2021 Ford Bronco Sport Problems

What owners report

Complaints on the 2021 Bronco Sport cluster around sudden loss of power or stalling, rear brake noises in reverse, and shuddering or grinding from the transmission and rear driveline, with many reports filed between roughly 20,000 and 80,000 miles. A separate group of early-mileage complaints describes squealing or grinding rear brakes, and several owners link electrical and stalling symptoms to recalls for the 12-volt battery and control module software.

1. 1
   Brakes

   Rear brakes squeal, grind or moan in reverse

   • 79 complaints (11%)
   • median 6,491 mi at 1.4 yrs old (30 state mileage)
   • 2 mention a crash, fire or injury
   • filed 2021–2026

   Complaints describe a loud squeal, grinding, moan, or horn-like sound from the rear brakes, most often when reversing at low speed or right after a cold start. Several owners say the dealer replaced pads or calipers and the noise came back, and some were told it was a known issue without a fix offered. Some complaints also note reduced braking feel or longer stopping. Mostly under 25,000 miles, often on the first reverse of the day or during low-speed reversing.

   Recall 21V922000

   What to check: Reverse the vehicle cold and listen for squeal or grinding, and ask for brake service records. Check whether the rear brake lining recall (21V922000) applies to the VIN and was performed.

   2 excerpts from owner complaints in NHTSA records

   “The contact owns a 2021 Ford Bronco Sport. The contact stated while reversing and depressing the brake pedal, there was a loud squealing sound coming from the vehicle. The vehicle was taken to the local dealer who was unable to determine the cause of the failure. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 2,000.”

   NHTSA complaint #11569198, filed 2024-02, 2,000 miles

   “The contact owns a 2021 Ford Bronco Sport. The contact stated that while reversing and depressing the brake pedal, there was a loud sound like a horn coming from the rear brakes. The vehicle was taken to the local dealer who replaced the brake calipers, but the failure persisted. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was 10,000.”

   NHTSA complaint #11516826, filed 2023-04, 10,000 miles
2. 2
   Electrical system

   Battery drain, no-start and charging warnings

   • 232 complaints (33%)
   • median 42,000 mi at 3.9 yrs old (85 state mileage)
   • 10 mention a crash, fire or injury
   • owner-quoted repair $900 (median of 17 quotes)
   • filed 2021–2026

   Owners report a no-start or dead battery, blank cluster, low or faulty charging system messages, and screens going blank or announcing system-off-to-save-battery. Several say the battery was replaced and the problem returned, and some link the symptoms to the 12-volt battery or control module recalls. Others report stalled engines or inoperative electrical features such as hazard lights once power is lost. Spread from about 15,000 to 75,000 miles, often on startup, after short trips, or when stopped in traffic.

   Recall 25V019000Recall 24V267000Recall 25V158000Recall 25V4420002 related service bulletins

   What to check: Ask for the battery replacement date and whether the 12-volt battery and control module recalls and software updates were completed. Check for aftermarket or recently replaced batteries that suggest repeat drain issues.

   2 excerpts from owner complaints in NHTSA records

   “The contact owns a 2021 Ford Bronco. The contact stated that while driving at 80 MPH, a warning message displayed reading Service charging system soon , after which the infotainment system intermittently functioned properly. No warning lights were illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the alternator harness. The vehicle was repaired. …”

   NHTSA complaint #11628918, filed 2024-12, 36,000 miles

   “The contact owns a 2021 Ford Bronco Sport. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power, stalled, and then failed to restart. The loss of power train message was displayed. The vehicle was towed to the local dealer where it was diagnosed that the battery and control module needed to be reprogrammed. The vehicle was repaired. The manufacturer was not contacted. …”

   NHTSA complaint #11514767, filed 2023-03, 3,500 miles
3. 3
   Engine

   Stalling or sudden loss of power while driving

   • 153 complaints (21%)
   • median 41,713 mi at 3.8 yrs old (56 state mileage)
   • 3 mention a crash, fire or injury
   • owner-quoted repair $800 (median of 10 quotes)
   • filed 2021–2026

   Owners describe the engine cutting out at stop lights, in traffic, or at highway speed, sometimes with multiple warnings across the instrument panel and no ability to restart. Some report that the vehicle goes into park and cannot be shifted to neutral, leaving them unable to push it clear. Dealers variously found a bad battery, a turbocharger fault, a fuel delivery problem, or performed software updates, and some owners say the stall recurred after repair. Reported from under 100 miles to about 100,000 miles, seen at stop lights, low-speed maneuvering, and highway speeds.

   Recall 25V019000Recall 24V267000Recall 25V158000Recall 21V6250001 related service bulletin

   What to check: Ask whether the 12-volt battery and body/powertrain control module recalls were completed, and whether any stall was diagnosed and documented. A history of repeat no-start or stall repairs is worth weighing.

   2 excerpts from owner complaints in NHTSA records

   “While driving the vehicle the warning system activated and the entire car shut down. I was stranded in an intersection of a busy street during a heavy traffic period. I was unable to start the vehicle, use my hazards, or put the car in neutral to push it to a safe location.”

   NHTSA complaint #11506114, filed 2023-02, 36,101 miles

   “this has happened twice to me. First time, I was driving around a roundabout - and the engine kicked off and there were a lot of alerts across the screen. I was safely able to coast off the road and onto the side where I sat for a little bit trying to restart it. After pushing the start button several times - it started back up and I was on my way. Most recently, last week - I was driving on the highway and the engine died and so many alerts were going across the screen. …”

   NHTSA complaint #11502129, filed 2023-01, 3,000 miles
4. 4
   Transmission and drivetrain

   Transmission shudder, harsh shifts and failure to engage

   • 165 complaints (23%)
   • median 49,000 mi at 3.8 yrs old (53 state mileage)
   • 7 mention a crash, fire or injury
   • owner-quoted repair $6,464 (median of 17 quotes)
   • filed 2021–2026

   Owners report shuddering at low speed, jerky or unintended gear changes, and messages such as powertrain malfunction or inability to engage park. Some vehicles would not exceed low speed or high RPM, and dealers in some cases replaced the transmission or a failed lead frame. Others describe all-wheel-drive chatter while turning at low speed. Commonly between about 30,000 and 136,000 miles, at low speeds and while turning or accelerating from a stop.

   Recall 25V158000Recall 24V2670006 related service bulletins

   What to check: Test drive at low speed including tight turns and listen for shudder or chatter, and ask whether transmission or AWD module software bulletins were applied.

   2 excerpts from owner complaints in NHTSA records

   “Not even 200 miles, engine began rattling and stalling out. I was stranded in the middle of the road at a green light. Dealership claims torque converter problem. Brand new badlands package. 2 liter 4cyl ecoboost 250hp”

   NHTSA complaint #11414378, filed 2021-04, 198 miles

   “The contact owns a 2021 Ford Bronco Sport. The contact stated that while driving 30 MPH, the contact attempted to accelerate; however, the transmission failed to shift into a higher gear. The contact stated that the RPM was high and the vehicle was restarted to continue driving. The messages Power Train Malfunction and Cannot Engage in Park, Turn on Parking Brake were displayed. …”

   NHTSA complaint #11770167, filed 2026-10, 97,434 miles
5. 5
   Transmission and drivetrain

   Rear differential noise, grinding or wheel drag

   • 78 complaints (11%)
   • median 43,000 mi at 3.5 yrs old (33 state mileage)
   • 2 mention a crash, fire or injury
   • filed 2021–2026

   Complaints describe grinding, screeching, or shuddering from the rear while turning or reversing, and in some cases the rear wheels seizing or losing traction. Dealers diagnosed rear differential fluid contamination or a failed rear end and recommended replacement or a fluid and vent tube service. Some owners mention a rear drive unit lubricant recall but were told their VIN was not included. Reported from about 5,000 to over 125,000 miles, often during turns, reversing, or parking maneuvers.

   Recall 21V011000

   What to check: Listen for rear-end grinding or howling on a slow turning test drive, and check whether the rear drive unit lubricant recall (21V011000) applies and was completed.

   2 excerpts from owner complaints in NHTSA records

   “The contact's daughter owns a 2021 Ford Bronco Sport. The contact stated while the driver was driving at various speeds, the rear end of the vehicle made an abnormal grinding sound and shuddered. The vehicle was taken to the dealer, where it was determined that the rear differential unit fluid needed to be replaced and a vent tube needed to be installed in the rear differential unit. The vehicle was not repaired. The dealer informed the contact that the repair would be covered. …”

   NHTSA complaint #11583860, filed 2024-04, 5,000 miles

   “The contact owns a 2021 Ford Bronco Sport. The contact stated that while attempting to reverse(R), the vehicle made an abnormal grinding metallic sound. No warning lights were illuminated. The vehicle was taken to the dealer, where it was diagnosed with rear end fluid metal contamination. The vehicle was not repaired. The contact researched and related the failure to NHTSA Campaign Number: 21V011000 (Power Train). The dealer confirmed that the vehicle was not included in the recall. …”

   NHTSA complaint #11590658, filed 2024-05, 125,000 miles

Buying note. Have a pre-purchase inspection include the rear brakes, rear differential and transmission behavior on a slow turning drive, and confirm all open recalls for the 12-volt battery, control module software, fuel injector and rear brake lining were completed. Service records showing repeated stall or no-start visits are worth reviewing closely.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.