Machinery has no single freight class — density decides, machine by machine. General machinery ships under NMFC 133300 (Machinery or Machines, NOI), and since July 19, 2025 it rates on the standardized 13-tier density scale. In practice most crated industrial machines land at 8–15 lb/ft³ — class 100–85. Cast-iron machine tools push 15–22 lb/ft³ and drop to class 70; open-frame stainless packaging lines float at 4–8 lb/ft³ and climb to class 125–175. The class is arithmetic you can run before you book: dims, weight, density, chart.
What freight class is machinery?
Machinery spans nearly the whole chart, which is why "what class is a machine?" has no one answer — but each machine type clusters tightly once you think in shipped density. Here's where common equipment actually lands, as tendered (machine plus skid or crate):
| Machinery, as tendered | Typical shipped density | Density-scale class |
|---|---|---|
| Dies, molds, castings, press tooling (low crates) | 35+ lb/ft³ | 55–50 |
| Engines, gearboxes, pumps (palletized) | 15–35 lb/ft³ | 70–60 |
| Machine tools: lathes, mills, saws (skidded or crated) | 12–22 lb/ft³ | 85–70 |
| Air compressors, generator sets | 8–15 lb/ft³ | 100–85 |
| Packaging & food-processing machinery (stainless, open frame) | 4–8 lb/ft³ | 175–125 |
| Fabricated enclosures, hoppers, machine guarding | 1–4 lb/ft³ | 300–250 |
The pattern is metal-to-air ratio. A gearbox is nearly solid iron; a bagging machine is a stainless skeleton around empty process space. Broker guidance that "machinery runs class 85–300" is really describing that spread. Your machine's exact class comes from the four-step density calculation — measure the extreme dims of the handling unit, cube it, divide the weight, read the chart.
Crated vs skidded: does packaging change the class?
For decades the NMFC said yes, explicitly. Item 133300 carried two parallel density tables — one for machinery in boxes or crates, one for machinery on skids or otherwise exposed — and the skidded column always rated higher, pricing in the handling and damage risk of an uncrated machine. This is the version most old tariff sheets still quote (in force from 2021 until the July 2025 overhaul):
| Density (lb/ft³) | Boxed / crated | Skidded / not boxed |
|---|---|---|
| Less than 5 | 250 | 400 |
| 5 but less than 10 | 125 | 175 |
| 10 but less than 15 | 85 | 100 |
| 15 or greater | 65 | 77.5 |
Docket 2025-1 swept general machinery onto the single 13-tier density scale along with the rest of the industrial group — measured density as tendered now sets the class, and packaging shows up only through what it does to that density (classes like 77.5 don't even exist on the new scale). The strategy consequence is real: a crate adds both pounds and cubic feet, so it can push a machine either direction across a break. Older tariffs and FAK agreements may still print the two-column rules, so confirm the current item and class with your carrier before it hits the BOL — the background is in the 2025 NMFC changes, in plain English.
Worked example: one used knee mill, three ways
Same 2,000-lb Bridgeport-style knee mill, three ways of tendering it. Cube first — length × width × height in inches ÷ 1,728 — then weight ÷ cube:
| Configuration | Dims (in) | Weight | Cube | Density | Class |
|---|---|---|---|---|---|
| Bolted to skid, shrink-wrapped | 56 × 48 × 82 | 2,050 lb | 127.6 ft³ | 16.1 lb/ft³ | 70 |
| Full wood crate, built to standing height | 64 × 52 × 88 | 2,350 lb | 169.5 ft³ | 13.9 lb/ft³ | 85 |
| Crated, head rotated down & knee dropped | 64 × 52 × 72 | 2,350 lb | 138.7 ft³ | 16.9 lb/ft³ | 70 |
Row one: 56 × 48 × 82 = 220,416 in³ ÷ 1,728 = 127.6 ft³; 2,050 ÷ 127.6 = 16.1 lb/ft³ — the "15 but less than 22.5" tier, class 70. Row two crates the same machine and the class gets worse: the crate added 300 lb but 42 cubic feet, density fell to 13.9, and the shipment crossed the break at 15 into class 85.
Row three claws it back without giving up the crate. Rotating the head down and dropping the knee — ten minutes with a wrench on most mills — cuts the crate from 88 to 72 inches tall. Density lands at 16.9 lb/ft³ and the machine is back in class 70, fully boxed. That's the general machinery lesson: the billed rectangle is negotiable before pickup, never after. Check where your own load sits against the breaks with the density calculator.
How do you get machinery into a lower class?
- Shrink the rectangle before you build the crate. Fold or lower whatever folds, unbolt handwheels, levers, stacks and chutes, and pack them inside the crate or banded to the same skid. Carriers measure extreme dimensions of the handling unit — one protruding lever bills like a bigger machine.
- Crate snug, not roomy. Every inch of headroom is air you pay for. A crate sized to the folded machine, not the standing one, is often the difference of a full class tier, as in the worked example above.
- Put the weight to work. Shipping the vise, tooling, chuck or spare parts with the machine adds pounds to the same cube and pushes density up. Consolidate into one handling unit where it's safe to do so.
- Declare the real numbers. LTL terminals run dimensioners, and machinery is exactly the freight they flag: heavy, irregular, easy to under-declare. A reclass turns a clean invoice into base rate plus inspection fees — how class moves the rate shows what's at stake per tier.
- Skid vs crate is a business decision, not just a class decision. A bare machine on a skid is often denser, but exposed handwheels, ways and sheet-metal guards are what damage claims are made of — and if the machine is used, the liability math below says the claim may be nearly worthless.
Used machinery: the 10-cents-a-pound trap
Freight class doesn't care about age — a used mill cubes and weighs like a new one. Carrier liability cares enormously. Standard LTL tariffs cap liability for new goods at roughly $0.50–$25 per pound depending on class and carrier, but "articles other than new" — which is every used, reconditioned or customer-owned machine — are commonly capped at $0.10 per pound. The arithmetic is brutal: a 3,800-lb used machining center damaged in transit recovers at most about $380, whatever it's worth. On a $45,000 machine that's under one percent. Crating well is the first defense; the second is declaring the real value and buying cargo coverage, which typically prices from a few dollars per $1,000 of declared value — the math and the when-to-buy logic are in the freight insurance guide. Photograph the machine as it leaves, note any damage on the delivery receipt before signing, and never let "it's used anyway" talk you out of the crate.
When is a machine too big for LTL?
LTL works while a dock forklift can move the piece: single handling units beyond roughly 8 feet in a dimension or a few thousand pounds start drawing overlength fees, and somewhere past that the freight simply belongs on open deck. Broker-published 2026 figures put flatbed at about $2.12 per mile, step deck at $2.35 and RGN/lowboy at $3.40; typical moves price like an 8,000-lb skid steer going 300 miles at $900–$1,100, or a 12,000-lb mini excavator going 350 miles at $1,100–$1,400. Oversize pieces add permits at $50–$500+ per state. Below those thresholds, machinery is ordinary LTL freight that brokers quote anywhere from about $300 to $4,000+ depending on class, weight and lane — which brings it back to density: measure, cube, divide, and know your class before the carrier's dimensioner decides for you.