A snapped chain under load doesn't warn you first — it drops the vehicle, whips back at highway speed, or blows a binder off an anchor point with no sound to tell you it's coming, and the only thing standing between that outcome and a clean haul is knowing the chain grade working load limit chart before you hook up. Grade 70 transport chain in 3/8-inch diameter carries a 6,600-pound working load limit, the baseline most car haulers and flatbed crews rig around in 2026, while Grade 100 and Grade 120 alloy chain push past 8,800 and 11,300 pounds in the same diameter when a heavier job demands more margin.
- Chain grade working load limit chart: Grade 70 (3/8-inch) rates 6,600 lbs WLL — the minimum most DOT-regulated cargo securement runs on in 2026.
- Grade 120 alloy chain nearly doubles Grade 70, rating 11,300 lbs WLL at the same 3/8-inch diameter.
- Grade 30 proof coil chain (2,650 lbs WLL) is not built or rated for DOT load securement — don't tie freight down with it.
- WLL figures assume new chain in a straight pull; wear, bent links, and angled rigging cut real-world capacity below these numbers.
Why This Chart Matters
A working load limit isn't a suggestion — it's the manufacturer's ceiling for repeated use on a moving vehicle, and every grade stamped into a link carries a different number even when the diameter looks identical from across the yard. Guessing a grade off memory, or grabbing whatever chain is coiled in the truck box, is how operators end up under-rated on a DOT roadside inspection or, worse, over-torquing a binder against a chain that can't take it.
The chart below breaks out working load limit by grade at 3/8-inch diameter, the size most common on car-hauler axle chains and flatbed tie-downs, so you can match the number on the tag to the number the job actually requires in 2026.
Chain Grade Working Load Limit Chart (2026)
The short answer: at 3/8-inch diameter, working load limit runs from 2,650 lbs on Grade 30 proof coil up to 11,300 lbs on Grade 120 alloy chain, with Grade 70 transport chain sitting at 6,600 lbs as the industry's DOT-accepted floor.
| Chain Grade | Classification | WLL — 3/8" Diameter | Typical Use |
|---|---|---|---|
| Grade 30 | Proof Coil | 2,650 lbs | Light utility — not DOT-rated for cargo securement |
| Grade 43 | High Test | 5,400 lbs | General towing, farm and logging chain |
| Grade 70 | Transport | 6,600 lbs | DOT cargo securement, flatbed and car-hauler tie-down |
| Grade 80 | Alloy | 7,100 lbs | Overhead rigging, heavier vehicle recovery |
| Grade 100 | Alloy | 8,800 lbs | Heavy equipment and machinery recovery |
| Grade 120 | Alloy | 11,300 lbs | Maximum-rated rigging — oilfield, crane, heavy haul |
| All Grades | — | 6,975 lbs avg | Reader's yardstick across all six common grades |
Grade 120 alloy chain leads this chart at 11,300 lbs WLL for 3/8-inch diameter — 4.3 times the rating of Grade 30 proof coil, which trails at 2,650 lbs and falls well short of what most commercial hauling actually requires. Grade 70 and Grade 80 sit in the middle, which is exactly why they show up most often on flatbed decks and rollback beds: enough margin for everyday loads without paying for alloy-grade capacity you don't need.
These figures reflect standard manufacturer working load limit ratings published for 3/8-inch chain, the size most common in flatbed and car-hauler rigging, with each grade's WLL set against its own safety factor relative to breaking strength. One limitation worth naming: WLL assumes new, undamaged chain in a straight pull — a worn link, a bent connector, heat exposure, or an angled rig all pull real capacity below the number stamped on the tag.
How to Use These Benchmarks
- If your load falls under DOT cargo securement rules, Grade 70 transport chain is your floor — Grade 30 and Grade 43 don't qualify no matter how new they look. The VULCAN chain and binder kit rated at 6,600 lbs is built to that exact spec.
- Step up to Grade 80 or Grade 100 when securing equipment over 10,000 lbs, or when a load shifts more weight onto fewer chain runs than the job originally planned for.
- Match your binder's rating to the chain grade, not the other way around — an under-rated binder on a Grade 80 chain is the weak link in the system, and it's the one that fails first.
- Recalculate aggregate WLL every time you add or remove a chain run. Federal cargo securement math requires total WLL across all tie-downs to equal at least half the cargo's weight, and that math changes the second your rigging does.
Compatibility: Matching Chain Grade to Binders, Hooks, and DOT Rules
Chain grade only tells half the story — the connectors on each end have to carry the same rating or the chain's WLL is meaningless. A Grade 80 alloy tow chain with forged long J-hook, rated 7,100 lbs only holds that number if the hook, the binder, and every link in the run are rated the same or higher; mixing a Grade 100 chain with a Grade 70 binder drags the whole assembly's effective limit down to the weakest component.
Diameter matters just as much as grade when you're swapping equipment between trucks. A 1/2-inch Grade 70 chain commonly rates around 11,300 lbs WLL — matching a 3/8-inch Grade 120 chain pound for pound — so a fleet standardizing on one diameter across mixed grades needs the chart in front of them, not a guess based on how thick a link feels in the hand.
DOT cargo securement rules (49 CFR 393.100-393.136) set the floor most commercial haulers rig to in 2026: aggregate WLL across all tie-downs must equal at least half the cargo's weight, and that's the regulatory reason Grade 70 became the default transport grade instead of Grade 30 or 43.
Safety and Inspection Before Every Haul
A working load limit only holds if the chain that carries it is inspected before it goes back to work — stretched links, nicks, gouges, or a bent connector all drop real capacity below the rated number even when the tag still reads Grade 70 or Grade 80. Crews running heavier hauls should walk through how to load bind with chain binders safely before tensioning against any chain grade near its rated limit, since over-torquing a binder is one of the fastest ways to turn a rated chain into a liability.
Check every link for wear at the same points each time — chain wears fastest where it wraps a hook or cleat, not in the straight runs — and pull any chain showing more than 10% reduction in link diameter from service immediately.
Maintenance and Care
Store chain dry and off concrete floors to slow rust, since surface corrosion eats into the cross-section that the working load limit was calculated against in the first place. Rinse road salt off after winter hauls, and re-inspect anything that's sat wet for more than a day before it goes back on a load.
A chain that's rusted through even one link no longer carries the WLL printed on its original tag, regardless of grade — replace the run rather than gamble on a number that no longer applies.
FAQ
What is the working load limit for Grade 70 chain?
Grade 70 transport chain in 3/8-inch diameter has a working load limit of 6,600 lbs in 2026. It's the minimum grade most operators use to meet DOT cargo securement rules.
What's the difference between Grade 70 and Grade 80 chain?
Grade 70 (transport chain) rates 6,600 lbs WLL at 3/8-inch diameter, while Grade 80 (alloy chain) rates 7,100 lbs at the same diameter. Grade 80 is heat-treated alloy steel, giving it more capacity per link than Grade 70's carbon steel.
How much weight can 3/8-inch chain hold?
It depends entirely on grade: 3/8-inch chain ranges from 2,650 lbs WLL on Grade 30 up to 11,300 lbs on Grade 120. Always check the grade stamp, not just the diameter.
Is Grade 100 chain stronger than Grade 80?
Yes — Grade 100 alloy chain rates 8,800 lbs WLL at 3/8-inch diameter versus 7,100 lbs for Grade 80. Grade 100 is typically reserved for heavy equipment recovery rather than everyday tie-down work.
What chain grade does DOT require for load securement?
Federal cargo securement rules (49 CFR 393.100-393.136) require aggregate working load limit equal to at least half the cargo's weight, and Grade 70 transport chain is the commonly accepted minimum grade used to meet it. Grade 30 and Grade 43 chain don't qualify.
Can you mix chain grades on the same load?
You shouldn't. Mixing grades drops the whole rigging assembly's effective working load limit to the rating of its weakest link, binder, or hook, regardless of what the strongest component is rated for.
How is chain working load limit calculated?
Manufacturers set WLL well below a chain's actual breaking strength, applying a safety factor specific to each grade. That's why WLL, not breaking strength, is the number stamped on tags and referenced in DOT regulations.
Does chain diameter matter more than grade?
Both matter together. A 1/2-inch Grade 70 chain rates close to 11,300 lbs WLL, matching a 3/8-inch Grade 120 chain, so diameter and grade both need checking before you assume two chains are interchangeable.
One Last Thing
The detail most operators miss: a 1/2-inch Grade 70 chain and a 3/8-inch Grade 120 chain land on nearly the same working load limit, around 11,300 lbs, despite one being a full grade lower. Grade alone doesn't tell you what a chain can hold — diameter and grade have to be read together, every time, before that chain gets rigged to a load in 2026.
Shop the full line of Grade 70 and Grade 80 chain, binders, and tie-down hardware built to these exact working load limits, and check the chart above before your next haul instead of after.