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Discussion Starter #1 (Edited)
There's a lot of discussion in various posts regarding driving FJs in sand.
It's something I've done once or twice, so I thought I could share some advice, and consolidate the discussion.

All about sand...
Sand isn't really that difficult once you understand it, but of course there are a lot of different factors:

- Grain Size
- Moisture Content
- Temperature
- Gradient
- Topography
- Pack Density

Let's start with grain size. Sand can range from a talcum powder like dust to gravel, and there is always a mix of grain sizes in any one location, and they can vary wildly within a couple of meters depending on deposition (wind, water, gravity).

Moisture content - from bone dry to waterlogged. Generally, the finer the grain, the more effect the moisture content has on its drivability.

Temperature mostly affects moisture content. Hot desert sand is dry, and has very little adhesion. Even if the sand is packed hard, it will loosen up very easily.

Gradient - the steeper, the harder it is to drive on it, but gravity can also be your friend.

Topography - from flat sabkha to beaches, to gatch tracks, to small technical dunes to monster dunes, bowls, slip faces.. the list is endless, and so are the techniques for driving.

Pack density is like snow and is affected by grain size mix, temperature, moisture content, and deposition method. E.g. hot, fine grain wind blown dust in the bottom of a bowl or on the Lee of a dune will drag you down to your floor pan in a nanosecond if you're not switched on mentally (or inexperienced).

Vehicle setup
On sand, weight may be a major success factor, depending on the conditions, but in general, a light vehicle will perform a lot better than the same vehicle with an extra tonne of crap in / on it.

Weight distribution. This is not unique to driving on sand, but excessive weight up high is not ideal. The lower your centre of gravity the better. If you must carry additional water, etc, put it in the footwells rather than the roof rack. Roof top tents are not ideal for dune bashing.

Suspension. When doing a suspension lift, only lift it as much as you need to stop the tires rubbing the inside of the wheel arches on compression. The height you need to lift will vary depending on spring rates, weight, etc. On sand, it is my experience that softer springs & shocks are better than super stiff, but the damping still needs to be effective - the vehicle shouldn't bounce after compression - you'll get seasick and your axles will bounce under power, which is no good.

Tires. These are an integral part of your suspension. The most important parts to consider are sidewall height & sidewall stiffness. Some brands are better than others on sand. The generally accepted kings of sand are Yokohama Geolandar AT, and Cooper Discoverer AT3. LT grade tires have stiffer sidewalls for greater weight, and generally aren't needed for our types of vehicles. P rating is better in sand. MT tires are usually super stiff, and not as good as AT.
Remember the width of the tire is not what helps flotation, it's the length of the contact patch that's more important. Think tank v steam roller. On the FJ, 285/70R17 or 285/75R16 (a shade under 33") is a good size - balancing diameter, and minimal rub, and on road performance. Pressure will vary based on the sand conditions, but 20PSI is a good starting point. You can safely go as low as 12 PSI on the front before risking a pop-off depending on your driving style. The rear tires can go a few pounds lower if necessary.

Armour. Less is more. On the FJ, the main vulnerability is from the radiator to the first crossmember after the engine. There is no need for transmission skids or fuel tank skids or rear diff skids beyond the stock items. The front skid will get fairly battered, so 10mm aluminium or equivalent steel. My last front skid was 8mm aluminium, and it had to be replaced after 3 years of use. Most of the damage was done in the year before I lifted the suspension & fitted larger tires.
Front, rear bull bars, sliders - not needed. My plastic bumpers covers are still fine(ish).
I had factory side steps on the vehicle when I bought it - they just grabbed the sand and made it harder to dig under the vehicle during recovery, so they went the way of my stock rubber & suspension.
You may have a need for a steel ARB bull bar (animal strikes mostly), but sand isn't a reason for it. There's not much risk of animal strikes here (If I hit a camel, then I'll need more than a bull bar. Those things are massive), and I don't have a winch, so stock works fine for me.

Recovery equipment

Long handled shovel
Maxtrax
Snatch strap & selection of steel & soft shackles
Hilift jack with offroad base and lift mate
Compressor

If you're on your own, the above would be the minimum and doesn't include safety equipment. The snatch strap can even be used without another vehicle if you're careful!

Recovery techniques

When stuck in sand, stop before you bog yourself to the frame rails. Get out and have a look around before proceeding.
Are you hung up on something? Are you fighting gravity? How's your tire pressure?

If you still have downward pressure on your tires, dig the sand out from in front and behind ALL tires. Drop your tire pressure to around 15 PSI in front and 10-12 in the rear. Lay the maxtrax out in the direction of travel (Downhill. always downhill. Gravity always wins), and kick them down under the tire.
select low range & lock everything that can be locked (centre diff, rear diff, ATRAC on), then have a go at driving out. If you bog again, repeat unless you're on the frame rails. Then it's time to bring out the big guns...

If the sand is touching the bottom of the vehicle/frame rails, then unleash the Hilift...

To be continued...
 

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for someone with very limited experience driving in sand on the beach for fishing(drive, find a spot, park, drive back home) the only thing i have ever needed to do is air down. this is with a 2002 jeep grand cherokee, and 2012 honda pilot. i would put both into 4x4 part time, which i guess the equivalent for the FJ is 4HI. with the aggressive BFG ko2 tires i was planning on only airing down to about 30psi this summer and going into 4hi. anything else im missing?
 

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Discussion Starter #3
for someone with very limited experience driving in sand on the beach for fishing(drive, find a spot, park, drive back home) the only thing i have ever needed to do is air down. this is with a 2002 jeep grand cherokee, and 2012 honda pilot. i would put both into 4x4 part time, which i guess the equivalent for the FJ is 4HI. with the aggressive BFG ko2 tires i was planning on only airing down to about 30psi this summer and going into 4hi. anything else im missing?
Depends on the sand. This thread is a work in progress, but I'd suggest that 30 on KO2 is pretty high considering how stiff those sidewalls are, and the weight of the FJ. My highway pressure is 32 cold on much softer sidewalls (Cooper AT3). Typically you'd air down to 50% of highway pressure so if you're at 40 on the highway, then 20 would be where you should aim for, but it all depends on the sand conditions. It's a amazing how far you can go before you get stuck on full highway pressure even on hot dry sand.
 

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I have spent a lot of time in the sand in my FJ. I normally air down to 15 psi (KO2's) and run 4 hi. The FJ has zero issues in sand under these conditions.
 

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What a great idea from an expert. I have ran quite a few dunes in California, Nevada and Oregon in the last 35+years of duning on ATVs and now 4x4 vehicles. You are spot on with your posts about grain size and how it can affect climbing or even worse sinking your fj at the bottom of a deep sand bowl. When I run my fj in the dunes I like it at about 10 psi. I do have a question, What have you don to the rear suspension to keep up with the front suspension. It seems that my rear end cannot handle the whoops and rough run ups to steep dunes as well as the front. It is my limiting factor when trying to climb steep tall dunes like Sand Mountain in Nevada.
 

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Discussion Starter #8
What a great idea from an expert. I have ran quite a few dunes in California, Nevada and Oregon in the last 35+years of duning on ATVs and now 4x4 vehicles. You are spot on with your posts about grain size and how it can affect climbing or even worse sinking your fj at the bottom of a deep sand bowl. When I run my fj in the dunes I like it at about 10 psi. I do have a question, What have you don to the rear suspension to keep up with the front suspension. It seems that my rear end cannot handle the whoops and rough run ups to steep dunes as well as the front. It is my limiting factor when trying to climb steep tall dunes like Sand Mountain in Nevada.
My springs are relatively soft, but the rear is definitely the weakness. I get a bit of axle bounce - not notcable, but it's there when you look at the track left in the sand.
Locking the rear diff makes a huge difference - see my signature for the link to lock it in high range.
 

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I would like to add something to this conversation. When I was younger, sometime during the Miocene, I had a 1977 Toyota HiLux pick up. I grew up near the Gulf of Mexico and would go to the beach. This was during a time you could still drive on a beach.

When would get stuck in sand, I would dig out around the buried wheel and start filling it with water. It would cause the sand to pack down so I could drive out.

This truck was 2wd with an open diff. No locker. No maxtrax. No winch. Just me, the ocean, and the poor unfortunate girl I took out there.:jester::jester:
 

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What a great idea from an expert. I have ran quite a few dunes in California, Nevada and Oregon in the last 35+years of duning on ATVs and now 4x4 vehicles. You are spot on with your posts about grain size and how it can affect climbing or even worse sinking your fj at the bottom of a deep sand bowl. When I run my fj in the dunes I like it at about 10 psi. I do have a question, What have you don to the rear suspension to keep up with the front suspension. It seems that my rear end cannot handle the whoops and rough run ups to steep dunes as well as the front. It is my limiting factor when trying to climb steep tall dunes like Sand Mountain in Nevada.
You can apply a small amount of braking with your left foot to take out some of the back-end bounce.
 

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You can apply a small amount of braking with your left foot to take out some of the back-end bounce.
Poor man's ATRAC :rofl::rofl::rofl:
Good idea though - I think a lot of that is traction flip flopping between left & right on the open diff, so the brake will stop the wheels spinning up so much...
That's probably why locking the rear diff helps immensely.

:thinkerg:
 

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Poor man's ATRAC :rofl::rofl::rofl:
Good idea though - I think a lot of that is traction flip flopping between left & right on the open diff, so the brake will stop the wheels spinning up so much...
That's probably why locking the rear diff helps immensely.

:thinkerg:
Not so much for atrac but to reduce the bounce in the backend.

I was out last night and we were on a heavily corrugated road at one point with lots of "woops" (?).... and I tried a bit of left-foot braking to keep the suspension loaded up. Seemed to help a bit.... others in the group tried it as well with similar results.
 

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I've gone as low as 12 psi in the Oregon dunes. You just have to watch out and not cut too sharp going too fast or you can roll a tire off the bead. Normally, I air down to 15-18 psi on the sand. To one of the points that @Iconic made, it's a must to turn off traction control. That'll bog you down before you even get started. Another item that a lot of people forget about is disabling your side curtain airbags. Use the "RCSA OFF" button. That way if you get a bit sideways, your side airbags won't blow on you. I've heard that ATRAC is good for when you do get stuck but I haven't tried it myself. And when you do get stuck, get off the gas immediately. I've helped dig someone out on an uphill dune before that just kept it floored until he was sitting on the frame. That takes forever. :)

When I start, I'm in Park, hold the traction control button a few seconds until it lights solid on the dash. RCSA OFF button, 4-HI on the transfer case and go for it. Sand is a blast.

 
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My wife and I made a run down PINS last month...aired down to 20, kept momentum where it was loose sand and was smooth running in 4HI.

We did see a guy with a Camry down around mile marker 25 or 30, but I assumed he knew the lines and tide times to stay on the more packed sand.
 

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When driving along the beach, I haven't yet had to air down at all, tyre pressure up to 32 psi. For the Namib sand dunes we usually deflate down to 13 psi. That is with Cooper S/T Maxx tyres.
Traction and stability control off and gear selection 4x4 low 3 (auto box) for the dunes, 4x4 HI for the beach.
 

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I get a kick out of reading some of the posters early in this thread saying to the OP from Dubai, basically the universe of sand, that they know all there is to know about driving in sand, though their experience was in one very narrow window of humidity, temperature and type of sand.

I am eager to see what Amaclatch adds to the placeholders in the near future.


Norm "I know nothing about sand" Kerr
 

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Discussion Starter #17
I just added some text in the vehicle setup section
 

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I get a kick out of reading some of the posters early in this thread saying to the OP from Dubai, basically the universe of sand, that they know all there is to know about driving in sand, though their experience was in one very narrow window of humidity, temperature and type of sand.

I am eager to see what Amaclatch adds to the placeholders in the near future.


Norm "I know nothing about sand" Kerr
The most sand my FJ sees is on icy roads in the winter. There's always more to learn.


PS: Found a recent photo of @amaclach going for a drive. Definitely knows his stuff! >:D
 

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Good thread. Good insight.

I just had the opportunity to test out my crawl control at Oceana Dunes and it worked like a champ. I took about 1/4 of my air out and found that 4H was good for relatively flat terrain, but that 4L keeps you from getting bogged down on steeper climbs in the first place.

On one occasion , I was in 4L and purposely stopped short of cresting a steep dune and tried to start again. I began spinning and sinking to the frame. I engaged the crawl and slowly but surely, I crested and was free.

My lesson for the day is that MOMENTUM can be your friend in the deep sand dunes as long as you are aware of the shifting sand drop-offs, rollover dangers, and other drivers that await unseen over the next ridge. My other lesson was that crawl control is noisy, but amazing.
 

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I've added some more content and merged the placeholders into the first post to make easier reading & editing...
 
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