Type two searches into Google's Keyword Planner and compare. Drivers look for an oil change near them roughly 1.5 million times a month across the US, and the priciest top-of-page bids stop at $6.80. They look for brake repair near them about 74,000 times, with bids topping out at $8.50. The oil change search is twenty times bigger and cheaper at the top of the page.
Now hand both to a campaign whose job, in Google's words, is to "get the most conversions for your campaign while spending your budget." Every booking counts as one conversion. An oil change booking and a brake booking look identical to it. Our reading of what happens next: the campaign fills the calendar with whatever it can book most cheaply, and in most markets that's the oil change.
That isn't automatically bad. Chapter 3 made the case that a coupon oil change is the cheapest way to meet a car that will need brakes and tires later. But it should be a choice the shop makes, not one Google makes for it. Performance Max is the campaign where that choice gets made, mostly by deciding what it's pointed at. Chapter 9 set up Search; this chapter adds the campaign Google pushes hardest, and keeps it aimed at the jobs the shop wants.
Performance Max Waits Until Search Books 30 Cars a Month, Month After Month
Think of Performance Max as a single campaign with keys to every room Google rents out: YouTube, Display, Search, Discover, Gmail and Maps, by Google's own list. The shop hands over goals, a budget, pages, text, photos and video. Google decides which room each dollar goes to.
That's exactly why it comes late. A campaign that decides everything for itself learns only from the conversions it can see. In a new account there aren't many, and the ones there are may be messy. So Performance Max waits until Search is booking cars reliably: at least 30 quality conversions a month, sustained, with both Isolation and Exploration running. A typical shop crosses that line in the second half of its first year. Shops spending more cross it faster.
Before it launches, check what it would learn from. If Chapter 1's tracking still counts directions clicks or text-club sign-ups as primary conversions, Performance Max will go find more of those. Clean the conversion list first. And give Performance Max its own budget, money the shop can afford to test with. Keep it on a separate budget, not a shared one, and keep Isolation funded so it never shows "limited by budget." If it does, Performance Max inherits Isolation's brake searches. Start it small, judge it on what lands in the bays over a couple of months, and grow it only from there.
Google Built Performance Max to Get the Most Bookings for the Budget. The Cheapest Ones Count the Same.
In our build, Performance Max launches on conversions, not conversion value, and with no target cost per booking at first. It needs room to learn. A target comes later, once the campaign has its own history to set it from, the same way Exploration's target came from Isolation's real costs in Chapter 7.
That setup has a consequence worth saying out loud. Maximize conversions counts bookings. It doesn't know that a brake job pays the shop more than an oil change, unless the account tells it, and at launch ours doesn't. So the cheapest booking it can find is, to the campaign, the best one.
A shop has three ways to steer that, and none of them requires guessing what Google's systems are thinking:
- Choose the goals. Google's campaign-specific goals let one campaign "override your account-default goals and specify which goals you'd like to track in your conversion reporting and use for bidding." If the shop's booking tool can tell repair bookings from maintenance-only bookings, Performance Max can bid on the first and simply report the second.
- Choose the pages. The next section.
- Choose the services it advertises. Asset groups, search themes and images built around brakes, transmission and the makes the shop knows tell Performance Max what the shop wants more of.
If the shop wants more oil changes, because its returning customers turn into brake jobs, all three can point the other way. Either way, the shop decides.
Then watch what it books. Performance Max has its own search terms report, and Google's insights page groups what the campaign showed up for. Read both weekly for the first month. Ask the front counter, too: are the new bookings brake jobs and diagnostics, or a run of coupon oil changes? If it's the coupons and the shop wanted repairs, tighten the asset groups, exclude the coupon page and give it a month. If the coupons come back as brake jobs six months later, Chapter 3's math says the campaign is doing its job.
Final URL Expansion Arrives Switched On, and It Lets Google Pick the Landing Page
Final URL expansion lets Performance Max send a click to any page on the shop's site it judges a better match, not just the page you chose. Google switches it on for every new Performance Max campaign, and its own help page admits the side effect: without exclusions, ads can land on pages you never meant them to.
In a repair account, the unintended page is easy to predict. Half the shops we profiled ran dollar coupons, most often on brake service, and four of the twelve put an oil change deal on their specials pages. A campaign hunting the cheapest bookings, free to choose its own landing page, has every reason to find the coupon page.
There are two fixes, and most repair accounts use both:
- Exclude the pages that shouldn't get ad traffic: coupons if you don't want coupon customers from this campaign, careers, the blog, the privacy policy. Google puts the URL exclusions under the campaign's asset optimization settings.
- Build one asset group per job. A brake asset group with the brake page as its final URL, brake headlines and photos of the brake bay. A transmission group. A group for the make the shop knows best. Chapter 4 already built those pages for Search.
If the site is small or the pages are thin, turn final URL expansion off entirely. It can always come back on once the account knows which pages book cars.
A Driver Who Types Your Exact Brake Keyword Gets Your Search Ad, Not Performance Max
Shops worry that Performance Max will swallow the Search campaign they spent six months tuning. Google's rules say otherwise for the searches that matter most. If a driver types [brake repair near me] and that exact phrase sits in brackets in your Isolation campaign, Google hands the search to Isolation, as long as that keyword is eligible to show: approved ads, an approved page, and a campaign that isn't limited by budget. Under those conditions, Google's priority rules put phrase keywords, broad keywords and Performance Max behind it.
So "brake repair near me," typed exactly, still goes to the Isolation keyword with its hand-set bid. On every other search, Performance Max competes with Exploration's broad keywords, and the stronger Ad Rank wins. It also reaches the places Search never goes: the long-tail searches Exploration hasn't reached, YouTube, Maps, Gmail and the rest.
Two settings keep it in its lane:
- Brand exclusions. Add the shop's own name as a brand exclusion so Performance Max stays off those searches. The brand campaign from Chapter 2 already answers them.
- Location: Presence, the same as Chapter 9. Performance Max reaches the whole map if you let it.
Search themes are the third lever. They're short phrases that tell Performance Max which searches to look for, and they work best when they describe the jobs the shop wants: "transmission rebuild," "European car repair," "brake job," not "car service."
Real Shop Photos Feed Performance Max. Stock Photos Starve It.
Performance Max builds ads from whatever you hand it, across places Search never reaches: a YouTube video, a banner on a news site, a card in Gmail. That makes the raw material matter more than in any other campaign.
- Headlines and descriptions: start with the Search headlines that already won in Chapter 8. They've been tested on real drivers in your town.
- Photos: real ones. The bays, the techs, a car on the lift, the front counter, the sign out front. A stock photo of a smiling mechanic in a spotless garage looks like every chain's ad, and drivers have learned to scroll past it.
- Video: shoot something, even 20 seconds on a phone walking through the shop. Google's own settings page lists auto-generated video as on by default: "If you don't have your own video, Google AI will generate a video using your existing Performance Max campaign assets." A slideshow of your logo isn't what you want representing the shop on YouTube.
- AI-generated text and images: skip them. The point of Chapter 8 was to sound like the shop's own customers.
Then give it hints about who to look for. Audience signals don't fence the campaign in, but they tell it where to start. A custom segment is a description of the driver you want, written in keywords, web addresses and apps. Feed it the repair searches from Chapter 5 and the sites of the chains and dealers your customers compare you with. Add the shop's own customer list too, so the campaign can learn what an existing customer looks like.
Late, aimed and fed real material: that's how our Google Ads management team brings Performance Max into a repair account once the account has earned it.
Next: Google's Car-Brand Audiences Are Shopping for a Car. "Auto Repair & Maintenance" Is Shopping for a Shop.
Those audience signals deserve a closer look. Chapter 11 opens Google's audience lists and shows which ones describe drivers who need a mechanic, and which ones describe drivers who want a new car.
This chapter is part of Google Ads for Auto Repair, a sixteen-chapter guide for independent repair shops in every state.
