02 / MEASUREMENTS
Bring the trailer measurements, not just the cargo drawing.
Kingpin-to-rear-axle distance affects access.
California's length rules distinguish semitrailer length, combination length and kingpin-to-rear-axle distance. STAA access and local restrictions also matter. A 53′ trailer is not enough information on its own; record the rear-axle position and intended route when selecting equipment.
Keep cargo and loaded dimensions separate.
The Caltrans application asks for cargo dimensions, hauling equipment, vehicle measurements and loaded height, width, length and overhang. For overweight applications it also asks for axle spacing and weights. Retain those distinctions so a cargo height is never mistaken for pavement-to-top loaded height.
03 / ROUTE
A legal height does not guarantee clearance.
Check the roads below the load, not just a statewide number.
Caltrans lists a 14′ general height limit but also publishes lower clearances on state routes. The list excludes local roads passing under state highways. Single-trip guidance calls for 3″ clearance below the lowest structure on the permitted route; exact loaded height and the local approach still need checking.
Pilot-car requirements follow the route colors.
Caltrans' single-trip pilot-car maps are organized by district and use five route colors with a dimensional legend. The same load can need different accompaniment on another road. Use the route-specific conditions, and coordinate any required California Highway Patrol escort separately.
04 / FEES
One direction of travel is one trip.
A return movement needs its own assessment.
Caltrans' single-trip product is for one-way movement and is valid for seven consecutive days. If the return vehicle remains extralegal, it needs another permit because the opposite direction can have different clearances and conditions. The application instructions publish a fee for each trip; escort and local-road costs are separate.
Calculator fee reference: Caltrans 2026 Transportation Permits Manual, chapter 1 — single-trip fee
05 / TRAVEL
Keep the accompaniments with the permit.
Urban timing can change the day's schedule.
Caltrans identifies urban curfews for loads over 10′ wide in the Los Angeles, Sacramento, San Diego and San Francisco areas. Holiday, 24/7 travel, pilot-car and bridge conditions are separate accompaniments where applicable. Follow the forms identified on the issued permit and check current route restrictions before departure.
BEFORE DISPATCH
Match the paperwork to the move.
- Record trailer length, kingpin-to-rear-axle distance and actual loaded dimensions.
- Check district route colors, the lowest structure and local pickup/delivery access.
- Plan outbound and return movements separately and retain the required permit accompaniments.
The issued permit controls the authorized vehicle, load, route and travel conditions. Check current closures and the pickup and delivery approaches. A planning estimate does not approve clearance or replace the permit.
SOURCE RECORD
Go straight to the authority.
ODPermit prepared this guide with AI-assisted review of the official sources below on . This is a dated planning reference, not agency approval or an independently certified legal review. Source dates and the roads, product and load covered by each rule matter.
- Caltrans single-trip permit
Non-reducible loads, route-based dimensions, one-way movement and validity
Official page checked September 7, 2026 - Caltrans single-trip application instructions
Items 8–21, 29 and 35–37: cargo/vehicle measurements, fee, roads and accompaniments
Official page checked September 7, 2026 - Caltrans vehicle lengths
Semitrailer length, kingpin-to-rear-axle distance and STAA access
Official page checked September 7, 2026 - Caltrans height and low clearances
14-foot height rule; state-route clearance table and local-road limits
Official page checked September 7, 2026 - Caltrans single-trip pilot-car maps
District maps, five route colors and pilot-car legend
Official page checked September 7, 2026 - Caltrans permit frequently asked questions
Questions 5–7: accompaniments, urban curfews and escort coordination
Official page checked September 7, 2026