- What is a soft shackle? A loop of HMPE rope with a button knot on one end. It locks under load, comes undone by hand, and replaces a steel bow shackle.
- It connects things: rope to rope, rope to sling, winch line to a rated recovery point. That's the whole job.
- It's not weak. The store's published chart puts a 1/2-inch soft shackle at 62,500 lbs minimum breaking strength. A 5/16 is 37,100 lbs.
- No metal means no chunk of steel in the air if a connection lets go, and no gouged paint when it swings.
- Rick keeps one on the truck all the time — and in this episode he put it back and grabbed a hard shackle. We'll get to why.
1. It's a Piece of Rope. That's the Trick.
A soft shackle is a piece of rope. One end is spliced into a small eye. The other is tied into a fat button knot. You push the knot through the eye, the loop closes, and the harder you pull the tighter it holds. When the load comes off, you pop the knot back out with your fingers. No pin, no threads, no wrench.
That's the whole device, and it's stout. It'll hold more than almost anything steel in your toolbox.
It feels wrong the first time. You're holding two ounces of rope and you're about to put a truck on it. Then you watch it close up on itself under load, and that's a satisfying thing to see.
2. What It's Made Of
The fibre is HMPE — high modulus polyethylene. Same family as modern synthetic winch line, and pound for pound it outpulls steel. The store says the fibre is "pre-coated for UV, water, and abrasion protection," which decides whether you're still using it in five years or binning it in two.
Over the body there's a chafe sleeve — a second layer that takes the rubbing so the load-bearing fibre underneath doesn't. On the Double Loop that sleeve runs 36 inches. So what actually kills synthetic rigging? Abrasion, not load. Almost nobody breaks a soft shackle by overloading it. They wear it out on a frame rail.
"HMPE synthetic fiber is pre-coated for UV, water, and abrasion protection so this soft-shackle will last a very long time as long as you don't swear at it too much, we can't protect its feelings with a coating."— "Double Loop" Soft Shackle product page, murphysdiesel.com
3. What You Actually Use It For
A soft shackle connects. That's it — everything else is a variation:
- Rope eye to rope eye — joining two ropes, or a rope to a sling.
- Rope to a rated recovery point — the eye on your kinetic rope to the hitch point on the truck.
- Winch line to whatever it has to pull on — a sling, a ring, a recovery point.
- Sling to sling — building a longer reach out of what's already in the bag.
Two things make it better than steel here. First: there's nothing hard in it. Swing a bow shackle into a fender at the end of a rope and you've got a body shop bill. Swing a soft shackle and you've got a noise.
Second: if a connection lets go, there's no chunk of metal launched down the line. BFGoodrich's 4x4 driving guide puts it about as plainly as it can be put — never connect two straps or ropes with a shackle, because "if the shackle breaks, it can fly like a bullet and cause serious injury."[1] Soft rigging takes that particular projectile out of the equation.
4. Why Rick Keeps One Handy
The M939 episode isn't a recovery at all. It's a 5-ton 6x6 that hasn't run in fifteen years, sitting in Scottsdale, and the job is getting it home. Rick is loading spare tires before he even leaves, because the rubber on it is done and the truck has about 200 miles to cover.
He's digging through a pile of spares, finds one with a rip in the sidewall, pulls it back out. Two good ones, maybe. Then, in the middle of that:
"They just got to make it about 200 miles, folks. It's why I always keep a Yankum soft shackle handy."— An Old Blind Man Gave Me This Military Truck… Will It Start?
Notice what he didn't say. Not that he was about to use one. That he keeps one handy. That's the real argument, and it's a boring one: it weighs nothing, takes no room, and the day you need a connector you won't be anywhere convenient.
Later he does rig up, hoisting a spare tire and then the fuel tank back into the truck with the Freedom 550's winch. His line for it: "Never leave home without your Wrecker Rick shackle and sling."
5. How Strong It Is for Its Size
The store's published minimum breaking strengths for the Double Loop, in the standard single-loop configuration:
| Diameter | MBS, standard configuration | Pair it with |
|---|---|---|
| 5/16" | 37,100 lbs | 3/4" kinetic rope · 5/16" winch line |
| 7/16" | 45,500 lbs | 7/8" and 1" kinetic rope · 3/8" and 7/16" winch line |
| 1/2" | 62,500 lbs | 1-1/4" ropes · 1/2" winch line |
Look at that middle row again. A 7/16-inch piece of rope you can coil in your palm, published at 45,500 lbs. That's the number that converts people.
Two cautions, and they aren't fine print. MBS is a breaking strength, not a working load — where a new shackle comes apart. You never design a pull near it. And it only holds for a shackle in good order: right size, rigged right, sleeve intact.
6. Standard or Double Loop?
The difference is length. The store puts the Double Loop at 20 inches with the loop closed and 40 inches open, which is about twice a standard soft shackle.
That buys you two things. Reach, so you can get a hand and a connector under a stuck rig and onto a point you can barely see. And strength — you can loop it back around the connection point, double it up, and the store says that "will nearly double the strength of the soft shackle." Not bad for a knot.
20 inches closed, 40 inches open, with a 36-inch chafe sleeve. Made by Yankum Ropes. Three diameters — 5/16, 7/16 and 1/2 inch — in red, black or hi-vis yellow. Doubles around a connection point for close to twice the standard strength.
Want a shorter, plainer one? The Murphys Diesel Recovery Kit ships with two 7/16-inch soft shackles already in the bag.
The long one. Reach for awkward points, or double it up for close to twice the strength. 5/16, 7/16 or 1/2 inch.
1-inch by 30-foot kinetic rope, two 7/16-inch slings, two 7/16-inch soft shackles, roll-top bag.
Pins into a 2-inch receiver. 13,200 lbs WLL at a 5:1 factor of safety, shaped to take soft shackles without chafing.
7. The Day It Was the Wrong Tool
Half an hour into the same episode, Rick has the winch line run out to lift a spare off a rack and swing the fuel tank back into the truck. He rigs it. Then he stops and calls it:
"All right, folks. Change of plans. We're going to use a hard shackle 'cause the soft shackle's too long."
That's a man with a drawer full of soft shackles reaching for steel on camera, because the lift had no room for 20 inches of connector. The length that gets you under a stuck truck is dead space on a short hoist.
So carry both. Soft shackles for connecting rope and rigging. A hard shackle for when the connection has to be tight and short. Anybody telling you one replaces the other hasn't rigged enough jobs.
The shackle is a small part of a bigger system. The system is what hurts people.
- Size it to the line, not to what's nearest. The chart pairs each diameter with a rope and winch line size. A mismatched shackle is a weak link you installed without knowing it.
- Anchor to a rated recovery point. BFGoodrich: "DO NOT attach a strap to a tow ball or bumper hitch. These are not rated for recovery and can break off under load."[1] That's what a hitch receiver recovery point is for.
- Pull in line. Same source: "DO NOT put side loads on recovery points, always pull in line with the vehicle."[1] The hitch point's own warning says the same, and adds that a side pull can tip a vehicle over.
- Don't join two ropes with a metal shackle. "If the shackle breaks, it can fly like a bullet."[1] This is the job a soft shackle exists for.
- Inspect the sleeve, then the fibre. A chafe sleeve worn through to the load-bearing fibre means that shackle is finished, whatever the label says.
- Gloves on. "Do not winch without gloves."[1]
Sources
- BFGoodrich Tires, "4x4 Driving Guide — Recovery Techniques." Every quote above confirmed verbatim, fetched 2026-09-19. bfgoodrichtires.com/auto/learn/4x4-driving-guide/recovery-techniques
- "Double Loop" Soft Shackle product page — the size chart, dimensions, chafe sleeve, coating and prices. Fetched 2026-09-19. murphysdiesel.com/products/double-loop-soft-shackle
Carry One Before You Need One
Two ounces of rope that will hold a truck, won't mark a panel, and won't turn into a projectile. Own one for the recovery you aren't planning.