LEGAL TRUCK SIZE & WEIGHT
Summarized here is the new federal law regarding saddlemount (driveaway and towaway) combinations.
In Title 23, Code of Federal Regulations (CFR), Part 658, the Federal Highway Administration (FHWA) defines a saddlemount combination. The definition is copied below with bolding added.
A saddlemount combination is a combination of vehicles in which a truck or truck tractor tows one or more trucks or truck tractors, each connected by a saddle to the frame or fifth wheel of the vehicle in front of it. The saddle is a mechanism that connects the front axle of the towed vehicle to the frame or fifth wheel of the vehicle in front and functions like a fifth wheel kingpin connection. When two vehicles are towed in this manner the combination is called a double saddlemount combination. When three vehicles are towed in this manner, the combination is called a triple saddlemount combination. (23 CFR 658.5)
PREVIOUS FEDERAL LAW
Title 23, Code of Federal Regulations, Section 658.13 states (bolding added):
(e)(1)(iii) Driveaway saddlemount vehicle transporter combinations and driveaway saddlemount with fullmount vehicle transporter combinations are considered to be specialized equipment. No State shall impose an overall length limit of less than 75 feet on such combinations. This provision applies to saddlemount combinations with up to three saddlemounted vehicles. Such combinations may include one fullmount. Saddlemount combinations must also comply with the applicable safety regulations at 49 CFR 393.71.
NEW FEDERAL LAW
H.R. 3550, Section 4116, contains the language that changes the saddlemount length to 97 feet.
SAFETEA-LU SECTION 4141 -- DRIVEAWAY SADDLEMOUNT VEHICLES
The Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) was enacted August 10, 2005, as Public Law 109-59. SAFETEA-LU authorizes the Federal surface transportation programs for highways, highway safety, and transit for the 5-year period 2005-2009. Section 4141 makes the following changes in the United States Code (bolding added):
UNITED STATES CODE
(a) Definition.--Section 31111(a) title 49, United States Code (click on Title 49, Subtitle VI, Part B, Chapter 311, Subchapter II, Section 31111) is amended as follows (bolding added):
Sec. 31111. Length limitations
(a) Definitions.--In this section, the following definitions apply:
...(4) "Drive-away saddlemount with fullmount vehicle transporter combination.--The term 'drive-away saddlemount with fullmount vehicle transporter combination' means a vehicle combination designed and specifically used to tow up to 3 trucks or truck tractors, each connected by a saddle to the frame or fifth-wheel of the forward vehicle of the truck or truck tractor in front of it.''
(b) General Limitations.--(1) Except as provided in this section, a State may not prescribe or enforce a regulation of commerce that--
...(D) "imposes a vehicle length limitation of not less than or more than 97 feet on a driveaway saddlemount with fullmount vehicle transporter combinations;''
The Federal Highway Administration is working to update its regulations in 23 CFR 658 to reflect the changes made by SAFETEA-LU. However, the provisions of SAFETEA-LU are in effect now, as outlined by this letter from the Federal Highway Administration dated September 12, 2005:: saddlemount-fhwa.
This change in federal law applies to the National Network (NN) only. To determine which routes are NN, click here for the Truck Route List in Excel and look for NN in the column "Type."
Click here for photos of 3-truck and 4-truck saddlemount configurations in PDF format.
Caltrans Legal Truck Size & Weight Work Group
General number (916) 654-5741
E-mail: Truck Size & Weight Unit.
Return to the Caltrans "Office of Truck Services" page.