Minimum tire pressure for off-roading

Same here when I had my '90 F150 with 6" lift and 36/12.50 R15 Super Swampers. Freaking horrible tires for anything pavement related. Absolutely awesome anything off road related.

 

I wonder if the E load debate is brand specific. I put 60k on a set of e rated ko2s and the ride quality was atrocious. They felt good in corners but they transmitted too much vibration into the cabin both on and off-road. Switched to c load duratracs and it was significantly better. Maybe other brands e load tires don’t ride as rough. Either way I’m sticking to C and D for now on, slightly better mpg, marginally less wear on components due to less rotating mass much more comfortable. For the c rated tires 15-25 psi seem to be the sweet spot. I have gone down to 12psi in sand however. Also throwing $$$ on a lift and nice shocks and then adding tires that will ruin your ride seems counter intuitive to me as well, unless you spend all your time actually rock crawling where bead lock rims and e loads are necessary.

 

really? Which sticker? which line shows the minimum tire pressure to run offroad?
here's my stickers.


@Knute

 

This thread is like the WWE and the special Olympics had a baby lol.

OP, here's the best advice you'll get, find a club or group of wheelers around you and start learning while being out there with others who have been there.

PS, check this out and start from there.
https://www.intercotire.com/using_chalk_method_determining_psi

 

Great suggestion to get involved with a local offroading group. Pick their brains for knowledge.

As for the link to the tire chalk test, that won't help much for driving offroad. The chalk test is used to find the PSI sweet spot for any given tire, on any given truck, for whatever weight that tire is supporting. PSI requirements change as loads are changed.

 

It does help for the exact reasons you stated. If he does it with each load out, then he'll know where the optimal psi is for each load.

 

He was asking about tire pressures for off road driving. Different animal.

For example:
I run between 33 and 37PSI on road depending on load out on 255/85R16 MK3s.

Off road I run 12-18PSI depending on actual terrain, altitude, and load out.

 

Ya, you're right. I've been wheeling for 20+ years and have chalked tires more than a few times and have been doing it wrong all this time.

 

You chalk tires for off road? What does it tell you?


BTW, screw Cali, I live in Oregon now and plan to retire in Montana. See ya when I get there!

 

Here's a video that explains it. It's not just for street use, you also want that optimal tread patch for wheeling some times. Doing it on a road surface just accentuates it more.
https://youtu.be/a2ST54xnhuI

 

OP I have some relevant experience with the stock wranglers.

My first time airing them down I was aiming for 20 psi. Well I overshot that and they all ended up at 14-15psi (according to the TPMS read-out on the dash).
I was somewhat concerned, being my first time airing down and not wanting to lose a bead while traveling solo. But it was getting dark and I didn't want to spend the time to add more air back in.

I drove 11+ miles on a bumpy, washboarded gravel road with plenty of larger rocks strewn about. Then an additional mile on a very rough and rocky unpaved 4x4 trail. It wasn't rock crawling, and surely not as hard-core of a trail as what some others do. But it was intense enough that I was thoroughly impressed by the trucks capability.

I was dark so I probably wasn't choosing the best lines, and I was probably driving faster than recommended because it was late and I just wanted to set up camp and eat something. But I still had zero tire issues. I won't say I wasn't nervous about it, but they held on just fine.

I expected that at 15psi they'd look more flat, but it was hardly even noticeable from the outside.

 

Well, yeah, for those skinny street slicks that come on these "off road" trucks, you can't really go a low as with something like an E rated 33.

That said, your tech is a moron.

For offroad, 15-20 isn't a problem even for street tires.

 

For me, airing down to 12psi is usually more of a comfort thing then a capability thing. I've done plenty of rockcrawling where airing down was critical for traction though...

If you dont air down you are just beating yourself up.


but why argue this when lots of TW members say you will destroy your driveline if you drive in 4wd on pavement.... try airing down to 12psi and rock crawling to create some driveline stress... the truck handles it fine.
sometimes I wonder why I even argue these points... "But chalking your tires is important for offroad traction!..."

 

Technically, yes.

But the increase in traction FAR outweighs the slight loss of clearance.

If you're that worried about that extra inch of clearance, get bigger tires.

 

People don't run E's because they think they can carry heavier loads. If you load up your truck to the capacity of an E tire, you're basically doubling the GVWR of the Tacoma.

1) thicker sidewall doesn't fold over as easy at low pressure
2) are more durable/less prone to flats

If you're running E rated tires for "the ride" you're doing it wrong. E rated tires are better for OFF ROAD. We compromise ride quality and mpgs for off road performance.

 

Im well aware of why people pick load E. I have ran both E and D and wheeled both and have noticed zero difference between the two.

 

You literally said people get "caught up on that load thing".

I was responding to that.

 

Right, people are like

“YOU CANT WHEEL A D, YOUR TIRES WILL EXPLODE.”

Or

“NO WONDER YOUR TRUCK RIDES LIKE A TANK, YOU HAVE E AND YOU NEED D.”


This is what I meant by people getting too caught up in the load rating. I should have added *of LT tires*

 

I gotcha.

You can definitely wheel a D, or even a C, but you are undeniably going to be more prone to punctures with thinner walls, and they don't handle low pressure as well.

I've seen plenty of folks with C's with a punctured sidewall on non technical trails, enough to make me want to avoid them for trails. Last flat I got was back in 2003 on my old 4Runner with BFG m/t's. So I'd just rather err on the side of durability. I don't really care about the "ride" or mpg's, as this isn't my daily driver.

I would say that a good compromise between durability and road handling would definitely be the Ds, but there aren't nearly as many options for those available.

It's all about compromise.

 

I believe the consensus is around 20... although some go as low as 15... Depending on what sort of off road driving you also.