How to get a heavy truck out of the mud?

March 28, 2009 7:27 PM

Let's say your 35,000lb 4x4 is stuck axle-deep in mud....

How do you get it out?

Assumptions: The mud is the consistency of pudding. You have a winch, but the cable is strong enough to tow on level ground and not much more. You are far more concerned with safety and speed of recovery than you are with environmental impact, so whatever you use can be left behind. You've got 800lbft of torque, but it's pushing 17 tons. Your tires are 13in wide. You're most likely going to want to back up onto known terrain.

I plan to test a few possible solutions in a controlled situation, here's what I'm thinking (and, mind you, I don't really expect any of this to work, but I've got to do something): dig out a mud ramp, 15 degrees or so slope, ending as close to the bottom of the rear tires as possible. Place 2'x8' sheets of plywood along the mud ramp. Back out.

Plywood won't work, you say? How about laying down Hesco barriers? Steel diamond-deck?

Could you quickly turn the pudding-mud solid? Some kind of super-quickset concrete? Freeze it?

What am I not thinking of?

posted by csd to travel & transportation (30 comments total)

Dry it?
posted by box at 7:30 PM on March 28

You get a friend with a tractor to pull you out. Or call a tow truck. Anything else is a waste of time.

Unless you have something mighty sturdy within range of your cable you're as likely to pull something down on top of your truck and squish it as you are to winch it out of axle deep mud. More likely actually.
posted by fshgrl at 7:30 PM on March 28

What kind of vehicle do you have that weighs 17 tons? That might help some answerers.

I think you're definitely going to need to do something to give the vehicle more traction (plywood might work if you can get it right up next to the tires). Any chance of getting a stronger cable?
posted by DMan at 7:31 PM on March 28

I'm not a 4x4 driver by trade, but this article is incredibly helpful for all kinds of situations.
posted by phredgreen at 7:33 PM on March 28 [2 favorites has favorites]

Pulleys. Pulleys and more pulleys. There was a Dirty Jobs episode where the host worked with an Army unit to pull huge trucks and humvees out of sand and mud with a brief look at the math behind the systems. Find a person who knows what he's doing and haul that sucker outta there with other power sources, not it's own.
posted by Science! at 7:37 PM on March 28 [2 favorites has favorites]

I was thinking of drying the mud by removing water, but it also might be possible to do it by adding sand or dirt or gravel or something.
posted by box at 7:40 PM on March 28

What kind of vehicle do you have that weighs 17 tons?

A Stryker weighs that much . . .
posted by mrt at 7:41 PM on March 28

Are you really sure you don't want to hire a professional (assuming this is a real, immediate situation)? Your insurance may well not cover damage caused by your efforts, and the only thing worse than a stuck 17 ton 4x4 is a smashed up stuck 17 ton 4x4. Tow trucks deal with broken down busses and trucks all the time, sure they can help you round up more suitable equipment for the job.
posted by zachlipton at 7:45 PM on March 28

A Stryker weighs that much . . .

A Stryker is 8-wheel drive, actually. Sounds like an Army vehicle to me though, or a public utility vehicle or something.

Definitely consider hiring a professional. I didn't think about insurance, and especially if you don't own the vehicle it would be better to get someone to help.
posted by DMan at 7:54 PM on March 28

Also, if you don't own the land the vehicle is on, be particularly careful/hire a professional. You don't want someone suing you for ripping down his tree when the winch+truck assembly drags it down.
posted by zachlipton at 7:58 PM on March 28

Assuming you can't get heavy equipment in¹ then I'd rent some recovery airbags [PDF] (exhaust inflation style) see Video 1, (about 2:30 in this video), 2, 3, and buy either a chainsaw if there are trees around or a good size load of timbers.

Working at one end at a time (so the 4X4 doesn't tip over) dig out enough mud to build a corduroy road style platform under the vehicle's frame plus enough space for your airbag. Use the bag to lift the vehicle and then extend your platform under the wheels. Repeat at the other end. Depending on the load bearing properties of your mud you might need to do this in stages.

Digging a shallow well in the area and pumping out the water may help to increase the bearing capacity of your mud depending on why you have mud.

Unless you can winch mostly up winching will not get you out of thick mud when you are stuck to the axles. The horizontal reactive force is essentially infinite. You've got to get at least partially free via jacking/lifting/digging before attempting to move forward by winching or under your own power.

¹You're trespassing/you're stuck in the middle of your grow op/your 4X4 tractor is stolen/your at a fly in or winter road site etc.
posted by Mitheral at 8:12 PM on March 28

Could you quickly turn the pudding-mud solid? Some kind of super-quickset concrete? Freeze it?

Bags and bags and BAGS of kitty litter.
posted by Cool Papa Bell at 8:25 PM on March 28

There are a lot of guides to doing this -- check out photos of roads in parts of Russia and Africa, among many other places to see why this is an important thing to know how to do safely.

First of all, don't do this. Or this. Be safe -- the forces generated are huge, and it's easy to get killed when a cable snaps.

You can do a lot with careful rigging and pulleys, along with putting things (like sand ladders, logs, etc) under the tires. The better, usually safer (notice the dude in the first video who almost falls into the spinning tire?), and definitely easier solution is to get pulled out by a heavier vehicle on solid ground. Tractors and bulldozers (which can also push you out, if you have a solid enough bumper for them to push on, which is unlikely), along with specialized tow vehicles, are your best bet for extracting such a heavy vehicle.

Military forces use specialized vehicles (example) to extract heavy vehicles stuck in difficult situations. It is unlikely you'd need something that heavy duty to get you out, but in an extreme situation, you'd want the civilian equivalent.

If this is a real question, not a made-up hypothetical, personally I'd start by talking to local farmers and excavation contractors with heavy equipment. A specialized off-road tow, for something that heavy, is going to cost you a fortune -- I'd instead try and find some local guy with a big Cat and lots of heavy chain who'll think it's fun and won't charge you as much.

And next time? Size your winch and winch cable appropriately. Undersized cable is not just useless -- it's dangerous.
posted by Forktine at 9:03 PM on March 28 [1 favorite has favorites]

I've been in a few similar situations, but with much lighter vehicles. A couple of times, digging to get a ramp in place didn't work, so we ended up jacking the vehicle up one corner at a time to get solid material under each tire. Of course, this would require a heavy-duty hydraulic jack and accessible jack points on the vehicle.
posted by gimli at 9:10 PM on March 28

To give you some ideas, check out videos online of stuck trucks. Here's a huge dumptruck getting helped out by some big shovel. Similar. Bulldozer pushing a truck. Two trucks trying (and failing) to return the favor.

And here is a stuck Unimog, which is going to be pretty similar to your situation (though perhaps somewhat lighter). It's not an easy process to get it loose, even with a second Mog.
posted by Forktine at 9:17 PM on March 28

Echoing the other comments - you need to tow it out using something with tracks, like a bulldozer. The tracks spread out the weight. The only alternative is a long enough chain so that the towing tractor is on solid ground. I had an episode of this two weeks ago - got my 4WD truck stuck in the mud, first tractor also stuck attempting to pull it out, but combined enough chains for my second tractor (a WD) to be far enough away to have traction. Chains are safer than cable, too.
posted by rfs at 9:21 PM on March 28

I was deliberately vague (apologies), but here are some responses and additional assumptions:

There are no tractors or other heavy equipment (M88s would be nice) available in the time required. Changing out the winch/cable is not an option, and besides: "Unless you can winch mostly up winching will not get you out of thick mud when you are stuck to the axles. The horizontal reactive force is essentially infinite." The mud is thick (not watery), so airbags, jacks, or water pumps are out (but digging is in). There is no concern for environmental impact or lawsuits from landowners--safety and speed take primacy.

This must be an ASAP recovery conducted by the stuck vehicle and possibly several like vehicles. The corduroy road suggestion is the best direction I've gotten so far, but what do you think about the weight? The materials proposed? The requirement that materials must be brought with the vehicle (can't exactly bring fifty logs)? Are there potential options unexplored in the posted links?

Thanks for suggestions so far. Hopefully, this isn't hopeless. Right now, the best option is "don't go out when it's muddy," which is, um... suboptimal.
posted by csd at 12:22 AM on March 29

I will tell you, from many years of driving farm vehicles, that inexperienced people driving a rig on an unmaintained road or no road at all is asking for trouble. Your best safety is going to be an experienced operator who can read the land and do things like avoid mud holes or lay the log-corduroy road before you get into trouble and several other experienced operators who can team up to get a stuck truck out of the mud. If you're hoping for some kind of magic way for novices to get a dump truck out of axle deep mud: it doesn't exist. Brute dragging force or building a weight bearing road are the best two options. People get hurt doing shit like this, it is not something you can learn on metafilter or the internet in general. Pay the money to get pros in there and learn from them.
posted by fshgrl at 3:05 AM on March 29

I don't know why you are making this more complicated than it is, by unrealistically taking out most of the practical options. This is a well-explored problem -- every farmer deals with this routinely; so do off-road enthusiasts (though with much lighter vehicles), the military, and truck drivers in much of the world. The easy solution is to yank out the stuck vehicle with another (or several) still on solid ground; otherwise you use some combination of sand ladders (or plastic versions, or plywood, or whatever you can find), logs under the tires, winching (including deadman anchors, pulleys, and so on).

Here is a nice overview of techniques for vehicle recovery. There are plenty of specialized books on the subject like this, this, and this. Or hell, just go directly to the US Army's Field Manual for vehicle recovery (pdf link).

Lastly, this:

"Unless you can winch mostly up winching will not get you out of thick mud when you are stuck to the axles. The horizontal reactive force is essentially infinite."

isn't quite so simple. Winching alone might not do it, but the winch combined with digging, putting logs under the tires, and so on, will get you out. Even a decent handwinch (not a flimsy come-along) can be enough to provide the extra pull you need.
posted by Forktine at 6:53 AM on March 29

Dig out the wheels. Insert something like the sand ladder (steel decking maybe?) as far underneath the wheels as possible. Move four feet, move the sand ladder. repeat Ad Naseum

a winch probably won't work
posted by JPD at 7:11 AM on March 29

I think science is on the right track. Block and tackle. If you size it right, your vehicle might only move a few inches at a time, but it would probably be effective.
posted by gjc at 7:40 AM on March 29

Go with the 4x4 advice offered thus far. I've been to a few off-roading events and have seem more than a few vehicles become stuck like yours. The extraction always involves at least on other Jeep, a winch or tow rope, and a lot of carefully timed maneuvering.

And let some air out of your tires. The Jeep fanatics I've been with (who have some pretty crazy vehicles) always "air down" before they roll. Better traction.
posted by jdfan at 8:17 AM on March 29

I don't think what you're proposing is feasible. ASAP and without the proper heavy equipment? 35,000 pounds? Even the oft-derided Hummer H2 only weighs 6500 pounds. If time is really of the essence I think you're better off splitting the load between the remaining like vehicles and abandoning the stuck one. A rush job by people that don't know what they're doing is dangerous and foolhardy. They could spend days trying to get such a vehicle unstuck with no result.

If this is for a real world scenario best not to get into that position in the first place. If this is a fictional scenario give them the equipment and know how to do the job, give them a much lighter stuck vehicle, give them time to do the job, or have them abandon the vehicle (maybe after having spent some significant time and effort attempting to free the stuck vehicle).
posted by 6550 at 9:44 AM on March 29

> Could you quickly turn the pudding-mud solid? Some kind of super-quickset concrete? Freeze it?

That would lock your vehicle in the now-solid earth, since the wheels and rims are narrower in profile than the tires and presumably not sealed.

> 35,000 pounds? Even the oft-derided Hummer H2 only weighs 6500 pounds.

The Unimog U5000 BM437.430 has an empty weight of 9,500 lb and loaded weight of 26,000 lb, which gets you within a half-dozen tons.
posted by ardgedee at 10:04 AM on March 29

Maybe some neighbours will give you a push.
posted by Neiltupper at 11:59 AM on March 29

Start digging.

The only other thing would be to use a doubler and hope the cable holds long enough to move you a few inches. Put a towel or rag, coat, blanket over the cable so if it does snap you are not going to get whipped by the flying cable. You are going to need to get under the vehicle enough to clear a bit of a path for the axels so the tires can raise up. Then, with some space in between the tires and the mud, start filling gaps with tree materials... sticks, logs, rocks, gravel... anything that will raise the axles once you start moving. Build a mound in front of each tire that will raise the vehicle so when it comes down the mound on the other side it will have forward momentum to keep it going. When you get the rig to the top of the mound nail it full throttle so you might keep moving. Have your path dug out as best you can so you don't get too badly bogged down again. Hopefully, you have some traction on your tires so they don't turn into chocolate doughnuts too quickly. Also, remember- once you get to the top of your mound try to clean the mud out of wheel wells and tires themselves... you'll want the traction.

I have an H1 (about 10,000 lbs), I managed to drop the thing in a stream only to get the rear trailer hitch-mounted winch caught between the bank and an unseen tree root. I spun tires till I had it in mud up to the bottom of the door sills. I started digging at 9:30 am. With the winch, a doubler, logs, a setting sun and a crying 6 year old. I managed to free the thing around 6:30 pm. All by myself. It was something I would never want to do again but felt pretty damn proud when I got the thing out. If you got "helpers" you should be able to pull it out much faster, especially if other vehicles are involved. Keep filling the mud till you can raise the vehicle, logs, boulders anything that will get the rig up. Eventually it is going to form a foundation.

If you got any pictures that might help us out in giving you a solution. Good luck if this is real and good luck if you plan on getting that way.
posted by bkeene12 at 8:30 PM on March 29

"If you're hoping for some kind of magic way for novices to get a dump truck out of axle deep mud: it doesn't exist." I suppose that's exactly what I was hoping for.

"If this is for a real world scenario best not to get into that position in the first place." We go where we are needed, and that sometimes means getting stuck.

"That would lock your vehicle in the now-solid earth...." Right, but what if you dug a slope into the mud before sprinkling it with cement? Then hopped into the truck (where it's safer) and waited fifteen minutes? Does this magical cement exist?

I understand its effect of increasing surface area and therefore friction in snow or sand, but will letting air out of the tires help with mud?

@Forktine: Your google skills are unmatched, thank you for the resources. Most of it is conventional wisdom (whereas my situation is a bit unconventional), but you've shown me some things I wasn't aware of. The sand ladder is a good model, and I hadn't seen that Army Field Manual yet.

@bkeene: Thanks for the practical advice and well-wishes. Sorry, can't provide pictures.

Many are saying that this is not a job for amateurs, so we're going to address that. This afternoon, we're going to find some mud in a controlled environment, bury a truck, and become recovery experts. My money's on Hesco Barrier ramps plus winch. I'll report back with our conclusions.
posted by csd at 10:17 PM on March 29

This afternoon, we're going to find some mud in a controlled environment, bury a truck, and become recovery experts.

Here is an example of why you need to take winch safety seriously. And there have been many, many injuries from people getting on the wrong side of a high-lift jack, too.

But that's exactly the right approach -- go get stuck, get out, and do it again. Check out some mud bogging events to see how the professionals go about getting stuck, too. Personally, I'd start with a much smaller vehicle (like a Jeep) and work up from there, but there is a beauty in going whole hog right from the start.

Does this magical cement exist?

No. And it would take a lot more than a thin crust of cement to support your weight, much less your big truck.

(As an aside, mud is a killer on vehicles. If it clogs the radiator, you'll overheat; if it gets into the diffs (say, from the breather hoses going under) bad things happen; and it basically causes wear and tear everywhere it gets. So take cleaning and maintenance seriously, too.)
posted by Forktine at 6:31 AM on March 30

We go where we are needed, and that sometimes means getting stuck.

I can't imagine needing anyone badly enough to help them dig a dumptruck out of the mud. Or having a dumptruck block my road, because it is bogged down. Or have a dumptruck and a bunch of yahoos destroy my road because they never should have been there in the first place. Just saying.

Get someone who knows what they're doing to come teach you how to extract the truck. Much less chance of decapitation or widespread environmental destruction. I know you said you didn't care about environmental destruction but I guarantee you your local authorities will.
posted by fshgrl at 12:40 PM on March 30

Is it just me who's burningly curious about what the "deliberately vague" scenario actually is?
posted by We had a deal, Kyle at 4:57 PM on March 30