Table of Contents
Why the feed is the most critical factor in 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 in a VLA campaign
Unlike traditional search campaigns where the advertiser controls the keywords, in VLAs it is Google that decides which vehicle to display in each search based on the feed data. The quality and freshness of the feed directly determine the quality of the ads.
A well-structured 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 intent. Secondly, when the user reaches the vehicle's detail page, the information matches exactly what they saw in the ad (price, photos, availability), which reduces the bounce rate and increases conversion. Thirdly, the Performance Max algorithm can learn faster which vehicles generate conversions and optimize budget distribution.
An outdated feed has the opposite effect: ads for cars that have already been sold generating clicks without conversion, incorrect prices that build distrust, and an algorithm that cannot optimize because conversion signals are not consistent with the actual inventory.
To understand the full inner workings of VLAs before diving into feed synchronisation, you can review the complete Google Vehicle Ads guide for dealerships.
What data the vehicle feed must include
Google defines a technical specification for the vehicle feed with mandatory and optional attributes. Mandatory attributes are the bare minimum for a vehicle to be eligible for ads; 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 chassis number or an internal ID)title: Ad title. 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's detail page on the dealership's websiteimage_link: URL of the main vehicle image (minimum 400×300 px, recommended 800×600 or higher)price: Price of the vehicle with currency (e.g. "12500 EUR")availability: Status 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 of the vehiclemodel: Model of the vehicleyear: Year of manufacturemileage: Mileage (format: "85000 km")vin: Chassis number (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: Date of first registrationnumber_of_doors: Number of doorsengine_displacement: Engine capacity
The more optional attributes are completed, the better Google's ability to match the vehicle with specific and detailed searches ("blue automatic Golf TDI 2019"). To get 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 dealer management systems (DMS) with native integration with Google Merchant Center.
CSV (spreadsheet). Simpler to generate manually, but less efficient for large or high-turnover stocks. 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 that manage stock in spreadsheets and want to avoid the manual export and import step.
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 periodically downloads the feed (recommended for dynamic stocks). If you use a URL, Google can be configured to download the feed as frequently as you need: hourly, every 4 hours, 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): daily updates are the minimum. If you sell three or four cars a week, a daily update can leave you with active ads for cars sold the previous day for several hours. In this case, hourly or real-time updates are the most efficient option.
For dealerships with medium turnover (5-10 cars a month): daily updates are sufficient. Configuring Google Merchant Center to download the feed once a day, preferably in the early hours when there is less activity, ensures that the day's ads are up to date.
For dealerships with stable stock (less 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 make sure to update the feed that same day to avoid wasted clicks.
The practical rule 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 direct integration between the dealership's DMS and Google Merchant Center. With this integration, the feed is automatically updated every time a change in stock occurs: adding a new vehicle, price change, 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 the 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 as part of the platform: stock is automatically synchronised with Merchant Center without additional configuration by the dealership.
For dealerships that do not use a DMS with native integration, the alternative is to generate the feed from the current management system (in CSV or XML) and configure the periodic download 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 publishing, check out the article on multi-publishing cars for dealerships.
With Dealcar you can automatically synchronise your stock with Google VLA. More information at dealcar.io/dealcar-boost.
The most common feed errors in Merchant Center
Google Merchant Center validates the feed when it is uploaded and displays the errors that prevent certain vehicles from being approved for ads. These are the most common.
Images that do not meet the minimum requirements. Insufficient resolution (minimum 400×300 px), image with watermark, manufacturer's catalogue image instead of the actual vehicle, or broken image URL. Images are the first visual element of the ad and Google validates them with strict criteria.
To improve the quality of your vehicle photos both for the feed and for portals, you can review the 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 feed price matches the visible price on the vehicle's detail page. If there is a discrepancy, the ad is rejected. Make sure the price in the feed is exactly the same as the one appearing on that vehicle's page on the web.
Page URL not accessible or with error. If the vehicle's URL in the feed returns a 404 error or does not load correctly, the ad cannot run. This happens when a vehicle's page is deleted from the web without updating the feed.
Invalid or duplicate VIN. The chassis number must be unique for each vehicle and have the correct format (17 alphanumeric characters). If two vehicles have the same VIN in the feed (duplication 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 for inconsistency.
How to verify that the feed is working correctly
Once the feed is configured, three checks should be made regularly.
In Google Merchant Center: check the "Products" → "Product status" section weekly. Here it shows how many vehicles are approved, how many are under review, and how many are rejected, 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 synchronization problem.
Price verification. Periodically check that feed prices match those on the website detail pages, especially after massive price updates or price drops on cars that have been in stock for a long time.
To understand how to measure if feed changes are improving campaign performance, you can review 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 from the stock registered in the platform. When a car enters stock, it appears in the feed. When it is sold, it disappears. Prices and images are synchronised in real time. Without extra manual work, the feed is always up to date and VLA ads reflect the real state of the inventory.
If you want to see how it works, you can book 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 wider the variety of searches the campaign can cover. With fewer than 10 vehicles, coverage is very limited. From 20-30 cars onwards, the system starts to have enough variety to optimize itself.
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 euro car is lower than that of a 15,000 euro one. There is no explicit minimum price, but in practice very low-priced vehicles have lower visibility on 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 have different attribute specifications. The vehicle feed has sector-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 feed of the "Vehicles" type specifically for VLAs.
Table of Contents
Why the feed is the most critical factor in 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 in a VLA campaign
Unlike traditional search campaigns where the advertiser controls the keywords, in VLAs it is Google that decides which vehicle to display in each search based on the feed data. The quality and freshness of the feed directly determine the quality of the ads.
A well-structured 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 intent. Secondly, when the user reaches the vehicle's detail page, the information matches exactly what they saw in the ad (price, photos, availability), which reduces the bounce rate and increases conversion. Thirdly, the Performance Max algorithm can learn faster which vehicles generate conversions and optimize budget distribution.
An outdated feed has the opposite effect: ads for cars that have already been sold generating clicks without conversion, incorrect prices that build distrust, and an algorithm that cannot optimize because conversion signals are not consistent with the actual inventory.
To understand the full inner workings of VLAs before diving into feed synchronisation, you can review the complete Google Vehicle Ads guide for dealerships.
What data the vehicle feed must include
Google defines a technical specification for the vehicle feed with mandatory and optional attributes. Mandatory attributes are the bare minimum for a vehicle to be eligible for ads; 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 chassis number or an internal ID)title: Ad title. 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's detail page on the dealership's websiteimage_link: URL of the main vehicle image (minimum 400×300 px, recommended 800×600 or higher)price: Price of the vehicle with currency (e.g. "12500 EUR")availability: Status 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 of the vehiclemodel: Model of the vehicleyear: Year of manufacturemileage: Mileage (format: "85000 km")vin: Chassis number (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: Date of first registrationnumber_of_doors: Number of doorsengine_displacement: Engine capacity
The more optional attributes are completed, the better Google's ability to match the vehicle with specific and detailed searches ("blue automatic Golf TDI 2019"). To get 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 dealer management systems (DMS) with native integration with Google Merchant Center.
CSV (spreadsheet). Simpler to generate manually, but less efficient for large or high-turnover stocks. 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 that manage stock in spreadsheets and want to avoid the manual export and import step.
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 periodically downloads the feed (recommended for dynamic stocks). If you use a URL, Google can be configured to download the feed as frequently as you need: hourly, every 4 hours, 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): daily updates are the minimum. If you sell three or four cars a week, a daily update can leave you with active ads for cars sold the previous day for several hours. In this case, hourly or real-time updates are the most efficient option.
For dealerships with medium turnover (5-10 cars a month): daily updates are sufficient. Configuring Google Merchant Center to download the feed once a day, preferably in the early hours when there is less activity, ensures that the day's ads are up to date.
For dealerships with stable stock (less 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 make sure to update the feed that same day to avoid wasted clicks.
The practical rule 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 direct integration between the dealership's DMS and Google Merchant Center. With this integration, the feed is automatically updated every time a change in stock occurs: adding a new vehicle, price change, 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 the 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 as part of the platform: stock is automatically synchronised with Merchant Center without additional configuration by the dealership.
For dealerships that do not use a DMS with native integration, the alternative is to generate the feed from the current management system (in CSV or XML) and configure the periodic download 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 publishing, check out the article on multi-publishing cars for dealerships.
With Dealcar you can automatically synchronise your stock with Google VLA. More information at dealcar.io/dealcar-boost.
The most common feed errors in Merchant Center
Google Merchant Center validates the feed when it is uploaded and displays the errors that prevent certain vehicles from being approved for ads. These are the most common.
Images that do not meet the minimum requirements. Insufficient resolution (minimum 400×300 px), image with watermark, manufacturer's catalogue image instead of the actual vehicle, or broken image URL. Images are the first visual element of the ad and Google validates them with strict criteria.
To improve the quality of your vehicle photos both for the feed and for portals, you can review the 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 feed price matches the visible price on the vehicle's detail page. If there is a discrepancy, the ad is rejected. Make sure the price in the feed is exactly the same as the one appearing on that vehicle's page on the web.
Page URL not accessible or with error. If the vehicle's URL in the feed returns a 404 error or does not load correctly, the ad cannot run. This happens when a vehicle's page is deleted from the web without updating the feed.
Invalid or duplicate VIN. The chassis number must be unique for each vehicle and have the correct format (17 alphanumeric characters). If two vehicles have the same VIN in the feed (duplication 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 for inconsistency.
How to verify that the feed is working correctly
Once the feed is configured, three checks should be made regularly.
In Google Merchant Center: check the "Products" → "Product status" section weekly. Here it shows how many vehicles are approved, how many are under review, and how many are rejected, 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 synchronization problem.
Price verification. Periodically check that feed prices match those on the website detail pages, especially after massive price updates or price drops on cars that have been in stock for a long time.
To understand how to measure if feed changes are improving campaign performance, you can review 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 from the stock registered in the platform. When a car enters stock, it appears in the feed. When it is sold, it disappears. Prices and images are synchronised in real time. Without extra manual work, the feed is always up to date and VLA ads reflect the real state of the inventory.
If you want to see how it works, you can book 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 wider the variety of searches the campaign can cover. With fewer than 10 vehicles, coverage is very limited. From 20-30 cars onwards, the system starts to have enough variety to optimize itself.
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 euro car is lower than that of a 15,000 euro one. There is no explicit minimum price, but in practice very low-priced vehicles have lower visibility on 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 have different attribute specifications. The vehicle feed has sector-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 feed of the "Vehicles" type specifically for VLAs.
