Size and Weight Limits
(207) 624-9000 ext. 52134

Gross Weight Limits

Maine General Law

Maine's General Law gross weight limit applies to the following highways:

Interstate 95 from the New Hampshire State Line to the southern terminus of the Maine Turnpike;
The Maine Turnpike (designated Interstate 95);
All non-Interstate highways.

Maine's General Law provides that the total weight of a vehicle or combination of vehicles, plus their load, is limited by the number of axles to:

Table 1 - General Law Gross Weight Limits
2 Axles	..........34,000 pounds
3 Axles	..........54,000 pounds
4 Axles	..........69,000 pounds *
5 Axles	..........80,000 pounds
6 Axles	..........100,000 pounds **

*Also applies to all single unit vehicles over 4 axles.

**Applies only to a combination vehicle consisting of a 3 axle truck tractor towing a triaxle semitrailer unit that is operating on the General Law highways listed above. The 80,000 pound limit applies to all other combination vehicles over 4 axles, except for certain vehicles carrying special commodities which are allowed additional weight tolerances. (53 foot semitrailer vehicles are restricted to 80,000 pounds GVW on the Maine Turnpike.)

Interstate Highway System

For operation on the Interstate Highway System, excluding those segments of the Interstate Highway System listed above, the weight of the vehicle or combinations of vehicles, plus their load, is limited by Bridge Formula B, modified. In addition, the Bridge Formula also limits the total weight of any group of consecutive axles of a vehicle or combination of vehicles according to the distance between the centers of the extreme axles in a group. The greatest load allowed is 80,000 pounds.

The following are exceptions to the use of the Bridge Formula on the Interstate System:

Single axles are limited to 20,000 pounds for vehicles over 73,280 pounds GVW, and 22,000 pounds for vehicles 73,280 pounds GVW or less.
Tandem axles are limited to 34,000 pounds.
Two consecutive tandem axles may carry 34,000 pounds each if there are at least 36 feet between centers of extreme axles.
All 3 axle trucks with brakes on the wheels of all axles may be operated with a gross weight of 48,000 pounds if the distance between extreme axles is at least 16 feet when hauling construction materials or 18 feet when hauling forest products or hauling raw ore from mine or quarry to place of processing.

Axle Weight Limits

Groups of closely spaced axles are treated as follows:

Axles whose centers are less than 4 feet apart shall be considered a single axle unit.
A single axle whose center is closer than 10 feet, or if it is a steering axle 9 feet, to a triaxle unit shall be considered part of that triaxle and not add to the allowable load capacity of that triaxle unit.

The axle weights and distance limits for axle units are:

Table 2 - Axle Unit Weight Limits
	Single Axle	Tandem Axle	Triaxle
Interstate	22,000 lbs (1)	34,000 lbs	(2)
Non Interstate (3) - General	22,400 lbs	38,000 lbs (4)	48,000 lbs (5)
Non Interstate (3) - Special Products	24,200 lbs	46,000 lbs (6)	54,000 lbs (7)

(1) 20,000 pounds for GVW over 73,280 pounds;
(2) Controlled by Bridge Formula (see Table 3 below)
(3) For the following roads: Interstate 95 from the New Hampshire State Line to the southern terminus of the Maine Turnpike, the Maine Turnpike (designated Interstate 95 and 495) and all non-Interstate highways;
(4) Exceptions - 41,000 lbs on a six axle combination;
(5) Exceptions - 50,000 lbs on a six axle combination;
(6) 44,000 pounds tandem limit for 5 or more axle combinations.
(7) 64,000 pounds for 4 axle single unit vehicles hauling forest products.
All loads are limited to 600 pounds per inch of tire width, manufacturer's rating, excepting farm trucks transporting potatoes directly from the field to the place of storage or to a processing facility during the potato harvesting season.

Table 3 - Interstate Axle Group "Bridge Formula" Weight Limits
Distance (FT) Between Centers of Extreme Axles in Axle Group	Gross Weight Limit On Any Group of Consecutive Axles
	2 Axles	3 Axles	4 Axles	5 Axles	6 Axles	7 Axles
4..................................	34,000
5..................................	34,000
6..................................	34,000
7..................................	34,000		AXLE	GROUPS	IN
8..................................	34,000	34,000
More than 8.................	38,000	42,000		THESE	SPACINGS
9..................................	39,000	43,000
10................................	40,000	43,500			IMPRACTICAL
11................................	41,000*	44,500
12................................	42,000*	45,000	50,000
13................................	43,000*	46,000	50,500
14................................	44,000*	46,500	51,500
15..............................................		47,500	52,000
16..............................................		48,000	52,500	58,000
17..............................................		49,000	53,500	58,500
18..............................................		49,500	54,000	59,500
19..............................................		50,500	54,500	60,000
20..............................................		51,000	55,500	60,500	66,000
21..............................................		52,000	56,000	61,000	66,500
22..............................................		52,500	56,500	62,000	67,000
23..............................................		53,500	57,500	62,500	68,000
24..............................................		54,000	58,000	63,000	68,500	74,000
25..............................................		55,000	58,500	63,500	69,000	74,500
26..............................................		55,500	59,500	64,500	69,500	75,000
27..............................................		56,500	60,000	65,000	70,000	76,000
28..............................................		57,000	60,500	65,500	71,000	76,500
29..............................................		58,000	61,500	66,000	71,500	77,000
30..............................................		58,500	62,000	67,000	72,000	77,500
31..............................................		59,000	62,500	67,500	72,500	78,000
32..............................................		60,000	63,500	68,000	73,000	78,500
33............................................................			64,000	68,500	74,000	79,500
34............................................................			64,500	69,500	74,500	80,000
35............................................................			65,500	70,000	75,000
36............................................................			66,000**	70,500	75,500
37............................................................			66,500**	71,000	76,000
38............................................................			67,500**	72,000	,77,000
39............................................................			68,000	72,500	77,500
40............................................................			68,500	73,000	78,000
41............................................................			69,500	73,500	78,500
42............................................................			70,000	74,500	79,000
43............................................................			71,000	75,000	80,000
44............................................................			71,500	75,500
45............................................................			72,000	76,000
46............................................................				77,000
47............................................................			Greater	77,500
48............................................................			Loads	78,000
49............................................................			Not	78,500
50............................................................			Practical	79,500
51............................................................				80,000

*40,000 lbs. if GVW is 73,280 lbs. or more. ** If two tandems, 68,000 lbs.

Tolerances and permits (Excluding the Interstate System)

General Tolerance

Provided that gross, axle, and tire limits are not exceeded, vehicles may operate at a gross weight exceeding the current registration by the greater of 2 1/2 percent or 500 pounds.

A three axle truck tractor (not truck) and triaxle semitrailer combination vehicle (Special 6) may operate at a maximum of 100,000 pounds GVW if:

The vehicle is registered or apportioned for 100,000 pounds;
The distance* between extreme axles, excluding the steering axle, is at least 36 feet to the nearest foot;
*The 100,000 pound maximum GVW shall be reduced 2,000 pounds for each foot this distance is less than 36 feet, to the nearest foot.
The minimum distance between steering axle and the first axle of the tandem is at least 10 feet to the nearest foot;
The maximum weight shall not exceed 41,000 pounds on the tandem axle and 50,000 pounds on the triaxle;
For all vehicles manufactured, modified, or retrofitted with liftable or variable load suspension axles after October 30, 1991, such axles are permitted only under the following conditions:
- Only one liftable or variable load axle may be present on the truck tractor unit, and such axle must be legally part of the tandem axle group.
- Only one liftable or variable load axle may be present on the semitrailer unit, and such axle must be legally part of the triaxle group.
- The axle weight rating of the lift axle must conform to the expected loading of the suspension and be at least 20,000 pounds or more.

Special Limits for Certain Commodities

While actively engaged in the exclusive transport of the commodities listed below, vehicles will be allowed special weight tolerances.

The special weight tolerances are:

10% over the maximum gross weights (up to 80,000 pounds) listed in Table 1;
85,000 pounds GVW for certain six axle single unit trucks carrying only forest products;
94,000 pounds GVW for certain four axle single unit truck trailer combination vehicles;
100,000 pounds GVW for combination vehicles consisting of a three-axle truck-tractor (not truck) with triaxle semitrailer that is registered or apportioned for at least 90,000 pounds GVW; and
Axle weight limits: See Table 2.

Restrictions include:

Wheelbase reductions for 4 or more axle combinations;
600 pounds per inch of tire width, manufacturer's rating;
Unless otherwise indicated in this section, the vehicle must be registered or apportioned for the maximum legal weight allowed for that vehicle configuration under Maine law;
For operation at 100,000 pounds gross weight, the distance between the extreme axles of the vehicle, excluding the steering axle, must be at least 32 feet to the nearest foot.

The vehicle must be loaded entirely with the following commodities:

Materials or unset concrete intended for highway construction and carried in dump or transit mix trucks;
Manufacturer's concrete products;
Raw ore from mine or quarry to place of processing;
Unprocessed milk;
Refrigerated products when they constitute the majority of products carried in a sealed vehicle;
Building materials that absorb moisture during delivery originating and terminating within the State;
Incinerator ash;
Unconsolidated rock materials, including limestone, and: bark; pulpwood; firewood; logs; sawed lumber; bolts; soils; dimension lumber; road salt; solid waste; farm produce; sawdust; and wood chips.

A four axle single unit truck, two axle trailer combination vehicle carrying the commodities listed above may operate at the maximum gross vehicle weight of 94,000 pounds under either of the following conditions:

The trailer unit is registered for at least 28,000 pounds gross weight and the combined registered weight for the truck and trailer is at least 94,000 pounds gross weight; or
The truck is registered for at least 94,000 pounds.

Other restrictions apply. Contact the Bureau of Motor Vehicles, Motor Carrier Services Office for further information.

Projecting Objects & Trailers

Vehicles carrying objects that project more than 4 feet from the rear of the vehicle must, during the period of 1/2 hour after sunset to 1/2 hour before sunrise, carry a red light at or near the rear end of the projecting objects. At all other times, the vehicle must carry a clean red cloth of the dimensions 12 x 12 inches attached at or near the end of the projecting object.

During the hours when lights are required, a vehicle carrying logs that project more than 4 feet from the rear of the vehicle is required to display a red reflector or to paint reflectorized paint on the end of the log projecting furthest to the rear. The reflector or reflectorized paint must be properly maintained, and must be located and be the size which is sufficient to reflect at night on an unlighted highway the undimmed headlights of a vehicle approaching the rear of the vehicle from a distance of at least 200 feet.

A load must be covered or otherwise secured or confined to prevent any portion of the load from falling from or spilling out of the vehicle.

Trailers, semitrailers, or vehicles being towed must, in addition to the tow bar or coupling device, have a safety chain or steel cable made of not less than 1/4 inch wire so attached as to prevent breakaway from the towing vehicle. (This requirement does not apply to truck tractor and semitrailer units equipped with a fifth wheel mechanism.)

Trailers that are wider then the towing vehicle must be equipped with reflective material or a lamp on each front corner that is visible to oncoming traffic.

Questions or comments can be sent to the Overlimit Permits Unit at: overpermits@maine.gov

AGENCY INFORMATION

Size and Weight Limits (207) 624-9000 ext. 52134