The California bridge law chart in Vehicle Code Section 35551 sets the maximum weight allowed on any group of two or more consecutive axles based on the number of axles in the group and the distance between the outermost ones. The overall ceiling for most commercial vehicles is 80,000 pounds gross. Below that, the chart controls how much weight you can place on each axle group, and a separate statute caps individual axles at 20,000 pounds.
The California Bridge Law Weight Chart
The table below reproduces the key reference points from Vehicle Code Section 35551. Distances are in feet between the extreme axles of the group; weights are the maximum permitted in pounds.1California Legislative Information. California Vehicle Code 35551 – Axle Limits
| Distance (ft) | 2 Axles | 3 Axles | 4 Axles | 5 Axles | 6 Axles |
|---|---|---|---|---|---|
| 4 | 34,000 | 34,000 | 34,000 | 34,000 | 34,000 |
| 8 | 34,000 | 34,000 | 34,000 | 34,000 | 34,000 |
| 10 | 40,000 | 43,500 | 43,500 | 43,500 | 43,500 |
| 15 | 40,000 | 47,000 | 52,000 | 52,000 | 52,000 |
| 20 | 40,000 | 51,000 | 55,500 | 55,500 | 55,500 |
| 25 | 40,000 | 54,500 | 58,500 | 58,500 | 58,500 |
| 30 | 40,000 | 58,500 | 62,000 | 62,000 | 62,000 |
| 35 | 40,000 | 60,000 | 65,500 | 65,500 | 65,500 |
| 40 | 40,000 | 60,000 | 68,500 | 70,000 | 70,000 |
| 45 | 40,000 | 60,000 | 72,000 | 76,000 | 80,000 |
| 50 | 40,000 | 60,000 | 75,500 | 79,000 | 80,000 |
| 51+ | 40,000 | 60,000 | 76,000+ | 80,000 | 80,000 |
How To Read the Chart
Find the row for the distance between the first and last axle of the group you are checking, then read across to the column matching the number of axles in that group. The value is the maximum combined weight those axles can put on the road.
A few patterns will save you time. For any group with axles spaced between 4 and 8 feet apart, the cap is 34,000 pounds regardless of how many axles the group contains, which is why that number surfaces so often in tandem-axle enforcement. Two-axle groups top out at 40,000 pounds once spacing exceeds 8 feet, and three-axle groups top out at 60,000 pounds at 32 feet and beyond. Five-axle groups reach the 80,000-pound gross ceiling at 51 feet; six-axle groups get there at 45 feet because the extra axle spreads the load.1California Legislative Information. California Vehicle Code 35551 – Axle Limits
The chart rests on the Federal Bridge Formula, which the Federal Highway Administration uses to keep concentrated loads from overstressing bridge decks and pavement. More axles and greater spacing allow more weight because the load spreads farther.2Federal Highway Administration. Bridge Formula Weights
Single Axle and Per-Wheel Caps
The group chart is only half the picture. Vehicle Code Section 35550 imposes a separate ceiling on every individual axle: no single axle may carry more than 20,000 pounds, and no single wheel or set of wheels on one end of an axle may exceed 10,500 pounds.3California Legislative Information. California Code VEH 35550 – Axle Limits
Both limits apply at the same time. Even where the group chart would allow a higher combined weight, no single axle inside that group is permitted to exceed 20,000 pounds. Check the group total against 35551 and check each axle against 35550 before you leave the yard.
Trailer Combinations Use a Different Table
If your vehicle is a combination that includes a trailer or semitrailer, the numbers change. Vehicle Code Section 35551.5 governs these combinations, dropping the single-axle cap to 18,000 pounds and the per-wheel cap to 9,500 pounds. The front steering axle of the tractor is the exception at up to 12,500 pounds.4Caltrans. Caltrans – Weight Limitation
Section 35551.5 also has its own group axle table with a lower overall cap of 76,800 pounds at 56 feet or more.5California Legislative Information. California Code VEH – Axle Limits A five-axle tractor-semitrailer runs against these numbers, not the more generous ones in the main 35551 table.
Weight Allowances That Push Above the Chart
Two categories of equipment let you legally exceed the numbers above. Under Vehicle Code Section 35559, the power unit of a qualifying near-zero or zero-emission truck can exceed normal gross weight limits by up to 2,000 pounds, taking the maximum gross to 82,000 pounds. If a combination has more than one power unit, that 2,000 pounds can be split but not enlarged.5California Legislative Information. California Code VEH – Axle Limits The allowance offsets the added weight of batteries and natural gas fuel systems. Federal law provides a comparable 2,000-pound allowance on the Interstate system under 23 U.S.C. 127(s).6Alternative Fuels Data Center. Natural Gas Vehicle (NGV) and Electric Vehicle (EV) Weight Exemption
Vehicles fitted with an auxiliary power unit or other idle reduction technology can exceed gross, single, tandem, and bridge formula limits by up to 550 pounds under federal law. The driver has to carry proof of the APU’s weight and be able to show that the unit is fully functional if an officer asks.7Alternative Fuels Data Center. Idle Reduction and Alternative Fuel Vehicle Weight Exemption
When You Need an Overweight Permit
Loads that will exceed 80,000 pounds gross, or that will exceed any axle limit, require a special transportation permit from Caltrans before the truck moves. Permits are available only for loads that are reasonably non-divisible, meaning splitting them would destroy their value or function.8Caltrans. General Provisions Relating to Oversize/Overweight Transportation Permits Cost or convenience of splitting a load is not a basis for a permit. Caltrans issues single-trip permits for one movement and annual permits for repeated movements within defined parameters, with certain restricted routes closed to annual permit holders.9Caltrans. Transportation Permits (Oversize/Overweight Vehicles)
Penalties for Running Over the Limits
Overweight fines under Vehicle Code Section 42030 climb on a graduated scale tied to how far over the legal weight you are:
- 1 to 1,000 lbs over: $20 base fine
- 1,001 to 1,500 lbs: $30
- 1,501 to 2,000 lbs: $40
- 2,001 to 2,500 lbs: $55
- 2,501 to 3,000 lbs: $85
- 3,001 to 3,500 lbs: $105
- 3,501 to 4,000 lbs: $125
- 4,001 to 4,500 lbs: $145
- 4,501 to 5,000 lbs: $175
- 5,001 to 6,000 lbs: $0.04 per pound over the limit
- 6,001 to 7,000 lbs: $0.06 per pound
- 7,001 to 8,000 lbs: $0.08 per pound
- 8,001 to 10,000 lbs: $0.15 per pound
- 10,001 lbs and over: $0.20 per pound
These are base fines. Court penalty assessments and surcharges routinely multiply the final amount several times. When the excess weight tops 4,500 pounds, the violation is charged as a misdemeanor rather than an infraction, which opens the door to county jail time on top of the fine.
Violating the terms of an existing overweight permit is a separate offense with a fine of up to $500, potential jail time of up to six months, and an added per-pound fine on any weight above the permit’s authorized amount.10California Legislative Information. California Vehicle Code 35784 – Penalties An overweight stop also holds up the load until enough cargo is offloaded to bring the truck legal, and repeat violations feed into compliance records that affect future permit eligibility.