lowered tire pressures, full disclosure article

[crikeymike]

This article is something ARB put out in their newsletter a few months back, and it contains some really interesting facts, pictures, and details about how lowering your tire pressure affects the tread on the ground.

If you have a spare 5-10 minutes, take a read through it.

https://docs.google.com/open?id=0B1HkgGJBnd7EY2RmNDViNmMtOTU5OC00ZTA3LTk3OTctMzdhOGVmOGZhNzQ4

Here's a little snapshot of what it contains:

 

[ardentyota]

Cool picture.

 

[tag3]

Link worked for me.

 

[yoopercharged]

Nice find. It's too bad they don't mention ice or snow.

 

[CycloSteve]

I would also think that the tire load rating of C or D or E would also affect the tread pattern.

Theoretically the stiffer sidewalls in the higher load rated tires should also affect the footprint and the higher rated tires can run much higher pressures on the road. That said, I often run 15psi off-road, and into the mid 40s on-road with BFG ATKO Load D 315's. The BFG D's are rated to 50 PSI, and E's to 65 and in some cases 80 PSI!

Odd that they have the graphic and table out-of-whack...the footprint goes up from L-to-R, and the table goes down...just a niggly issue, as the message still is the same, drop the PSI when off road to get more traction.



Steve

 

[clouter]

link doesnt work

but i have bfg ATs in 285/75R16 usually running at 35psi, how much can I put in for highway use to have the best fuel mileage ?

thanks

 

[Douglas S]

link doesnt work

It works for me...interesting read.

 

[tromz]

nice ! As we all know and now proven the best gains are btw 15 and 20 psi

 

[angerhater]

at what pressure does it become easy to unseat the bead?

 

[crikeymike]

link doesnt work

It's in google docs. I'm not sure if one browser would/wouldn't work, but it is a PDF, so you'll need adobe reader for it.


Yeah, the chart thing is a big ridiculous, but it makes us pay more attention, right!

 

[crikeymike]

For those who can't get the link to work, here's another photo clip from the whole PDF.

 

[ardentyota]

Found the non pdf version:
The Lowdown, Off Road Tire Pressures | ARB USA Blog

 

[Ebag333]

nice ! As we all know and now proven the best gains are btw 15 and 20 psi

Well technically at 0 PSI would be the best gain. You can't get any better than that.

at what pressure does it become easy to unseat the bead?

Depends on the tire, rim, surface...etc etc etc.

If you drive uber careful and on a slick surface you can get away with a lower PSI. I ran 7 PSI on my 35" AT's for a short distance. Only reason I didn't blow the bead was I was on an extremely slick surface (wet clay)...that and a lot of luck.

OTOH, run a dual beadlock and you can run 0 PSI without blowing the bead.

 

[80t0ylc]

..................but i have bfg ATs in 285/75R16 usually running at 35psi, how much can I put in for highway use to have the best fuel mileage ?

thanks

Sidewall of your tire should tell you the max pressure for the max load rating for your tires. You should be able to safely run at any weight, up to that max load, at the max pressure. Your fuel mileage will be better at the highest tire pressure but, your tire wear will be uneven across the width of the tread. It will wear more in the middle as the pix in the OP's link showed why: Sides of the tread barely making contact with the road. So, it's a trade off. Less rolling resistance = better fuel mileage.

Do you want to have premature wear on your tires and the best fuel mileage that your tires can give?

or

Do you want the most miles out of your tires with slightly less fuel mileage?

 

[hawaiicruz]

Sidewall of your tire should tell you the max pressure for the max load rating for your tires. You should be able to safely run at any weight, up to that max load, at the max pressure. Your fuel mileage will be better at the highest tire pressure but, your tire wear will be uneven across the width of the tread. It will wear more in the middle as the pix in the OP's link showed why: Sides of the tread barely making contact with the road. So, it's a trade off. Less rolling resistance = better fuel mileage.

Do you want to have premature wear on your tires and the best fuel mileage that your tires can give?

or

Do you want the most miles out of your tires with slightly less fuel mileage?

I'm running 40 psi on my bfg ATs load range D, seems like a good compromise between mileage and wear. 15 psi off road, haven't broken a bead yet ( fingers crossed)

 

[cartercd]

I did similar measurements on my Revos a while back. My truck's weight is close to stock.

 

[ybhc]

link doesnt work

but i have bfg ATs in 285/75R16 usually running at 35psi, how much can I put in for highway use to have the best fuel mileage ?

thanks

Well for the best milage that would be whatever the max PSI is on the tire sidewall (and maybe a couple more on top of that).

This will also result in dangerous handling, reduced stability, reduced traction, reduced comfort, and general... dangerousness.

 

[western flyer]

I learned something today. Thanks crikeymike.