TIRE PRESSURES?

We have been talking about tire pressures and "airing down". I have been doing that as a matter of course, for years..BUT then the question came up: "Air down to what?". I cant honestly remember ever checking the lowered air pressure. I do it till they "look right'...Anyone have any suggestions on the correct pressure? Thanks

every tire is different. last october at la bocana we headed north to the beach with the same 18ish pounds in each tire. the tide was just going out so i hugged the wet line trying to find the firm spot. i sank almost to the frame.

the chinese fire drill ensued with me letting more air out of all 4 tires while Bia grabbed the shovel from the back to dig out the sand in front of each tire. this while each wave came to within 10 feet of us (i read the tide book right, RIGHT???)

we survived that potential fiasco with the knowledge that Your Pressure May Vary daily due to the conditions, not to mention your tire....

You may have to experiment and naturally have a air pump to re-inflate. The type that connects to the battery with clips is three times faster than the type that plug into a cigarette lighter.

As stated above, vehicle type, load, and tire type has a lot to do with how much air to remove.

For deep sand, beach sand on the Cortez side (more difficult than the Pacific side sand)... more air needs to be removed.

Street or bald tires do better. All Terrain tires do well. Mud terrain tires and 3 ply sidewall tires do poorly... if all these types are at the same air pressure.

To equalize them for sand floatation (that's the key, to float on top and not dig in), more air needs to come out of a mud terrain tire than an all terrain or street tire.

The goal is to be able to drive across the soft, dry sand without struggling for power... a sign you are digging in more than you are moving forward.

Typical for all terrain tires is to drop the pressure 50%, and for a mud terrain or 3 ply sidewall/ heavy tire to drop 75%...

This depends on the vehicle weight, load in vehicle, climate (dry air vs. humid air) and of course the type of sand.

Experiment! If you start to get stuck in sand... stop, clear away built up sand from the tires, and let more air out until you find the sweet spot for pressure that day.

When deflated, avoid sudden turns or hard braking... roll to a stop and make wide turns... don't risk the trie popping off the rim if your pressure is less than 10 psi.

The tires I now run on my Tacoma are Hankook Dynapro ATM 265/76-16 and 18 psi is their sweet spot (35 psi on the street). The BFG Rugged Trail TAs that it came with worked fine at 15 psi (32 psi on the street)... I have gone as low as 8 psi once, when I was getting stuck between the incoming tide and a sand dune, after stopping to check out a dead whale on Shell Island about 9 years ago.

BEFORE and AFTER DEFLATING (7-18-10):

At 32 psi and with traction control in 4WD-HI, I was able to drive across the soft sand and onto the wet sand, but as I was fully loaded, the excess weight caused the tires to dig into the loose, wet gravely sand (crushed sea shells).

I dropped to 15 psi, and drove ahead with ease... I circled back to take photos of the difference...








When correctly deflated, the tires will not go as deep into the sand as a human foot print!





I repeated the test with the new Dynapro tires...







So, if you are struggling in sand, let out more air!

I think I'd rather practice at a llantera.

Sometimes, when I lower the tire pressure I wake up the following morning with a flat tire.

I have 285/75-16 E tires. That was with the camper on. Fully loaded with the camper, boat, motor, honda 90, and all the extra crap, I would guess 2000 lb. max on top of the truck. The tires look pretty flat at 15 to 20 psi.



[Edited on 4-22-2012 by msteve1014]

If you air down and rub your street tire sidewalls against sharp rocks, this is what you get.

sidewall protection is muy importante!




[Edited on 4-22-2012 by Curt63]

Anyone have any experience with dualies on soft sand? Have always wanted to take the moho to Pismo and Baja but would hate to get it stuck.

Quote:

Originally posted by El Camote Anyone have any experience with dualies on soft sand? Have always wanted to take the moho to Pismo and Baja but would hate to get it stuck.

Don't cry for me.

Quote:

Originally posted by El Camote Anyone have any experience with dualies on soft sand? Have always wanted to take the moho to Pismo and Baja but would hate to get it stuck.

I went through some very deep sand in my old Jamboree 24 with duallys. I did air way down to between 15-20 psi. This was in Vallecito Creek where Bow Willow Wash converges with it.

I did NOT stop, however. Too afraid!!!

Quote:

Originally posted by El Camote Anyone have any experience with dualies on soft sand? Have always wanted to take the moho to Pismo and Baja but would hate to get it stuck.

YES... Art does (edm-1)!

Here was still too much air, even with 4WD and lockers front and rear:





Here is once enough air was removed... like night and day!:

Quote:

Originally posted by Curt63 If you air down and rub your street tire sidewalls against sharp rocks, this is what you get. sidewall protection is muy importante! [Edited on 4-22-2012 by Curt63]