12.3 Motor Carrier / Trucking and MCS-90
Key Takeaways
- Trucking risks use the Truckers (CA 00 10) or Motor Carrier (CA 00 12) forms; the Motor Carrier form is the modern choice and supports trailer interchange and MCS-90 filings.
- Trailer interchange covers the insured's legal liability for physical damage to NON-OWNED trailers held under a WRITTEN agreement; owned trailers are covered as autos.
- The MCS-90 guarantees payment to the injured public even for otherwise-excluded losses, and the insurer can seek reimbursement from the insured.
- FMCSA minimum public-liability limits are $750,000 (non-hazardous), $1,000,000 (oil/certain hazmat), and $5,000,000 (hazardous materials/explosives).
- Neither liability, the MCS-90, nor trailer interchange covers hauled freight — that requires Motor Truck Cargo (inland marine).
Why Trucking Needs Its Own Forms
The standard Business Auto form does not address two realities of for-hire trucking: carriers routinely swap trailers with one another, and interstate carriers must satisfy federal financial-responsibility rules. ISO answers with two trucking forms:
- Truckers Coverage Form (CA 00 10) — the original form for for-hire carriers.
- Motor Carrier Coverage Form (CA 00 12) — the modern, broader choice that suits both private and for-hire carriers and incorporates trailer-interchange handling.
Most trucking risks today are written on the Motor Carrier Coverage Form because it accommodates the widest range of operations and supports the federal filings carriers need.
Trucking Forms vs. the Standard BAP
| Feature | Trucking / Motor Carrier Forms | Standard BAP (CA 00 01) |
|---|---|---|
| Target market | For-hire and private carriers | General commercial |
| Trailer interchange | Built-in provisions | Not addressed |
| MCS-90 capability | Yes (federal filings) | Generally no |
| Cargo | Endorsement / separate policy | Separate policy |
The trucking forms also use covered-auto symbols, but they add concepts the BAP lacks — most importantly the handling of non-owned trailers in the insured's possession under interchange agreements.
Trailer Interchange
Carriers exchange trailers under written interchange agreements so a load can move efficiently across regions. Trailer interchange coverage insures the insured's legal liability for physical damage to a non-owned trailer in its possession under such an agreement. Comprehensive, specified-causes-of-loss, or collision bases can apply, each with a deductible.
Key limits:
- It covers non-owned trailers only — the insured's owned trailers are covered as autos under physical damage.
- There must be a written trailer-interchange agreement; an informal swap may not trigger coverage.
- It is liability-based physical damage — the insured pays only when legally responsible for the damage to the borrowed trailer.
Federal Financial Responsibility — the MCS-90
Interstate for-hire carriers must prove financial responsibility under 49 CFR Part 387 (FMCSA). The MCS-90 endorsement attaches to the auto liability policy and acts as a surety-like guarantee: the insurer will pay a judgment to a member of the injured public even if the specific loss would otherwise be excluded or uncovered under the policy — for example, an unscheduled or improperly disclosed vehicle.
The MCS-90 protects the public, not the insured. After paying, the insurer may seek reimbursement from the insured for any amount it would not have owed but for the endorsement.
| Cargo Hauled | FMCSA Minimum Public Liability |
|---|---|
| Non-hazardous property (most freight) | $750,000 |
| Oil / certain hazardous substances | $1,000,000 |
| Hazardous materials / explosives / certain HM | $5,000,000 |
The FMCSA filing that evidences this coverage is the BMC-91 / BMC-91X; a BMC-85 surety bond is the alternative proof. Intrastate carriers follow state minimums, which may differ from the federal tiers.
Motor Truck Cargo — the Coverage Liability Forgets
Neither auto liability, the MCS-90, nor trailer interchange insures the freight a carrier is hauling for others. The auto policy's care, custody, or control exclusion bars coverage for property in the insured's possession, and the MCS-90 protects the public — not cargo.
Motor truck cargo coverage (an inland marine line) insures the carrier's legal liability for loss to the property of others in transit. It is rated by commodity and limit per vehicle/per occurrence, and shippers and brokers commonly require a minimum cargo limit before tendering a load.
Form-selection summary: for-hire interstate carrier needing FMCSA filing → Motor Carrier (CA 00 12) + MCS-90; carriers swapping trailers under written agreements → Motor Carrier with trailer interchange; protection for hauled freight → Motor Truck Cargo (inland marine).
An interstate for-hire carrier hauling general (non-hazardous) freight must file proof of financial responsibility under 49 CFR Part 387. What is the minimum public-liability limit, and what does the MCS-90 endorsement guarantee?
A carrier takes possession of another company's trailer under a written interchange agreement and the trailer is damaged in a covered loss for which the carrier is legally liable. Which coverage responds?
The MCS-90 and Why It Is Not Really Coverage
For-hire interstate truckers must meet federal financial-responsibility minimums (commonly $750,000, rising to $1,000,000 or $5,000,000 for hazardous cargo) under FMCSA rules. Compliance is shown by attaching the MCS-90 endorsement to the auto policy.
Key exam point: the MCS-90 is a surety-like public-protection guarantee, not coverage for the insured. If the policy would not otherwise pay (e.g., the loss falls in a coverage gap, or involved an unscheduled auto), the insurer must still pay the injured public up to the federal minimum — and then the insurer is entitled to reimbursement from the trucker. It protects the public, not the insured, and the insured ultimately owes the money back.
The Trucking/Motor Carrier coverage forms also handle the trailer interchange exposure: when carriers swap trailers under interchange agreements, Trailer Interchange coverage insures the trucker's legal liability for physical damage to a non-owned trailer in its possession under a written agreement. And because the liability forms exclude damage to the cargo itself, the trucker buys separate Motor Truck Cargo coverage to insure the freight it hauls — the coverage liability "forgets."
Primary vs. Hired/Borrowed Liability and the Trucker's Stack
Trucking exposes a layered liability question the exam likes: who pays when a leased owner-operator's tractor, pulling the motor carrier's trailer, causes an accident? The federal leasing regulations and the policy's who-is-an-insured wording generally make the motor carrier responsible to the public while the truck is in its service, with the MCS-90 standing behind any gap up to the federal minimum.
Endorsements such as the Truckers – Insurance for Non-Trucking Use (Bobtail) form address the opposite situation: when the owner-operator drives the tractor without a trailer and not in the carrier's business, the carrier's policy does not respond, so the owner buys bobtail/non-trucking-use coverage.
Worked layering: A hazardous-materials hauler needs the $5,000,000 federal minimum. If its primary BAP carries $1,000,000, it stacks a $4,000,000 commercial umbrella above it, and the MCS-90 is attached to evidence compliance. Remember the MCS-90 figure scales with cargo: $750,000 general freight, $1,000,000 most hazardous, $5,000,000 for the most dangerous materials. Matching the right minimum and the right endorsement (MCS-90 for public protection, bobtail for non-business use, trailer interchange for swapped trailers, motor truck cargo for the freight) is the precise skill these trucking questions test.