The 2021 Mustang is largely solid but the MT82 manual transmission remains problematic, EcoBoost engines show ring land failures under boost, and the 10R80 automatic has documented harsh shift quality issues. GT500s with the Predator engine are holding up well so far but sample size is limited.
MT82 Manual Transmission Synchro Wear and Lockout Issues
Common · medium severity
Typical onset: 40,000-80,000 mi
Symptoms: 3rd-4th gear grind during upshifts especially when warm, Gear lockout requiring clutch cycle to engage, Notchy gate feel even with fresh fluid, Reverse gear grind on engagement
Fix: MT82 rebuild with updated brass synchro rings and detent springs, 8-12 hours labor. Some shops recommend Tremec TR-3160 swap instead at similar cost. Ford extended warranty covered some early cases but 2021s are aging out.
Estimated cost: $2,800-4,200
2.3L EcoBoost Piston Ring Land Failure
Occasional · high severity
Typical onset: 50,000-90,000 mi
Symptoms: Excessive oil consumption beyond 1 qt per 1,000 mi, Blue smoke on cold start or under boost, Loss of compression on cylinder 3 or 4 most common, Misfires under load with no obvious ignition fault
Fix: Ring land cracks from detonation or high boost. Requires short block replacement or full engine rebuild with forged pistons if modified. 16-20 hours labor plus machine work if rebuilding. Ford has denied many warranty claims citing 'abuse' if tuned.
Estimated cost: $5,500-8,500
10R80 Automatic Transmission Harsh Shifts and Shudder
Common · medium severity
Symptoms: Hard 2-3 or 3-4 upshift especially at part throttle, Shudder during torque converter lockup 35-45 mph, Delayed engagement into drive from park when cold, Occasional limp mode with P0777 solenoid code
Fix: Often requires valve body replacement and adaptive learning reset. TSB 21-2351 addresses some cases with software flash. Torque converter replacement needed if shudder persists after fluid service. 4-6 hours for valve body, 10-14 for converter.
Estimated cost: $1,800-4,500
Transmission Oil Cooler Line Leaks
Occasional · medium severity
Typical onset: 60,000-100,000 mi
Symptoms: Transmission fluid pooling under vehicle near radiator, Pink residue on cooler lines at quick-connect fittings, Low fluid level on dipstick with no visible external leak elsewhere, Transmission running hotter than normal
Fix: Steel lines rust through at bends or quick-connects fail from heat cycling. Replace affected line section and flush cooler if contaminated. 2-3 hours labor. Check both supply and return lines while in there.
Estimated cost: $400-750
BCM Body Control Module Electrical Gremlins
Occasional · low severity
Symptoms: Intermittent no-start with no crank, resolves after 10-15 minutes, Dash lights flicker or cluster reboots while driving, SYNC system freezes or reboots randomly, Door locks cycle on their own or fail to unlock
Fix: Two recalls issued for BCM software. Reflash per TSB or BCM replacement in persistent cases. Ford updated BCM part number twice for 2021 model year. 1.5-2 hours for programming, 3-4 if module replacement needed.
Symptoms: Rattling noise at idle with clutch engaged, goes away when depressed, Vibration through drivetrain during acceleration, Clutch pedal chatter during engagement, Metallic clunking when letting off throttle in gear
Fix: Dual-mass flywheel springs fail or crack. Replace with OEM dual-mass or upgrade to single-mass billet unit. Requires transmission removal. Do clutch at same time. 7-9 hours labor total.
Estimated cost: $1,600-2,800
Owner tips
MT82 transmission: use Motorcraft XT-M5-QS fluid, change every 30k mi, avoid hard 1-2 shifts when cold
10R80 automatic: service fluid every 40k mi despite 'lifetime fill' claim, use Mercon ULV only
EcoBoost owners: stay on 93 octane, monitor oil consumption monthly, avoid aggressive tuning without supporting mods
Check transmission cooler lines annually for rust if you're in salt states — cheap insurance against a tow
Buy a V8 automatic or pass on the MT82 manuals unless you're prepared for a transmission rebuild; EcoBoost is solid if kept stock on premium fuel.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.
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ELECTRICAL SYSTEM:BODY CONTROL MODULE/BCM · 25V689000
2025-10-10
Ford Motor Company (Ford) is recalling certain 2021-2023 Mustang vehicles repaired incorrectly under recall number 23V727. The brake fluid level sensor may not activate the visual warning indicator when the brake fluid is low. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 135, "Light Vehicle Brake Systems."
Consequence: Without a low brake fluid warning light, the vehicle may be driven with low brake fluid, reducing braking performance and increasing the risk of a crash.
Remedy: Dealers will update the body control module software, free of charge. Owner notification letters were mailed December 11, 2025. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25C55. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on NHTSA.gov beginning November 17, 2025.
Ford Motor Company (Ford) is recalling certain 2021-2023 Bronco, Explorer, Lincoln Aviator, F-250 SD, F-350 SD, F-450 SD, F-550 SD, 2021-2022 Lincoln Navigator, Mustang, F-150, and 2022 Expedition vehicles. The low-pressure fuel pump may fail, which can result in an engine stall while driving.
Consequence: An engine stall increases the risk of a crash.
Remedy: The remedy is under development. Interim notification letters notifying owners of the safety risk were mailed July 16, 2025. Second letters will be sent once the remedy is available, anticipated 2nd Quarter 2026. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25S75.
BACK OVER PREVENTION:SOFTWARE · 25V442000
2025-06-27
Ford Motor Company (Ford) is recalling certain 2018-2022 Transit Connect, 2019-2020 MKZ, MKX, Edge, Continental, F-150, Nautilus, Fusion, 2019-2023 Ranger, Mustang, 2020-2021 EcoSport, Expedition, Navigator, 2020-2022 Escape, F-250 SD, Corsair, 2020-2023 Aviator, Transit, 2020-2024 Explorer, 2021-2024 Bronco Sport, and 2022-2024 Maverick vehicles. A software error may cause the rearview camera to display a blank image, or the image may remain on the display after the backing event has ended.
Consequence: A rearview camera that displays a blank image can reduce the driver's view behind the vehicle. A rearview image that continues to be displayed after the vehicle is shifted out of reverse may distract the driver. Both of these situations can increase the risk of a crash.
Remedy: Dealers will update the rearview camera software, free of charge. Owner notification letters were mailed September 4, 2025. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25S72.
ELECTRICAL SYSTEM:BODY CONTROL MODULE/BCM · 23V727000
2023-10-27
Ford Motor Company (Ford) is recalling certain 2020-2023 Mustang vehicles. The brake fluid level sensor may not activate the visual warning indicator when the brake fluid is low. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 135, "Light Vehicle Brake Systems."
Consequence: Without a low brake fluid warning light, the vehicle may be driven with low brake fluid, reducing braking performance and increasing the risk of a crash.
Remedy: Dealers will update the body control module software, free of charge. Owner notification letters were mailed December 21, 2023. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 23C35.
AIR BAGS:KNEE BOLSTER · 22V083000
2022-02-16
Ford Motor Company (Ford) is recalling certain 2021-2022 Mustang vehicles. An insufficient weld on the front passenger knee air bag may result in an improper air bag deployment.
Consequence: An improper air bag deployment can increase the risk of injury during a crash.
Remedy: Dealers will replace the front passenger knee air bag, free of charge. Owner notification letters were mailed on March 8, 2022. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 22S07.
AIR BAGS:SIDE/WINDOW:CURTAIN · 21V980000
2021-12-16
Ford Motor Company (Ford) is recalling certain 2021 Mustang vehicles. The side curtain air bag inflators may have been manufactured with the incorrect amount of compressed gas, which can result in improper air bag inflation. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard numbers 226, "Ejection Mitigation," and 214, "Side Impact Protection."
Consequence: An air bag that does not inflate properly can increase the risk of injury in a crash.
Remedy: Dealers will replace the side curtain air bags, free of charge. An interim owner notification letter was mailed on February 3, 2022. Owner notification letters were mailed on April 22, 2022. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 21C37.
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