sidewalls are exposed to sharp rocks.
Road: fuel economy

I drive fast and have never had a tire failure due to low pressure except one time slashed the sidewall on a rock. However, you do need to mind fast cornering with low pressure to avoid a pop-out of the bead from the rim.

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[Onestepmore]

I've been wheeling for 10 years on many types of terrain, except rock crawling. Deflating elongates the tire surface in contact with the ground. The width is unchanged. There are many youtubes proving this point.

The types of tires (road tires versus AT versus MT) will require different deflation levels as will the gross weight of your vehicle.

My personal rules of thumb:
Sand: 15-18 psi (fine tune as needed)
Soft sand: 10-15 psi (fine tune as needed)
Gravel: 18-20psi
Road: 35-39 (whatever the tire recommends)

The main reasons for deflating:
Sand and soft sand: traction (lengthened contact surface)
Gravel: soften the ride without going so low that the sidewalls are exposed to sharp rocks.
Road: fuel economy

I drive fast and have never had a tire failure due to low pressure except one time slashed the sidewall on a rock. However, you do need to mind fast cornering with low pressure to avoid a pop-out of the bead from the rim.

THIS IS GREAT INFORMATION!!! I've had two jeeps and now the Bronco and never aired down intentionally...but I will from here on out. Do you carry a compressor to re-inflate that doesn't take 20 minutes a tire? Thanks for all the information!!!...Amos

 

[Qarlos]

Do you carry a compressor to re-inflate that doesn't take 20 minutes a tire? Thanks for all the information!!!...Amos

I used to carry an ARB single cylinder compressor. Since I got the Bronco I upgraded to an ABR double cylinder and it halves the time it takes to re-inflate. To inflate from 15 to 39 psi I think it takes about 15 minutes in total.

Nice color Bronco BTW

My onboard compressor. Yes it’s loud in the cabin but no worries about dust if behind the spare tire or in the engine bay:

 

[raqball]

I generally air down somewhere between 18-20 for everything off-road and leave it at that. I don't do hardcore trails or extreme rock crawling though.

I would not recommend that anyone get up to highway speeds, especially if there is cornering, at low pressure as the OP says he does. It's a recipe for disaster..

To air back up, I've always used an ARB onboard compressor in the past but for my Bronco I went with a Power Tank system. Should be here before the weekend. Based on reviews and videos of others using it, It sounds like I'll be able to air all 4 tires back up in under 5 minutes total.

My .02

 

[SROC3]

I used to carry an ARB single cylinder compressor. Since I got the Bronco I upgraded to an ABR double cylinder and it halves the time it takes to re-inflate. To inflate from 15 to 39 psi I think it takes about 15 minutes in total.

Nice color Bronco BTW

My onboard compressor. Yes it’s loud in the cabin but no worries about dust if behind the spare tire or in the engine bay:

What plate did you use to mount that? and the switch section as well. Nice and clean!

 

[Pressurized]

Long time off-road guy that does tires at a medium volume offroad shop... I run 35 on the street on the Bronco and 30 on the Jeep. Off-road, my Staun deflators are set to 11psi for the vast majority of off-roading that I do, mostly rock crawling. If I get in to sand, I'm good with the 11psi unless it's super soft, then I drop to 7psi. It does make a difference.

For fire roads or what I would call "fast off-road", I would probably run 15psi.

For the vast majority of people that I guide, I deflate them to 15psi. If you don't go below 20psi, you don't really get all the benefits of air down. At 20psi and above, the tire doesn't wrap around the terrain as well and you are not getting all of the traction benefits you get at a lower psi. In this case, the lower you go, the better it typically gets.

Obviously, you have to be cautious of going too low without beadlocks... 10-12 is generally ok, but 15 is what I call "safe".

 

[Aonarch]

This video is for the wide vs. narrow debate, but he deflates the tires and takes a tread print, shows them over a pipe and a rock all at various pressures. So it is relevant for the PSI question.

It is a great watch.

I'm team Pizza Cutter.

 

[Qarlos]

What plate did you use to mount that? and the switch section as well. Nice and clean!

American Adventure Labs mount. Custom switch plate by my local buddy’s fab shop.

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