Quick Guide: Truck Lengths & Routes

The 3-Step Quick Guide to help you determine which routes your truck may legally travel on.

Step 1 |Step 2 | Step 3 | Step 4 (Optional) | Step 5 (Optional)


Step 1: Determine Your Truck Category

The two categories of truck tractor-semitrailers in California are: (1) the "green" trucks (Interstate "STAA" trucks) and (2) the "black" trucks (California Legal trucks). These two tables show the maximum allowed lengths for the two categories of truck tractor-semitrailers.

Truck Tractor - Semitrailers:

Lengths "Green" STAA Trucks "Black" California Legal Trucks
  CA STAA 53ft Image CA STAA 48ft Image CA Legal Truck Image
Route Colors: blue line Green Line blue line blue line black line
Overall Length: unlimited unlimited 65 feet Max
Semitrailer: 53 feet Max 48 feet Max unlimited
KPRA (kingpin-to-rearmost-axle distance): 40 feet Max
(two-axle semitrailer);
38 feet Max
(single-axle semitrailer)
unlimited 40 feet Max
(two-axle semitrailer);
38 feet Max
(single-axle semitrailer)

Doubles:

Lengths "Green" STAA Trucks "Black" California Legal Trucks
  CA STAA Double Image CA Legal Double Image
Route Colors: blue line blue line black line
    Option A Option B
Overall Length: unlimited 75 feet Max 65 feet Max
Trailers: 28 ft - 6 inch Max
(each trailer)
28 ft - 6 inch Max
(each trailer)
28 ft - 6 inch Max
(one trailer)
unlimited (other trailer)

Step 2: Determine the State Routes You Can Use

The color-coded "California Truck Network Map" for State highways is the official government source for truck route information. There are many private truck route guides, e.g., the Rand McNally Motor Carrier Atlas and various GPS systems. However, the accuracy of those private guides cannot be guaranteed, and must be verified by consulting the official "Caltrans Truck Network Map." The table below shows which color routes on the map your truck may legally travel on.

Route Colors Route Type Signs "Green" STAA Trucks "Black" California Legal Trucks

Green
Primarily
interstates
None Yes Yes
blue line
Blue
State routes Yes Yes
black line
Black
State routes Usually none No Yes

Yellow
(KPRA Advisory Routes)
State routes No

Yes -- However, we advise you not to travel on an advisory route unless your KPRA is no more than the posted length, which is 30 feet on most routes.


Red
Varies Example:
The restriction may or may not apply to you. Read the restriction on the map to determine whether it applies. See also the Special Route Restrictions.

Signage: These two signs indicate where a "green" STAA truck may travel off the interstates.

Signage Route Type Sign Graphics Purpose
T-Sign
G66-56 (CA)
State Route
Terminal Access
The T-Signs are trailblazer signs showing "Terminal Access" routes where STAA trucks may exit off the interstate and travel onto State and local routes. These T-Signs are also posted on the State and local Terminal Access routes at decision points. If the T-Sign is not posted, a STAA truck may not travel there. If the Terminal Access route deadends, there will be a T-End sign at or near the turnaround location.
S-Sign
G66-55 (CA)
Service Access The S-Signs are Service Access signs showing where STAA trucks may exit the interstate onto a local road, for one mile only, for food, fuel, lodging, or repair.

Step 3: Determine the Local Roads You Can Use

  • Destination: Locate your destination using Google Maps to determine which local roads you will need to travel on.
  • Local Terminal Access & Truck Route Maps: Listing of some local Terminal Access and Truck Route maps and municipal codes. The list is not complete. Our office adds links to local truck maps on this page as we learn of them.
  • Local Truck Routes: Most cities and counties allow only the "black" California Legal trucks, and only on certain "truck routes" which are posted with "truck route" signs.
  • Local Terminal Access Routes: Most cities and counties have not approved any local Terminal Access routes for the "green" STAA trucks. If a local road has been approved as a Terminal Access route for STAA trucks, the State ramp will be approved by Caltrans and a T-sign will be posted at or near the highway exit leading to the local Terminal Access route.
  • Local Contacts: For local truck access in cities or counties that are not listed on the Caltrans local route list linked above, you would need to contact the local government (e.g. the local office for Public Works, Traffic, Engineering, or Permits, etc.).
  • Signs: Look for these signs in the table below to indicate a local Terminal Access route that allows STAA trucks, or a local "truck route" which allows only California Legal trucks.
Signage Route Type Sign Graphics Purpose
T-Sign
G66-56 (CA)
Local Terminal Access The T-Signs are trailblazer signs showing "Terminal Access" routes where STAA trucks may travel off the interstates and State routes and onto local Terminal Access routes, and at decision points along the route. If the T-Sign is not posted, A STAA truck may not travel there. If the Terminal Access route deadends, there will be a T-End sign at or near the turnaround location.
Truck Route Sign
R14-1 (CA)
Truck Route CA Truck Route Image The Truck Route Signs are posted by cities as trailblazer signs to direct the "black" California Legal trucks on approved truck routes through the cities.

Step 4 (Optional): Apply for a New Local Terminal Access Route

Terminal Access Application: If your "green" STAA truck cannot travel to your destination legally, and you would like to access that facility in the future, it may be worth it to apply for a new local Terminal Access route. Most State routes have already been evaluated, and are continually evaluated as improvement projects are completed; but many local roads have not been evaluated for STAA access. To apply to a local government to evaluate a local route to be considered for Terminal Access, view the Terminal Access Application Procedures.


Step 5 (Optional): Confirm Legal Length Limits in The CA Vehicle Code (CVC)

California Legal Truck: The 65-foot maximum length limit for vehicle combinations is codified in CVC Section 35401 which is copied here in part:

  • 35401. (a) "... a combination of vehicles coupled together, ..., may not exceed a total length of 65 feet."

STAA Truck & Routes: The overall length and semitrailer length limits for STAA trucks, and the State and local authority to identify routes, are codified in CVC Section 35401.5(a) which is copied here in part:

  • 35401.5. (a) "A combination of vehicles consisting of a truck tractor and semitrailer, or of a truck tractor, semitrailer, and trailer, is not subject to the limitations of Sections 35400 and 35401, when operating on the" ... (National Network) ... "or when using routes appropriately identified by the Department of Transportation or local authorities as provided in subdivision (c) or (d), if all of the following conditions are met: (1) The length of the semitrailer in exclusive combination with a truck tractor does not exceed 48 feet. A semitrailer not more than 53 feet in length shall satisfy this requirement when configured with two or more rear axles, the rearmost of which is located 40 feet or less from the kingpin or when configured with a single axle which is located 38 feet or less from the kingpin. ..."