A couple of observations about this video:
As TMW noted, the truck had locking diffs front and rear. That provides roughly 4x the traction available to a 2WD truck, and 2x more than a typical
4x4 with standard open diffs. That truck engine likely had way more than the average amount of torque.
I've found that at times, turning the steering wheel back and forth can assist; also at times while hunting for traction on loose hill climbs and on
mud. But it is no magic solution as presented. It had more to do with locking diffs, torque at low rpm, and airing down.
Regarding airing down, he recommended 15-20 psi in the video. That is too much air for optimal flotation with those tires and on that truck. The truck
made it out, but it is important to know that it could have done even better. Nearing the end of the video, the truck pulls onto flat sand. The slight
bulge in the BFG AT's is noticeable, but not close to the threshold where there is risk of popping off the wheel bead. He could run dunes at 11-12
psi. To get unstuck, 10 psi. And if that doesn't do it, 8 psi, but only long enough to get out of the hole and unstuck.
That appeared to be a regular cab 1/2 ton truck. Unloaded, approx. 4,500 lbs. A heavier truck (1-ton, quad cab, diesel engine, and/or with a camper)
would need a little more air. Add 2 or 3 psi to the above numbers.
When deflating, keep an eye on the sidewall. Ideally, the tire will make a smooth, uniform rounded bulge. Tires with stiff sidewalls may not bulge
much as you air down until they buckle and form a crease. Crease = bad, so add a little more air to avoid damaging the tire and rim cuts.
I ran dunes (Glamis/Gordon's/Buttercup) with a 3,600 lb. Wrangler for a couple decades, both with rear paddles or on four 33 x 12.50 BFGs, locking
diffs front and rear, bored & stroked I-6 making 260 hp. Keeping up with the buggies, I popped the beads a very few times running hard and
jumping. Overall 10 psi was a good number. If the sand is wet and hard, air up to 14+ psi when deliberately pulling hard sliding turns (don't ask how
I know
I just noticed that what I had assumed were fake/cosmetic beadlock wheels on that truck may actually be true beadlocks. Beadlock wheels will
accommodate even lower psi.
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