New Jersey truck weight limits
On Interstate highways in New Jersey, federal weight limits apply. Four checks decide whether your truck is legal — and the one that surprises most drivers is the Federal Bridge Formula, which can fail a truck that passes every other limit.
Federal limits on New Jersey Interstates
| Limit | Maximum | Applies to |
|---|---|---|
| Single axle | 20,000 lb | Any one axle |
| Tandem axle group | 34,000 lb | Axles 40–96 inches apart |
| Tridem axle group | governed by the bridge formula | 3 axles in a group (no flat federal cap) |
| Gross vehicle weight | 80,000 lb | The whole rig |
| Bridge formula | varies by spacing | Every group of 2+ axles |
The bridge formula check
L is the spacing in feet between the outer axles of a group, N the number of axles. A standard 5-axle rig at 51 ft is capped at 79,500 lb by this formula — under the 80,000 lb gross limit. Full explanation with worked examples.
New Jersey-specific rules
New Jersey is dense, and its weight law (N.J.S.A. 39:3-84) is as much about where you can drive as how heavy. On the Interstate, federal limits govern: 20,000 lb single axle, 34,000 lb tandem, 80,000 lb gross, plus the Federal Bridge Formula. Off the Interstate, New Jersey allows a 22,400 lb single axle (higher than the federal 20,000), a 34,000 lb tandem, and gross capped at 80,000 lb by an axle-spacing table. The bigger trap is route restrictions — the same statute bars trucks from many roads and confines through-trucks to designated truck routes / the National Network, with limited access off them.
New Jersey exceptions to the federal limits
New Jersey's limits (N.J.S.A. 39:3-84):
| Group | Non-Interstate | Interstate |
|---|---|---|
| Single axle | 22,400 lb | 20,000 lb |
| Tandem axle group | 34,000 lb | 34,000 lb |
| Two consecutive tandem sets | 68,000 lb combined | 68,000 lb combined |
| Maximum gross | 80,000 lb | 80,000 lb (bridge formula) |
- Gross is set by an axle-spacing table; the 80,000 lb cap holds on all roads.
- Route restrictions: § 39:3-84 confines trucks to designated routes and the National Network — running a prohibited route is a separate, fineable violation independent of weight.
- On Interstates, federal limits govern — the 22,400 lb single axle does not apply there.
Seasonal & designated-route rules in New Jersey
New Jersey does not run a statewide spring "frost law" program. The binding constraints are truck-route restrictions and posted-bridge/overpass limits — a very dense network of them. A posted bridge or overpass overrides the general limit, and low-clearance and weight-restricted structures are common on non-Interstate routes. Confirm your route is a legal truck route and clear of postings before you run it.
Overweight permits in New Jersey
Loads over the legal limits — or that need to leave the designated truck-route network — require an oversize/overweight permit from NJDOT (and Code 23 overweight registration through NJ MVC for certain vehicles), route-specific by bridge and pavement rating.
Fines & enforcement in New Jersey
Enforced by the New Jersey State Police at fixed scales and with portable/mobile enforcement. New Jersey fines both overweight and operating on a prohibited route (N.J.S.A. 39:3-84.3), so a route violation costs you even when the load is legal.
What dispatchers should check in New Jersey
- Route legality first — confirm the road is a designated truck route / National Network before weight; a prohibited-route ticket is separate from an overweight one.
- 22,400 lb single axle is non-Interstate only — on the Interstate it drops to the federal 20,000 lb.
- Posted bridges & overpasses — dense in NJ; a posting overrides the general limit.
- Interstate — federal 20,000 / 34,000 / 80,000 plus the bridge formula.
New Jersey truck weight — frequently asked questions
How much can a truck weigh in New Jersey?
On New Jersey Interstates the federal gross-weight limit is 80,000 lb, with a 20,000 lb single-axle limit, a 34,000 lb tandem limit and the Federal Bridge Formula. New Jersey sets its own limits on non-Interstate roads — see the New Jersey-specific rules on this page.
Does New Jersey follow federal truck weight limits?
On the Interstate system, yes — federal limits govern in every state. Off the Interstate, New Jersey applies its own axle, gross and permit rules, detailed on this page where they have been verified against the official state source.
What is the single-axle weight limit in New Jersey?
The federal single-axle limit of 20,000 lb applies on New Jersey Interstates. Some states set a different single-axle figure on non-Interstate roads — check the New Jersey-specific section above for the governing number.
What is the maximum tandem-axle weight in New Jersey?
On New Jersey Interstates the federal tandem limit is 34,000 lb. Several states allow a different tandem weight on non-Interstate roads — see the New Jersey exceptions above for the figure that governs.
Scaled heavy in New Jersey?
If the trailer tandems are over, the fix is usually a computed tandem slide, not unloading — see how sliding tandems shifts weight. And here's what an overweight ticket really costs before you decide to run it.
Run your scale-ticket weights through the federal and bridge-formula calculator in your browser. The full platform predicts axle loads from load placement before you load, computes the exact slide-to-legal fix, and applies New Jersey rules on top of the federal baseline.
Open the free calculatorOur calculator runs the federal single, tandem, gross and Bridge Formula checks in seconds. The full platform adds per-state limits, axle-load prediction and the slide-to-legal fix.
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