2020 GMC Terrain · symptom sheet

Brake pedal goes hard or the booster or vacuum pump fails

54owner reports
86,000median miles
$800median quote
2involved a crash

Newest report Sep 23, 2026 · checked Sep 29, 2026

54 of the 71 reports of brake wear on the 2020 Terrain describe brake booster failure.

Part of Brakes grind, pulse or wear early (71 reports)

No recall on this systemas of Sep 29, 2026

2 crashesin 54 reports

Tick what matches of 54 reports

the pedal was hard to push

the brakes lost their power assist

the vacuum pump failed

it happened at low speed or when parking

there is a recall on it

Brake booster failure on other Terrain years

201851 reports 201954 reports 202054 reports

Report counts are for each model year on its own, so a newer car has had less time to collect them. Model years with too few reports of it for a sheet: 2014, 2015, 2016, 2017, 2026.

What this problem usually is

This is the narrower sheet inside brakes for reports about a hard pedal or a failed power assist. The pedal stops feeling normal: it turns stiff, takes far more force, and the car needs a longer distance to stop.

Read the full explainer · Which cars report it most

What got replaced

Owners who name the part that was replaced mention the vacuum pump (41 reports) and the brake booster (11 reports).

Recalls and investigations

No recall on the brakes covers the 2020 model year as of Sep 29, 2026.

What owners paid

15 of the 54 reports quote a price. Each dot is one quote. The middle half runs $295 to $1,400.

$295$800$1,400

$0k$2k$4k$6k$8k

When it happens

The middle half of failures fell between 53,000 and 110,501 miles, from the 24 reports that gave a mileage.

What owners wrote

“The brake suddenly became impossible to depress more than 3/4 of an inch. Almost unable to stop nearly hitting another vehicle. The dashboard then lit up with a "service brake system" warning. Luckily was only a few minutes from home brought it home and began the search for the issue. The brake vacuum pump failed. Unsure of further damage at this point. It being Sunday am unable to contact a shop or dealer.”
Filed Aug 23, 2026

“I was driving 55 miles an hour on an Expressway. And suddenly my truck just shut off.The brake became very hard unable to break very scary situation for me and my children. Engine power was reduced and would not start, many errors came up. The vacuum pump failed, which also caused the cam shafts to fail.The vacuum pump exploded into pieces and sent metal into my engine.”
Filed Mar 7, 2026

“Vacuum pump went out. It was a recall, previously on older models, but this model needs to”
Filed Nov 13, 2025

“SERVICE BRAKE ASSIST CAME ON, CHECK ENGINE LIGHT CAME ON AND VEHICLE WAS HARD TO STOP. Took to authorized service dealer and all parts were replaced. After driving it for a little while, SERVICE BRAKE ASSIST BACK ON, CHECK ENGINE LIGHT BACK ON AND VEHILCE IS HARD TO STOP.”
Filed Oct 30, 2025

Should you keep driving it?

This page can't tell you that. 2 of 54 reports involved a crash. Owners who file are the ones who had a bad experience, and nobody checks their reports. If the problem affects steering, braking, power or a fire risk, treat it as a safety fault and have it inspected before a long or high-speed drive.

File your own report with NHTSA. Complaint counts are how a problem gets an investigation. How reports land on this sheet.

Guide Taking it to a shop? How to describe this problem so it gets found