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Questions and Answers About Vehicle Size and Weight

23 CFR 658.23 LCV freeze; cargo carrying unit freeze (ISTEA freeze)

23 CFR 658.23 LCV freeze; cargo carrying unit freeze (ISTEA freeze)

What does LCV mean?

It stands for "longer combination vehicle."
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What is the ISTEA freeze?

ISTEA is an acronym for Intermodal Surface Transportation Efficiency Act of 1991. It imposed two separate freezes: (1) on the maximum weight of longer combination vehicles, which consist of any combination of a truck tractor and two or more trailers or semitrailers which operate on the Interstate System at a gross weight over 80,000 pounds; and (2) on the overall length of the cargo carrying units of combination vehicles with two or more such units where one or both exceed 28.5 feet in length on the National Network. The maximum weight of longer combination vehicles and the maximum length of the cargo carrying units of combination vehicles is the weight or length in actual and legal operation in a State on June 1, 1991, as documented in Appendix C to 23 CFR 658. Also frozen were the routes and conditions in effect on June 1, 1991, for vehicle combinations subject to the freeze, as shown in Appendix C to 23 CFR 658.
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Did the freeze on conditions include height limits and the amount of insurance coverage?

No. These are not related closely enough to the length and weight limitation goals of the ISTEA to be covered by the freeze.
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Since the ISTEA froze the length of the cargo-carrying units for combinations with two or more such units, does it also prevent the Secretary from authorizing longer lengths for specialized equipment?

No. While States may not authorize longer lengths for specialized equipment (e.g., automobile and boat transporters) the Secretary may take whatever action is necessary to accommodate the use of specialized equipment on the NN and reasonable access routes.
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If, in the future, the Secretary authorized longer lengths for specialized equipment, would States have to allow them to use existing reasonable access routes?

No. Under present regulations, States would have the opportunity to alter access routes if they determined that existing routes would not be safe for longer specialized vehicle combinations.
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Are longer combination vehicles subject to standard or grandfathered Interstate System weight limits?

Neither. They are subject only to the maximum weight limits documented in Appendix C to 23 CFR 658 as being in effect on June 1, 1991.
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Are longer combination vehicle maximum weights also minimums?

No. States may reduce them (but not below Interstate minimums) and raise them to the longer combination vehicles maximums at a later date if they wish.
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How is the length of the cargo carrying units measured?

The length is measured from the foremost load carrying structure of the first unit to the rearmost load carrying structure of the last unit, including the hitch or hitches between the units, but excluding the upper coupler on a beverage semitrailer.
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What combination vehicles are not covered by the ISTEA freeze on length?

(1) Twin trailer combinations where neither trailing unit exceeds 28.5 feet in length, (2) automobile and boat transporters where neither trailing unit exceeds 65 feet in overall length (75 feet, if stinger steered), (3) saddlemount combinations not over 75 feet in overall length, (4) truck tractors equipped with a dromedary box, deck, or plate, (5) truck trailer and truck semitrailer combinations not over 65 feet in overall length, and (6) maxi-cube vehicles.
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Is the length of tow trucks with vehicles in tow subject to the ISTEA freeze on length?

No. They are excluded from the freeze on the length of the cargo carrying units. States are free to regulate their length.
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What is the maximum length of automobile transporter combinations that States may allow to operate?

Automobile transporter combinations over 65/75 feet may operate on NN and access routes only as shown in Appendix C to 23 CFR 658.
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Are articulated buses subject to the ISTEA length freeze?

No, because they are not readily separable into two units and, in addition, the freeze applies to combinations with two or more cargo carrying units and passengers are neither property nor cargo.
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