Chassis Number Check: when chassis number or VIN can be used for history reports
The terms VIN, chassis or frame number are often interchangeable because all of them can be found on a vehicle's frame, identify a unique vehicle and be a key to its history records, a critically important data for those who buy a used vehicle. Often, they are the same as the engine number. However, they are not always identical. The article below is about VIN vs chassis number, while you can read about VIN vs frame number here.
Is chassis number same as VIN?
Not always. On cars, it is so because a modern car does not have a separate frame or chassis. It has a unibody that functions both as the frame and vehicle body at the same time and the VIN plate is attached to a unibody part or is etched on it. The terms chassis or frame number are generally used for other vehicle types, like trucks, motorhomes, that distinguish the frame and the body. Frame number is also used for motorcyles. Sometimes, it may be important to distinguish between the numbers.
What is the difference between the VIN and the chassis number?
In some cases the chassis number may be found on the vehicle's papers and it won't be the same as VIN.
Historically, chassis numbers have been used to identify vehicles before 1989. The were stamped on chassis or frame, the bearing construction of the vehicle. Unlike the VIN for vehicles manufactured after 1981, chassis numbers are not standartized, their length and principles of encoding may vary.
A custom vehicle, like custom trailer, may be assigned a custom VIN number at a local DMV, while chassis number etched on the frame is different and and cannot be changed. Sometimes a vehicle is assigned a custom VIN when the original frame or chassis number is lost, erased or defaced.
On certain vehicles, like RVs, the body and chassis may come from different manufactureres, so the VIN you see on the registrarion papers and the chassis number will be different.
Which number should I use for vehicle history check?
With cars, it makes no difference, as you can infer.
With motorhomes its a wise idea to check both the numbers because chassis may be the actual motor vehicle the history of which is most valuable.
A frequent instance when the VIN number the vehicle is registered with at the DMV does not provide a vehicle history, and the chassis number does, are Forest River motorhomes. They are based on Mercedes chassis, which is the actual motorvehicle in the RV that drives, receives servicing, etc. The chassis have their own number and a solid vehicle history attached to it, including service records. This number is a standard VIN in its essence and is the acutal VIN of the motorvehicle. Howerver, the DMV, the title and other papers may feature another VIN etched on a part of the 'home' which won't have any valuable history as opposed to chassis number. Used motorhome buyers should take this into consideration in order not to miss any critical history records. Some VIN report companies may check both these numbers for your without extra charges or even ask you to provide chassis number if vookup for the VIN returns nothing or no valuable history data. A real example from a VIN history company: an RV based on a 2018 Mercedes-Benz Sprinter chassis with the number WDAPF4CC2JP609032, which has history records. The motorhome itself is registered with 5ZTBGAN0GKR002052 and the VIN does not have any history.
The same may be applicable for heavy duty trucks.