Inventory Feed Syndication Explained: DMS → Facebook → Google

Inventory syndication is one of those topics every vendor assumes you understand and nobody explains. If you have ever wondered why your website shows a car that Facebook doesn't, or why a sold vehicle is still live on Cars.com, the answer is almost always in the syndication pipeline.

Here is how it actually works, in plain language.

Start at the source: your DMS

Your Dealer Management System (DMS) — CDK, Reynolds, Dealertrack, DealerCenter, Frazer, VinSolutions-integrated systems, and others — is the single source of truth for your inventory. Every vehicle on your lot should be entered here first, with:

• VIN, year, make, model, trim

• Mileage, condition, photos

• Pricing (retail, internet, sale)

• Stock number

• Status (available, sold, on hold, in transit)

• Location (if multi-rooftop)

• Purchase date (cost basis, age calculations)

If a vehicle is not in the DMS, it shouldn't be anywhere else. If it is in the DMS and missing from a downstream channel, your feed is broken.

The inventory feed

Your DMS (or your website provider) generates a structured feed — typically an XML or CSV file — that downstream channels can read. Common feed formats:

• AutoTrader feed spec (XML)

• Cars.com feed spec (XML)

• Facebook Vehicles feed spec (CSV or XML)

• Google Vehicle Ads feed spec (TSV or XML)

• Custom website feeds (varies by provider)

Each has slightly different required fields. A good inventory feed provider normalizes data across all of them, so you don't have to maintain 5 separate feeds.

Feed format technical details

Facebook Vehicles feed (the one that matters for Marketplace):

Required fields include:

• vehicle_id (unique per vehicle, typically VIN)

• title (year, make, model, trim)

• description (100 to 150 words)

• url (link to VDP)

• image_url (up to 20, comma-separated)

• price (in major currency units)

• availability (in stock, out of stock)

• condition (new, used, CPO)

• mileage

• vin

• year, make, model, trim

• body_style

• transmission, drivetrain, fuel_type

• exterior_color, interior_color

• dealer_address, dealer_city, dealer_state, dealer_zip

Missing any of these causes the listing to fail validation. Inconsistent values (blank mileage, misspelled make) can reduce distribution.

Google Vehicle Ads feed: similar structure but with different field names and stricter image requirements. Your provider handles the translation.

Downstream destinations

The inventory feed typically gets pushed to:

1. Your website (VDPs and inventory pages)

2. Third-party marketplaces (Cars.com, AutoTrader, CarGurus)

3. Facebook Marketplace (via approved Inventory Partner)

4. Google Business Profile (via Products or approved partner)

5. Google Vehicle Ads (paid inventory advertising)

6. OEM co-op tools (for franchise dealers)

7. Email marketing platforms (featured inventory campaigns)

8. Retargeting pixels (Facebook Pixel, Google Remarketing)

Each has different sync frequencies and data requirements.

The synchronization problem

Inventory changes constantly. Every sold vehicle, price drop, new arrival, and photo update triggers downstream updates. The question is how fast:

• Real-time sync: within minutes of DMS change

• Hourly sync: up to 60-minute delay

• Daily sync: up to 24-hour delay

• Weekly sync: up to 7-day delay (unacceptable for modern dealer ops)

For Marketplace and GBP, daily is usually enough. For Cars.com and AutoTrader, faster is better — buyers get annoyed when they inquire about a vehicle that sold yesterday.

Common failure points

1. Feed breaks and nobody notices

The DMS provider changes an export format. No cars update for a week. Your partner should alert you when the feed stops flowing. Most don't.

Fix: establish a weekly "feed health" check with your partner. Are new arrivals appearing? Are sold units disappearing? If either is failing, escalate immediately.

2. Photos don't syndicate

Different feed specs handle photos differently. Some require URLs, some require dimensions, some cap the count. A partner that silently drops photos will tank your engagement.

Fix: spot-check 5 random vehicles weekly. Does each have 15+ photos on every channel?

3. Sold vehicles linger

If status changes in your DMS don't flow fast, sold units stay live. Buyers inquire, BDC wastes time, dealership looks disorganized.

Fix: verify sold-vehicle removal time with your partner (should be under 24 hours). Test this by marking a vehicle sold in the DMS and timing how long until it comes down.

4. Pricing mismatches

If your DMS has $22,995 but your Marketplace listing says $24,495, you just lost trust before the conversation starts.

Fix: weekly sample audit of 10 random vehicles across all channels. Any mismatches mean a feed issue or manual override somewhere.

5. Duplicate listings

When two feeds push the same vehicle to the same channel, Facebook and Google penalize the account. Often happens when a DMS and a website provider both push to the same destination.

Fix: designate one authoritative source per channel. If your website provider pushes to Facebook, your standalone partner shouldn't.

6. Title truncation

Facebook and Google have title length limits. Long titles get cut off, losing the trim or key feature.

Fix: ask your partner what title format they use. "2022 Toyota RAV4 XLE AWD" is better than "TOYOTA 2022 RAV4 XLE AWD - CLEAN CARFAX - ONE OWNER."

7. Field mapping errors

VIN in the wrong column, mileage as a string instead of integer, etc. Causes silent failures.

Fix: review the field mapping document with your partner at onboarding. Don't assume it is correct.

DMS-specific notes

CDK

• Strong feed infrastructure, clean data.

• Some third-party exports require premium modules.

• Typical sync frequency: real-time to hourly.

Reynolds and Reynolds

• Similar to CDK in capability.

• Historically restrictive on third-party integration — check with your account manager.

• Typical sync frequency: hourly.

Dealertrack

• Flexible, integrates well with most inventory partners.

• Multi-rooftop support is strong.

• Typical sync frequency: hourly.

DealerCenter

• Popular with independent dealers.

• Direct Facebook Marketplace integration available.

• Typical sync frequency: daily to hourly.

Frazer

• Small-dealer focused.

• Limited feed options; often requires website provider as an intermediary.

• Typical sync frequency: daily.

Multi-rooftop considerations

If you run 3+ rooftops:

• Centralize inventory at the group level in your DMS.

• Tag each vehicle with its physical location.

• Ensure each Facebook Page and GBP maps to the correct rooftop.

• Don't cross-list vehicles across rooftop feeds (creates duplicates).

• Monthly audit: does each rooftop's Facebook Page show only that rooftop's inventory?

What good syndication looks like

• One feed from DMS → one partner → multiple channels

• Real-time or near-real-time sync

• Automatic sold-unit removal

• Photo optimization per-channel

• Breakage alerts (proactive, not reactive)

• Reporting on what is live where

• Weekly health audits

• Clean attribution back to sales

Troubleshooting guide

Problem: New arrival not showing up on Marketplace.

Diagnosis steps:

1. Confirm vehicle is active in DMS.

2. Confirm vehicle has all required fields (photos, description, price, VIN).

3. Check partner dashboard for posting queue (may be waiting for daily limit).

4. Check Facebook Page Commerce Manager for listing status.

5. If still missing after 48 hours, escalate to partner support.

Problem: Sold vehicle still live on Cars.com after 3 days.

Diagnosis:

1. Confirm status changed to "sold" in DMS.

2. Check website feed export — is it showing as sold?

3. Check Cars.com feed ingestion log with account manager.

4. Force a feed resync.

Problem: Pricing different across channels.

Diagnosis:

1. Which price is correct (DMS authoritative)?

2. Check each channel's price source (direct from DMS feed or website feed).

3. Look for manual overrides in any channel's admin panel.

4. Sync all to DMS source.

Where Localshift sits

Localshift reads your existing inventory feed (wherever it lives — DMS, website provider, or custom API) and handles syndication to Facebook Marketplace, Google Business Profile, and Instagram Shopping. Sold units come down automatically within 24 hours. Price drops push instantly.

If you have Cars.com and AutoTrader already covered by your website provider, we slot in alongside — not instead of — to add the channels they don't cover. One integration, multiple surfaces live.