Index
Why the feed is the most critical factor of a VLA campaign
What data the vehicle feed must include
Accepted formats and how to upload it to Google Merchant Center
Update frequency: when is it enough and when is it not
How to automate synchronisation from your DMS
The most common feed errors in Merchant Center
How to verify that the feed is working correctly
Frequently asked questions
Why the feed is the most critical factor of a VLA campaign
Unlike traditional search campaigns where the advertiser controls the keywords, in VLAs it is Google that decides which vehicle to show in each search based on the feed data. The quality and update-frequency of the feed directly determine the quality of the ads.
A well-constructed feed updated in real time has three positive effects. Firstly, Google can match each vehicle with the most relevant searches, generating clicks from buyers with real purchase intent. Secondly, when the user reaches the vehicle page, the information matches exactly what they saw in the ad (price, photos, availability), which reduces bounce rates and increases conversion. Thirdly, the Performance Max algorithm can learn faster about which vehicles generate conversions and optimise budget distribution.
An outdated feed has the opposite effect: ads for cars already sold that generate clicks without conversion, incorrect prices that build distrust, and an algorithm that cannot optimise because conversion signals are not consistent with real inventory.
To fully understand how VLAs work before diving deep into feed synchronisation, you can review the complete Google Vehicle Ads guide for car dealerships.
What data the vehicle feed must include
Google defines a technical specification for the vehicle feed with mandatory and optional attributes. The mandatory ones are the minimum required for a vehicle to appear in ads; the optional ones improve the relevance and quality of the ad.
Mandatory attributes:
id: Unique identifier of the vehicle in the dealership's system (usually the VIN or an internal ID)title: Title of the ad. Recommended format: "Make Model Version Year" (e.g., "Volkswagen Golf TDI 2019")description: Description of the vehicle. It must include main features and conditionlink: URL of the vehicle detail page on the dealership's websiteimage_link: URL of the main image of the vehicle (minimum 400×300 px, recommended 800×600 or higher)price: Price of the vehicle with currency (e.g., "12500 EUR")availability: Availability of the vehicle ("in stock" if available, "out of stock" if sold)condition: Physical condition of the vehicle ("new" for new, "used" for used)brand: Brand/Make of the vehiclemodel: Model of the vehicleyear: Year of manufacturemileage: Mileage (format: "85000 km")vin: Vehicle Identification Number
Optional attributes that improve performance:
fuel_type: Fuel type (petrol, diesel, hybrid, electric)transmission: Transmission type (manual, automatic)body_style: Body type (saloon, SUV, estate, etc.)color: Exterior colouradditional_image_link: URLs of additional images (up to 10 images)vehicle_registration_date: First registration datenumber_of_doors: Number of doorsengine_displacement: Engine size / displacement
The more optional attributes completed, the greater Google's ability to match the vehicle with specific, detailed searches ("blue manual Golf TDI 2019"). For the complete, updated technical specification, you can download the free Google VLA guide for dealerships which includes a ready-to-use feed template.
Accepted formats and how to upload it to Google Merchant Center
Google Merchant Center accepts vehicle feeds in three main formats.
XML. The most common format for dynamic feeds. It allows structuring information hierarchically and is the format generated by most dealership management systems (DMS) with native integration with Google Merchant Center.
CSV (spreadsheet). Simpler to generate manually, but less efficient for large stocks or high turnover. Each vehicle occupies a row and each attribute a column.
Google Sheets. Google Merchant Center allows linking a Google Sheets spreadsheet directly as the feed source. Useful for dealerships managing stock in spreadsheets who want to avoid the manual export and import process.
How to upload the feed to Merchant Center:
In Google Merchant Center, go to "Products" → "Feeds" → "+" and select "Vehicles" as the feed type. You can upload a file (for manual updates) or provide a URL from which Google downloads the feed periodically (recommended for dynamic stocks). If you use a URL, Google can be configured to download the feed as often as you need: hourly, every 4 hours, or every 24 hours.
Update frequency: when is it enough and when is it not
The update frequency of the feed should be proportional to the dealership's stock turnover.
For dealerships with high turnover (10+ cars a month): a daily update is the minimum. If you sell three or four cars a week, a daily update can leave you with active ads for cars sold the day before for several hours. In this case, hourly or real-time updating is the most efficient option.
For dealerships with medium turnover (5-10 cars a month): a daily update is sufficient. Setting Google Merchant Center to download the feed once a day, preferably overnight when there is less activity, ensures that the day's ads are up to date.
For dealerships with stable stock (fewer than 5 cars a month): updating every two or three days may be sufficient. But even in these cases, when a car is sold, you must ensure the feed is updated that same day to avoid wasted clicks.
The rule of thumb is that no sold car should remain active in the feed for more than 24 hours.
How to automate synchronisation from your DMS
The most efficient way to keep the feed updated is through direct integration between the dealership's DMS and Google Merchant Center. With this integration, the feed is updated automatically every time a change occurs in stock: adding a new vehicle, price change, or sale. The dealership does not have to manage the feed manually.
The advantages of automatic synchronisation:
When a car is marked as sold in the DMS, its status in the feed automatically changes to "out of stock" and the ad stops showing. When a new car enters stock, it appears in the feed and therefore in ads within hours. Price changes propagate to the feed without manual intervention, ensuring that the ad price always matches the actual price.
Which systems allow this integration:
Specialised automotive management platforms (DMS) with native integration with Google Merchant Center generate the feed automatically and keep it updated in real-time. Dealcar has this integration built into the platform: stock is automatically synchronised with Merchant Center with no additional setup needed from the dealership.
For dealerships that do not use a DMS with native integration, the alternative is to generate the feed from their current management system (in CSV or XML) and configure the scheduled fetch of that file in Merchant Center. It is more manual but viable if stock turnover is not very high.
VLA synchronisation is part of a broader stock distribution strategy. To see how to integrate it with portal multi-posting, check out the article on car multi-posting for dealerships.
The most common feed errors in Merchant Center
Google Merchant Center validates the feed when it is uploaded and displays errors that prevent certain vehicles from being approved for ads. These are the most common.
Images that do not meet minimum requirements. Insufficient resolution (minimum 400×300 px), branded watermark, manufacturer stock photo instead of the actual vehicle, or broken image URL. Images are the first visual element of the ad, and Google validates them under strict criteria.
To improve the quality of your vehicle photos for both the feed and listing portals, you can review our guide on how to make your cars stand out on portals.
Price does not match the website. Google crawls the dealership's website and verifies that the price in the feed matches the visible price on the vehicle detail page. If there is a discrepancy, the ad is rejected. Ensure that the price in the feed is exactly the same as the one on that vehicle's page on your live website.
Broken or inaccessible vehicle URL. If the vehicle's URL in the feed returns a 404 error or does not load correctly, the ad cannot be published. This happens when a vehicle's page is removed from the web without updating the feed.
Invalid or duplicate VIN. The chassis/VIN number must be unique for each vehicle and in the correct format (17 alphanumeric characters). If two vehicles have the same VIN in the feed (duplicate error), both may be rejected.
Incorrect availability. If a vehicle is listed as "in stock" in the feed but the website page indicates it is no longer available (or vice versa), Google may reject the ad due to inconsistency.
How to verify that the feed is working correctly
Once the feed is configured, there are three checks that must be carried out on a regular basis.
In Google Merchant Center: check the "Products" → "Product status" section weekly. This shows how many vehicles are approved, how many are under review, and how many are rejected, along with the reason for rejection for those not approved. The goal is to have the highest possible percentage of approved vehicles.
Comparison between real stock and feed. At least fortnightly, verify that the number of vehicles in the feed matches the number of available cars in the actual stock. If there are discrepancies (cars in the feed that no longer exist in stock, or cars in stock that are not in the feed), there is a synchronisation issue.
Price verification. Periodically review that feed prices match those on the website pages, especially after bulk price updates or price drops on old stock.
To understand how to measure whether feed improvements are boosting campaign performance, you can check out the article on how to measure the performance of your Google Vehicle Ads campaigns.
More than 750 dealerships already use Dealcar to manage their daily operations
Dealcar automatically generates and maintains the Google Merchant Center feed using the stock catalogued on the platform. When a car enters stock, it appears in the feed. When it is sold, it disappears. Prices and images sync in real-time. Without any extra manual work, the feed is always updated and the VLA ads reflect the real state of your inventory.
If you want to see how it works, you can schedule a free demo at dealcar.io.
Frequently asked questions
How many vehicles do I need in the feed for the campaign to work well?
There is no official minimum, but the more vehicles the feed has, the greater the variety of search queries the campaign can cover. With fewer than 10 vehicles, coverage is very limited. From 20-30 cars onwards, the system begins to have enough variety to optimise effectively.
Can I have very low-priced vehicles in the feed?
Yes, but the system may not display them as frequently as higher-priced ones because the CPC Google can obtain from a €3,000 car is lower than that of a €15,000 one. There is no explicit minimum price, but in practice, very low-priced vehicles have lower visibility in VLAs.
Is the feed the same as the Google Shopping catalogue?
They are similar in concept (both are product feeds for Google Merchant Center) but they have different attribute specifications. The vehicle feed has industry-specific attributes (VIN, mileage, year) that do not exist in the general Shopping catalogue.
Can I use the same feed for VLA and Google Shopping?
No. The vehicle feed and the standard Google Shopping product feed are different feed types in Merchant Center. You must create a specific "Vehicles" type feed for VLAs.
Index
Why the feed is the most critical factor of a VLA campaign
What data the vehicle feed must include
Accepted formats and how to upload it to Google Merchant Center
Update frequency: when is it enough and when is it not
How to automate synchronisation from your DMS
The most common feed errors in Merchant Center
How to verify that the feed is working correctly
Frequently asked questions
Why the feed is the most critical factor of a VLA campaign
Unlike traditional search campaigns where the advertiser controls the keywords, in VLAs it is Google that decides which vehicle to show in each search based on the feed data. The quality and update-frequency of the feed directly determine the quality of the ads.
A well-constructed feed updated in real time has three positive effects. Firstly, Google can match each vehicle with the most relevant searches, generating clicks from buyers with real purchase intent. Secondly, when the user reaches the vehicle page, the information matches exactly what they saw in the ad (price, photos, availability), which reduces bounce rates and increases conversion. Thirdly, the Performance Max algorithm can learn faster about which vehicles generate conversions and optimise budget distribution.
An outdated feed has the opposite effect: ads for cars already sold that generate clicks without conversion, incorrect prices that build distrust, and an algorithm that cannot optimise because conversion signals are not consistent with real inventory.
To fully understand how VLAs work before diving deep into feed synchronisation, you can review the complete Google Vehicle Ads guide for car dealerships.
What data the vehicle feed must include
Google defines a technical specification for the vehicle feed with mandatory and optional attributes. The mandatory ones are the minimum required for a vehicle to appear in ads; the optional ones improve the relevance and quality of the ad.
Mandatory attributes:
id: Unique identifier of the vehicle in the dealership's system (usually the VIN or an internal ID)title: Title of the ad. Recommended format: "Make Model Version Year" (e.g., "Volkswagen Golf TDI 2019")description: Description of the vehicle. It must include main features and conditionlink: URL of the vehicle detail page on the dealership's websiteimage_link: URL of the main image of the vehicle (minimum 400×300 px, recommended 800×600 or higher)price: Price of the vehicle with currency (e.g., "12500 EUR")availability: Availability of the vehicle ("in stock" if available, "out of stock" if sold)condition: Physical condition of the vehicle ("new" for new, "used" for used)brand: Brand/Make of the vehiclemodel: Model of the vehicleyear: Year of manufacturemileage: Mileage (format: "85000 km")vin: Vehicle Identification Number
Optional attributes that improve performance:
fuel_type: Fuel type (petrol, diesel, hybrid, electric)transmission: Transmission type (manual, automatic)body_style: Body type (saloon, SUV, estate, etc.)color: Exterior colouradditional_image_link: URLs of additional images (up to 10 images)vehicle_registration_date: First registration datenumber_of_doors: Number of doorsengine_displacement: Engine size / displacement
The more optional attributes completed, the greater Google's ability to match the vehicle with specific, detailed searches ("blue manual Golf TDI 2019"). For the complete, updated technical specification, you can download the free Google VLA guide for dealerships which includes a ready-to-use feed template.
Accepted formats and how to upload it to Google Merchant Center
Google Merchant Center accepts vehicle feeds in three main formats.
XML. The most common format for dynamic feeds. It allows structuring information hierarchically and is the format generated by most dealership management systems (DMS) with native integration with Google Merchant Center.
CSV (spreadsheet). Simpler to generate manually, but less efficient for large stocks or high turnover. Each vehicle occupies a row and each attribute a column.
Google Sheets. Google Merchant Center allows linking a Google Sheets spreadsheet directly as the feed source. Useful for dealerships managing stock in spreadsheets who want to avoid the manual export and import process.
How to upload the feed to Merchant Center:
In Google Merchant Center, go to "Products" → "Feeds" → "+" and select "Vehicles" as the feed type. You can upload a file (for manual updates) or provide a URL from which Google downloads the feed periodically (recommended for dynamic stocks). If you use a URL, Google can be configured to download the feed as often as you need: hourly, every 4 hours, or every 24 hours.
Update frequency: when is it enough and when is it not
The update frequency of the feed should be proportional to the dealership's stock turnover.
For dealerships with high turnover (10+ cars a month): a daily update is the minimum. If you sell three or four cars a week, a daily update can leave you with active ads for cars sold the day before for several hours. In this case, hourly or real-time updating is the most efficient option.
For dealerships with medium turnover (5-10 cars a month): a daily update is sufficient. Setting Google Merchant Center to download the feed once a day, preferably overnight when there is less activity, ensures that the day's ads are up to date.
For dealerships with stable stock (fewer than 5 cars a month): updating every two or three days may be sufficient. But even in these cases, when a car is sold, you must ensure the feed is updated that same day to avoid wasted clicks.
The rule of thumb is that no sold car should remain active in the feed for more than 24 hours.
How to automate synchronisation from your DMS
The most efficient way to keep the feed updated is through direct integration between the dealership's DMS and Google Merchant Center. With this integration, the feed is updated automatically every time a change occurs in stock: adding a new vehicle, price change, or sale. The dealership does not have to manage the feed manually.
The advantages of automatic synchronisation:
When a car is marked as sold in the DMS, its status in the feed automatically changes to "out of stock" and the ad stops showing. When a new car enters stock, it appears in the feed and therefore in ads within hours. Price changes propagate to the feed without manual intervention, ensuring that the ad price always matches the actual price.
Which systems allow this integration:
Specialised automotive management platforms (DMS) with native integration with Google Merchant Center generate the feed automatically and keep it updated in real-time. Dealcar has this integration built into the platform: stock is automatically synchronised with Merchant Center with no additional setup needed from the dealership.
For dealerships that do not use a DMS with native integration, the alternative is to generate the feed from their current management system (in CSV or XML) and configure the scheduled fetch of that file in Merchant Center. It is more manual but viable if stock turnover is not very high.
VLA synchronisation is part of a broader stock distribution strategy. To see how to integrate it with portal multi-posting, check out the article on car multi-posting for dealerships.
The most common feed errors in Merchant Center
Google Merchant Center validates the feed when it is uploaded and displays errors that prevent certain vehicles from being approved for ads. These are the most common.
Images that do not meet minimum requirements. Insufficient resolution (minimum 400×300 px), branded watermark, manufacturer stock photo instead of the actual vehicle, or broken image URL. Images are the first visual element of the ad, and Google validates them under strict criteria.
To improve the quality of your vehicle photos for both the feed and listing portals, you can review our guide on how to make your cars stand out on portals.
Price does not match the website. Google crawls the dealership's website and verifies that the price in the feed matches the visible price on the vehicle detail page. If there is a discrepancy, the ad is rejected. Ensure that the price in the feed is exactly the same as the one on that vehicle's page on your live website.
Broken or inaccessible vehicle URL. If the vehicle's URL in the feed returns a 404 error or does not load correctly, the ad cannot be published. This happens when a vehicle's page is removed from the web without updating the feed.
Invalid or duplicate VIN. The chassis/VIN number must be unique for each vehicle and in the correct format (17 alphanumeric characters). If two vehicles have the same VIN in the feed (duplicate error), both may be rejected.
Incorrect availability. If a vehicle is listed as "in stock" in the feed but the website page indicates it is no longer available (or vice versa), Google may reject the ad due to inconsistency.
How to verify that the feed is working correctly
Once the feed is configured, there are three checks that must be carried out on a regular basis.
In Google Merchant Center: check the "Products" → "Product status" section weekly. This shows how many vehicles are approved, how many are under review, and how many are rejected, along with the reason for rejection for those not approved. The goal is to have the highest possible percentage of approved vehicles.
Comparison between real stock and feed. At least fortnightly, verify that the number of vehicles in the feed matches the number of available cars in the actual stock. If there are discrepancies (cars in the feed that no longer exist in stock, or cars in stock that are not in the feed), there is a synchronisation issue.
Price verification. Periodically review that feed prices match those on the website pages, especially after bulk price updates or price drops on old stock.
To understand how to measure whether feed improvements are boosting campaign performance, you can check out the article on how to measure the performance of your Google Vehicle Ads campaigns.
More than 750 dealerships already use Dealcar to manage their daily operations
Dealcar automatically generates and maintains the Google Merchant Center feed using the stock catalogued on the platform. When a car enters stock, it appears in the feed. When it is sold, it disappears. Prices and images sync in real-time. Without any extra manual work, the feed is always updated and the VLA ads reflect the real state of your inventory.
If you want to see how it works, you can schedule a free demo at dealcar.io.
Frequently asked questions
How many vehicles do I need in the feed for the campaign to work well?
There is no official minimum, but the more vehicles the feed has, the greater the variety of search queries the campaign can cover. With fewer than 10 vehicles, coverage is very limited. From 20-30 cars onwards, the system begins to have enough variety to optimise effectively.
Can I have very low-priced vehicles in the feed?
Yes, but the system may not display them as frequently as higher-priced ones because the CPC Google can obtain from a €3,000 car is lower than that of a €15,000 one. There is no explicit minimum price, but in practice, very low-priced vehicles have lower visibility in VLAs.
Is the feed the same as the Google Shopping catalogue?
They are similar in concept (both are product feeds for Google Merchant Center) but they have different attribute specifications. The vehicle feed has industry-specific attributes (VIN, mileage, year) that do not exist in the general Shopping catalogue.
Can I use the same feed for VLA and Google Shopping?
No. The vehicle feed and the standard Google Shopping product feed are different feed types in Merchant Center. You must create a specific "Vehicles" type feed for VLAs.
