How to Easily Find Engine Serial Numbers (2024)

Anyone who’s ever serviced a vehicle can confirm: There’s no such thing as too much information. The more you know about a car or truck that enters the service bay, the more efficiently you can diagnose issues and make repairs … or get right to work if it’s just in for routine maintenance. Either way, knowledge is power, especially under the hood.

Whether you’re a mechanic, an enthusiast, or someone who just wants to know more about your vehicle’s equipment, the engine serial number provides a wealth of data. This code tells you all about the engine’s past, present, and future. It plays a key role in parts replacement, validating warranties, and tracking service history, among other important functions.

So, where are these mother lodes of information located, how exactly can they help you, and is there any way to find them without getting your hands dirty? Keep reading for our inside scoop on engine serial numbers.

Why Serial Numbers Matter

An engine serial number is a lot like a fingerprint–it's unique to a specific engine and contains all sorts of useful information, including where the engine was manufactured, when it was assembled, and its identifying features. Here are just a few of the reasons why serial numbers are so important:

Parts compatibility: When it's time to replace parts, referencing the serial number ensures you get the right ones, reducing the likelihood of running into compatibility or fitment issues.

Service history: The serial number offers a glimpse into your engine's past, shedding light on any recalls, prior repairs, and potential problems that could crop up down the road.

Warranty claims: If your engine is still under warranty, the serial number is your ironclad assurance that repairs will be covered, saving owners from expensive bills.

Vehicle identification: During inspections, transactions, registrations, or maintenance checks, the engine serial number becomes the primary means of identifying the vehicle. It guarantees that all documentation is accurate, and helps protect against fraud or theft.

Finding Your Engine's Identity

So, where do we find these critical digits? If only the manufacturers had agreed to put them all in the same spot. But then, that wouldn’t be any fun now would it? In fact, their location varies depending on the type of engine and who built it. Here’s how to find them:

Domestic Engines (Chevrolet, Ford, Dodge/Chrysler): Look for a stamped metal plate near the valve cover or engine block. For Chevrolet, it's usually on the driver's side, while Ford’s is typically found on the passenger’s side of the block, just below the cylinder head. For Dodge/Chrysler, check near the oil filter or bellhousing. Sometimes, there's a sticker under the hood with the engine serial number; it might be near the radiator support or on the strut tower.

Japanese Engines (Toyota, Honda, Nissan): The data plate is typically located near the firewall or strut tower. For Honda, it’s generally stamped into the side of the engine, just below the head gasket. Toyota’s are also stamped onto the block, although exact locations may vary by engine type. You could also look for a label under the hood that might contain the engine serial number, along with other vehicle information.

German Engines (BMW, Mercedes): You should find the plate near the starter motor on the engine block. Several BMWs have their engine serial numbers stamped on the block, under the intake manifold runners. For some German vehicles, the number might also be listed in the owner's manual or service booklet.

Diesel Engines (Big rigs): The plate is usually located near the fuel injection pump or valve cover. However, it’s best to consult the owner’s manual for specifics, as this can vary between Cummins, Detroit Diesel, and Caterpillar engines. Also, check for a label under the hood or in the engine compartment that lists the engine serial number.

Heavy Equipment Engines: Check for either a plate near the starter, the engine block by the flywheel, or under the engine access panel. Again, refer to the manual or manufacturer's website for exact locations. For these engines in particular, serial numbers are often used when updating service records and warranty claims, so they may also be included in maintenance logs or manufacturer databases.

Tech Hacks for Modern Mechanics

While some might enjoy spending quality time in their vehicle’s engine bay searching for a serial number (hey, to each his own), you may actually be able to find it faster electronically. Here are a couple of tech-based hacks that could make your life easier:

OBD-II Scanners: Most modern vehicles are equipped with On-Board Diagnostics II (OBD-II) ports, which means that for newer engines, an OBD-II scanner may be able to fetch the serial number for you.

Manufacturer Websites: Some manufacturers provide online portals where you can enter a model number or vehicle identification number (VIN) and search their database for detailed information like the engine serial number or any service history.

Pro Tip: Snap a Pic for Later

Once you've found that serial number, snap a clear photo of it with your cell phone. A digital image can come in handy if the physical number ever gets worn out, damaged, or removed. And store this photo someplace safe, along with the vehicle’s other important information, so you always have a reliable backup.

Now That You’ve Cracked The Code