No tree, no rock, no fence post: now what? You bury or stake an anchor into the ground itself. Here’s how a deadman anchor works, how to build one from a spare tire or log, and which commercial ground anchors actually publish specs worth trusting.
Pull-Pal, Smittybilt, ARB, Deadman Off-Road, and WARN are trademarks of their respective owners; RiggingOps is not affiliated with or endorsed by any of them.
Before you dig: follow your winch manufacturer’s instructions for spooling, freespool/clutch engagement, and line handling. Where this article differs from your manual, the manual wins. Your winch’s clutch and freespool mechanism differs by brand and model, so check your manual before disengaging it. Keep everyone clear of the load path during a pull, use a winch damper over the line, and never exceed the rated capacity of any component in the system. WARN’s own winching guide recommends laying something over the winch rope midway between the winch and the anchor point to absorb energy if the line lets go.
First, Exhaust the Easy Anchors: Vehicles, Rocks, Existing Structure
A buried anchor is slow to build and hard to rate. Before you pick up a shovel, look for something already rooted to the ground. WARN’s guide lists natural anchors (trees, stumps, rocks) and is blunt about the standard: you have to be certain the anchor will hold the load and that your strap or chain won’t slip.
No tree or rock in reach? A second vehicle can serve as the anchor. WARN’s guidance calls for putting that vehicle in neutral, setting the parking brake, and blocking its wheels before it takes the load. That’s almost always faster and more predictable than digging, and it’s worth ruling out first.
Only when none of that is available (open desert, dunes, a flat gravel wash) does a ground or deadman anchor become the right call.
The Deadman Anchor: How Buried Mass Holds a Pull
A deadman anchor works by burying something with enough surface area (a log, a tire, a steel plate) so the undisturbed soil in front of it has to shear before the anchor moves. The anchor itself isn’t what holds the load. The soil is. That’s why soil type and depth matter more than the size of whatever you bury.
This is also why no single “good for X pounds” number exists for an improvised deadman. Depth, soil density, moisture, and the angle you pull at all change the outcome, sometimes by a factor of three or more in the exact same hole, just dug deeper.
Burying a Spare Tire as a Winch Anchor: Step by Step
Holding capacity depends on soil type and the rated hardware used. There’s no universal spec for a buried tire, and we’re not going to pretend otherwise.
- Dig your pit perpendicular to the pull direction, angled slightly away from the vehicle, so the tire’s face resists the load head-on rather than getting dragged sideways through the dirt.
- Keep the front wall of the pit vertical. A sloped or crumbled front wall gives the tire less undisturbed soil to push against, which is the entire source of its holding power.
- Run a chain or strap through the tire (through the wheel opening, around the tread) with a shackle at the connection point, not a hook: a hook can shed the line if tension slacks mid-pull.
- Backfill and compact in stages, tamping as you go rather than dumping loose soil in all at once.
- Route the line out of the pit at a low angle and keep the connection point at or near ground level so the pull doesn’t lever the tire up and out.
Be honest with yourself about the labor. Forum accounts from experienced off-roaders describe burying a spare tire 4 to 6 feet deep in soft or saturated ground to get it to hold. One described a 4-by-6-foot pit in what he called “bottomless Florida muck.” Another put it plainly: by the time you’ve dug a hole that size, you may as well have dug the truck out directly. Treat the buried tire as a genuine last resort, not a shortcut.
Log Deadman Anchors: Sizing and Rigging
No manufacturer spec governs an improvised log anchor sized for a stuck 4x4 or UTV. What exists is engineering guidance built for industrial cable-logging loads, which we’re citing here as a reference point for the underlying principles, not as a vehicle-scale recommendation.
The USDA Forest Service, Oregon State University, and Oregon OSHA jointly publish a Deadman Anchor Quick Reference for heavy-duty rigging. Their specs, for context: a trench at least 5 feet deep, dug perpendicular to the pull with vertical walls, and a log at least 16 feet long and 18 inches in diameter (or several smaller logs bundled with a strap). That’s built for multi-ton yarding tension (well beyond what a stuck vehicle applies), but the installation logic scales down:
- Place the line in the trench with slack, lay the log above it, and loop the line over the log in the direction of pull.
- Backfill halfway and compact before tensioning, then backfill the rest.
- Don’t disturb the front wall of the trench once it’s cut. The same guide notes disturbing that wall reduces the anchor’s capacity: it’s the wall doing the holding, not the log.
- Piling extra soil or rock on top of the trench can add capacity, per the same source.
The guide’s own framing is worth repeating here: it’s general guidance only, and final anchor design should come from qualified personnel. That caveat applies even harder once you scale it down to a driveway log and a Saturday recovery. Once a log deadman is in the ground, check it: the same reference calls for inspecting a working deadman at least daily, watching for line movement or soil displacement, and reinstalling deeper with a lower cable angle or more logs if you see either.
How Deep Is Deep Enough? Why Soil Type Matters More Than a Number
There’s no depth number that works across all ground, and the data backs that up directly. Deadman Off-Road, which manufactures a commercial ground anchor plate, publishes a 2-foot minimum burial depth in their own installation instructions, but their testing shows just how much depth changes the outcome in identical soil: roughly 2,500 lb of holding capacity at 24 inches in soft sand, versus more than 6,000 lb at 36 inches in that same sand. In hardpack soil, they note 18 inches can match or beat that shallower sand figure. Their own internal testing recorded 8,050 lb in dune sand under specific conditions: a real number, but one they frame as dependent on depth, density, and pull angle, not a rating you can assume applies to your hole.
Pull angle matters too. Deadman Off-Road notes their anchor holds more when the pull comes from above the vehicle than from below it, worth factoring in on sloped terrain.
The underlying reason soil type dominates the math: soil is characterized by texture, moisture, and density, and those three properties are what an anchor is actually fighting against, per Oregon State University’s engineering guide on deadman anchors. Loose, dry sand gives up far more easily than compacted clay or hardpack at the same depth. If you’re unsure what you’re digging into, go deeper than the minimum: the data above says that’s rarely wasted effort.
Commercial Ground Anchors: What They Claim and What’s Sourced
Capacity claims vary by maker and soil. We’re citing each manufacturer’s own guidance where we could confirm it, and flagging plainly where we couldn’t.