Where truck accidents happen in Diamond Bar
The 60 is the freight spine between the ports, downtown Los Angeles and the Inland Empire, and the 57 is the truck route to Orange County. They meet in Diamond Bar, weave together for two miles, and split again, with the Grand Avenue, Diamond Bar Boulevard and Golden Springs ramps in between. The city has almost no warehouses of its own. What it has is every truck in the region passing through at once, and a construction zone on top of it.
The 57/60 Confluence. The San Gabriel Valley Council of Governments, which is building the fix, cites federal research ranking this interchange the number one location in California for freight delays and truck accidents. The 2026 national bottleneck list puts the 60 at the 57 at sixteenth in the country, with trucks averaging 40 miles an hour through it. Caltrans counts up to 34,000 trucks a day on the 60 at the 57 South junction. On February 20, 2025, two semis collided and overturned on the eastbound 60 at the 57 connector shortly after 4 a.m.; both tankers ended up on their sides, concrete spilled across the lanes, one person died at the scene and another was hurt.
Grand Avenue and the construction zone. Phase three of the Confluence project started in July 2023 and runs to July 2028. It is building a new Grand Avenue bridge with reconfigured on- and off-ramps, an eastbound 60 bypass bridge at Grand, and more bypass bridges over Diamond Bar Boulevard and Prospectors Road. That means shifted lanes, closed shoulders, temporary ramps and overnight closures for years. A truck driver following last week’s lane pattern in this week’s configuration is a crash we expect to see, and when a lane closure or a missing sign contributed, the contractor and Caltrans come into the case.
Diamond Bar Boulevard and Golden Springs Drive. Diamond Bar Boulevard has ramps to both freeways and runs the length of the city, past the shopping centers and the high school. Golden Springs parallels the 60 on its south side from Brea Canyon Road to Grand and has had its traffic pattern changed by the project since 2024. Trucks that bail off a stopped 60 to try surface streets end up on both, and a rig making a wide turn at Diamond Bar Boulevard and Golden Springs or Grand and Golden Springs is where the surface-street truck crashes in this city concentrate.
Brea Canyon Road and Lemon Avenue. Brea Canyon Road is the surface route from the 60 south along the 57 to Brea, and it borders the City of Industry warehouse district on Diamond Bar’s west side. In 2018 the state opened new 60 ramps at Lemon Avenue and permanently closed the eastbound on-ramp at Brea Canyon, specifically to move Industry’s truck traffic off Diamond Bar’s streets. Trucks still use Brea Canyon to reach the 57 southbound, and the Lemon Avenue ramps now carry the warehouse rigs, so the crashes moved rather than disappeared.
Pathfinder Road and the 57 south of the split. South of the confluence the 57 drops toward Brea Canyon with exits at Pathfinder and Diamond Bar Boulevard, and Caltrans counts about 121,000 vehicles a day here. The grade and the curves are where a truck that was fine on the flat loses its brakes or its trailer. Pathfinder connects the residential hills to the freeway and to Diamond Bar High School, so trucks getting on and off there meet school traffic twice a day.
Sunset Crossing, Temple and the north end. At the north end, the 57 exits at Sunset Crossing Road and Golden Springs and Temple Avenue before it climbs toward the 10 and the 71 in Pomona. Trucks bound for Cal Poly’s side of Pomona and the 10 use Temple, and the ramps here sit close together in a stretch where the freeway is still carrying the full load of 57 and 60 traffic that has not yet split. Rear-end crashes into the backup from the split are the pattern.
Federal researchers have ranked the 57/60 among the nation’s worst truck bottlenecks for years, and the state calls it the second highest truck accident location in Southern California. That history is not just background. It shows the carrier knew this stretch requires slower speeds and longer following distances, and it puts Caltrans and the construction contractor in the picture when a lane shift or a closure played a part.
The crash that defines this interchange happened on February 20, 2025. Shortly after 4 a.m., two semis, both tankers, collided on the eastbound 60 at the connector to the 57 in Diamond Bar. Both trucks overturned, concrete poured across the lanes, one person was pronounced dead at the scene by county firefighters and another was injured. Three connector lanes stayed closed through the morning commute for cleanup. In September 2026 the CHP logged two more big rig collisions at the Diamond Bar Boulevard ramps on the 60, one of them with an ambulance called to the scene. This is the stretch where a routine backup turns into a fatal crash.
Why a truck case is not a big car accident case
The defendant is a company with an insurer and a lawyer, the rules it broke are federal, and the proof of what happened is stored on its truck. Each of those changes how the case has to be built.
Federal safety rules set the standard of care
Nearly every rig coming through the confluence is hauling freight that crossed a state line, which puts the carrier under the Federal Motor Carrier Safety Regulations. The driver gets eleven hours behind the wheel inside a fourteen-hour day with a thirty-minute break under Part 395, must be qualified under Part 391 and tested under Part 382, and the truck must be inspected and maintained under Part 396. A violation that caused the crash at Grand Avenue is negligence per se in California, and the carrier has to explain the violation rather than you having to prove what a careful driver would have done.
The coverage is measured in millions
A car on Diamond Bar Boulevard can be insured for $30,000 per person, which does not cover the first day at Pomona Valley’s trauma unit. A truck over 10,001 pounds hauling general freight in interstate commerce must carry at least $750,000 under 49 CFR 387.9. A tanker carrying certain hazardous materials, like the ones that overturned here in 2025, must carry $5 million. Most carriers add excess policies above that. The money is there to pay for a serious injury, and the insurer knows it.
More than one company is on the hook
The driver works for a carrier that may lease its tractor from one company and pull a trailer owned by another. A broker matched the load, a distribution center in Industry or Ontario loaded it, and an outside shop signed off on the brakes. In a construction-zone crash on the 57/60, Caltrans and the contractor that set the lane closure can share fault too. Each of them has its own policy, and the first job is finding all of them before the carrier makes the driver the only defendant.
The evidence is on a clock
Federal rules only require a carrier to keep electronic driver logs for six months. The engine’s crash data can be overwritten the next time the truck goes to work, and dash-cam video is deleted on a rolling schedule. On the 57/60 there is one more clock: the construction zone changes, and the lane pattern that existed the night of the crash is gone in weeks. We send a written preservation demand to the carrier, the broker, the insurer and, when it applies, the contractor within days, and we photograph the zone before it moves.
The evidence we lock down in the first 72 hours
The trucking company’s insurer usually has an adjuster and an accident reconstructionist on a serious crash the same day. This is what we go after to level that field.
- Electronic logging device data. The driver’s hours for the trip and the seven days before it. A pre-dawn crash at the 57 connector starts with the question of how long the driver had been awake, and the log answers it or was edited.
- Engine control module download. Speed, throttle, brake application and following distance in the seconds before impact. In the backup at Grand Avenue, it settles whether the truck could have stopped.
- Dash-cam and cab-facing video. Most fleets run cameras both ways. Video of a driver on a phone coming into a shifted lane pattern changes a case in a single frame.
- Driver qualification file. License history, medical card, prior crashes and citations, training records, and the hazardous materials endorsement a tanker driver is required to hold.
- Post-crash drug and alcohol tests. Federal rules require testing after a crash with a death, an injury treated away from the scene, or a tow. We confirm the test was done on time and get the result.
- Construction zone and traffic control records. The contractor’s lane closure plan, the sign and cone layout on the night of the crash, the Caltrans permit and the daily logs. When the zone contributed, these records are the case.
Who can be held responsible for a Diamond Bar truck crash
- The truck driver
- For speeding, tailgating, an unsafe lane change through the weave, missing a lane shift, running a signal on Grand or Diamond Bar Boulevard, distraction, fatigue or impairment. California also limits any vehicle with three or more axles or a trailer to 55 miles an hour and the right-hand lanes under Vehicle Code 22406.
- The motor carrier
- The company whose USDOT number is on the door answers for its driver’s negligence and for its own: hiring a driver with a bad record, dispatching him past the hours limit, or skipping maintenance to keep the truck on the road. We check the carrier’s federal safety record before the first call with its adjuster.
- The freight broker and the shipper
- A broker that hands loads to carriers with poor safety scores can be liable for negligent selection. A shipper that loaded and sealed the trailer, or filled a tanker past its rated weight, can be liable when the load caused the crash.
- Tractor and trailer owners, lessors and maintenance shops
- The tractor and the trailer often have different owners, and a leasing company or a contract shop that signed off on worn brakes or a bad tire becomes a defendant with its own insurance.
- Manufacturers
- Brake failures, tire blowouts, tanker rollover stability and trailers without proper rear underride guards support product liability claims against the companies that built or sold them.
- Caltrans, Metro, the City of Diamond Bar or the construction contractor
- When a lane closure, a missing sign, a temporary ramp, a bad signal or the work zone on the 57/60 contributed to the crash, a government claim must be filed within six months under Government Code 911.2, and the private contractor is sued directly. We calendar that deadline the day we open the file.
After a truck crash in Diamond Bar: who to call and where to go
What a Diamond Bar truck accident claim can recover
The companies responsible for the truck owe the full cost of what the crash did to you, not the number their adjuster offers before you have seen a doctor. In a truck case that usually includes:
- Emergency and hospital care the ambulance, the trauma unit at Pomona Valley, surgery, imaging and the months of physical therapy that follow a high-energy crash.
- Future medical care a life-care plan when a brain injury, spinal cord injury, burns or an amputation will need treatment for years.
- Lost wages and lost earning capacity the paychecks you missed and the job you cannot go back to.
- Pain, suffering and the loss of your normal life which California does not cap in a trucking case.
- Your car and your property the vehicle, the rental, and what was inside it.
- Wrongful death damages for a spouse, children or parents under Code of Civil Procedure section 377.60, including funeral costs and the loss of the person’s support, guidance and companionship.
Under California’s pure comparative negligence rule, a share of fault reduces the recovery by that share; it does not bar the claim. Immigration status has no bearing on any of it.
Abogado de accidentes de camión en Diamond Bar
Si un tráiler, un camión cisterna o una camioneta de reparto lo lesionó en Diamond Bar, en el cruce de la 57 y la 60, en Grand Avenue, Diamond Bar Boulevard, Golden Springs o Brea Canyon Road, la compañía de transporte y su aseguradora ya están trabajando para pagarle lo menos posible. Ese cruce es de los peores del país para los camiones, y con la construcción los carriles cambian cada semana. Usted tiene derecho a que cubran la sala de emergencias, el tratamiento, los salarios perdidos, el carro y el daño a su vida. El abogado Francisco Morales atiende su caso personalmente en español, sin intermediarios. La consulta es gratis y no paga honorarios si no recuperamos dinero para usted. Su estatus migratorio no cambia sus derechos. No dé una declaración grabada a la aseguradora del camión. Llámenos primero.
A local attorney who handles the case himself
Search for a Diamond Bar truck accident attorney and most of what you find is downtown Los Angeles and Orange County offices running one template for every city on the 57. Morales Law Firm is on Bonita Avenue in San Dimas, fifteen minutes north on the 57. Francisco Morales grew up in West Covina, graduated from UCLA and Loyola Law School, and worked as a certified automotive service consultant before he became a lawyer, which is useful when the argument is about brakes, following distance and what a truck’s data actually shows. He is fully bilingual in English and Spanish, he answers his own phone, and he does not hand truck cases to a case manager. More about Francisco.
We handle truck and big rig crashes throughout the San Gabriel Valley and the Inland Empire, along with car accidents in Diamond Bar, 57/60 interchange collisions, motorcycle crashes, pedestrian injuries, wrongful death and uninsured motorist claims, and we come to you in Diamond Bar when that is easier.
Diamond Bar truck accident questions
Who investigates a truck accident in Diamond Bar?
If it happened on the 57, the 60 or the connectors between them, the California Highway Patrol handles it out of the Baldwin Park Area office at 14039 Francisquito Ave., which covers the 57/60 interchange. Diamond Bar does not have its own police department; the Los Angeles County Sheriff’s Walnut/Diamond Bar Station at 21695 E. Valley Blvd. in Walnut handles crashes on Grand, Diamond Bar Boulevard, Golden Springs, Brea Canyon Road and the other city streets. We get the report either way, and on a serious freeway crash we find out whether the CHP’s Multidisciplinary Accident Investigation Team responded.
How much does a Diamond Bar truck accident lawyer cost?
Nothing up front. We work on a contingency fee, a percentage of the recovery that is paid only when the case resolves. If there is no recovery there is no attorney’s fee. We advance the cost of accident reconstruction, engineers, medical witnesses, records and depositions while the case is open, and the first consultation is free. The carrier’s insurer handles truck claims every day and you are handling one once, so make the call before you give a recorded statement.
Where would a Diamond Bar truck accident lawsuit be filed?
Diamond Bar is in the East District of the Los Angeles Superior Court, so a serious injury case is filed as an unlimited civil case at the Pomona Courthouse South, 400 Civic Center Plaza. Since the court closed its downtown personal injury hub, cases are heard in the district where the crash happened. If Caltrans or Metro is a defendant because of the construction zone, a government claim comes first. If the trucking company is based out of state, it may move the case to federal court in Los Angeles, and we plan for that from the start.
How far is your office from Diamond Bar?
About ten miles, fifteen minutes. Take the 60 or Grand Avenue to the 57 north, exit Bonita Avenue and head east into downtown San Dimas. We are at 151 W. Bonita Ave. with free parking. Francisco also meets Diamond Bar clients at home or at Pomona Valley Hospital when driving is not an option after a crash.
¿Hablan español?
Sí. El abogado Francisco Morales es completamente bilingüe y maneja su caso de accidente de camión en español de principio a fin: la consulta, las negociaciones con la aseguradora del camión, los documentos y el acuerdo final. Usted habla directamente con el abogado, no con un asistente.
How long do I have to file a claim after a truck crash in Diamond Bar?
Two years from the crash to file a lawsuit for injuries or wrongful death under Code of Civil Procedure 335.1. If Caltrans, Metro, the City of Diamond Bar or another public entity contributed to the crash, which is a real question anywhere inside the 57/60 construction zone, a government claim is due within six months under Government Code 911.2. The useful deadline is much shorter than either, because the carrier only has to keep the driver’s logs for six months and the work zone itself changes within weeks.
What makes a truck crash different from a car crash?
The weight, the rules, the money and the evidence. An 80,000-pound rig does damage a car cannot, so the injuries are worse. The company that runs the truck must follow federal hours, drug testing, hiring and maintenance rules, and breaking one is negligence per se. It carries at least $750,000 in coverage and usually far more. And it holds the log, the engine data and the video that show what happened, and sends investigators to the scene the same day. The case is won by getting that evidence early.
The crash happened in the 57/60 construction zone. Does that change my case?
It can add defendants. The Confluence project runs through July 2028 and keeps shifting lanes, ramps and shoulders around Grand Avenue, Diamond Bar Boulevard and Golden Springs. If a lane closure, a missing sign, a temporary ramp or a confusing pattern contributed to the crash, Caltrans and the construction contractor can share fault with the trucking company. The claim against the public agency must be filed within six months, and the traffic control plan and daily logs for that night have to be requested quickly, because the zone will not look the same by the time a lawsuit is filed.
The truck driver says I stopped short or cut him off. What now?
That is the standard defense, and the truck’s own equipment usually answers it. The forward camera, the engine control module and the electronic log show the truck’s speed, braking and following distance in the seconds before impact. If the rig was over the 55 mile-an-hour truck limit through the weave or was tailgating in the Grand Avenue backup, the picture changes. California follows pure comparative negligence, so even if you carry part of the fault, your recovery is reduced by that share rather than eliminated.
Can I get medical treatment if I do not have health insurance?
Yes. Go to Pomona Valley Hospital on Garey Avenue, which is the closest trauma center, or to Chino Valley Medical Center east on the 60, right after the crash. After that we arrange treatment with orthopedists, physical therapists, chiropractors and imaging centers in the Pomona and Diamond Bar area who treat on a lien and are paid from the settlement. Immigration status does not affect your right to treatment or to a recovery.