The 2021 Tundra sits at the tail end of a platform that ran 2007-2021, meaning most design kinks were ironed out, but aged tech means it shares problems with older siblings. The 5.7L 3UR-FE is bulletproof when maintained, but several systemic issues persist.
Secondary Air Injection Pump Failure
Common · medium severity
Typical onset: 60,000-100,000 mi
Symptoms: Check engine light with P0418/P0419/P2440 codes, Rough cold-start idle for first 30 seconds, Failed emissions testing
Fix: Replace air injection pump and/or combination valve assembly. 2-3 hours labor. Pumps seize from moisture ingress or simply wear out. Not a breakdown issue but kills emissions compliance.
Estimated cost: $800-1,400
Transmission Oil Cooler Line Corrosion
Common · high severity
Typical onset: 70,000-120,000 mi
Symptoms: Transmission fluid leaking near radiator, Pink fluid puddles under front of truck, Low transmission fluid level triggering slipping or limp mode
Fix: Steel cooler lines rust through where they pass behind crossmember, especially in salt states. Replace both lines (they come as a pair). 3-4 hours labor plus fluid. Ignoring this grenades the transmission when it runs dry.
Estimated cost: $600-1,100
Exhaust Manifold Crack and Stud Failure
Occasional · medium severity
Typical onset: 80,000-150,000 mi
Symptoms: Ticking noise from engine bay on cold start that fades as engine warms, Exhaust leak smell in cabin with heat on, P0420 catalyst efficiency code in some cases
Fix: Manifolds crack at the collector or studs break off in the head. Extraction of broken studs adds 2-4 hours. Full job: 6-8 hours for both banks if doing it right. OE manifolds will crack again; aftermarket headers solve it permanently but cost more.
Estimated cost: $1,800-3,200
Power Steering Rack Leaks
Occasional · medium severity
Typical onset: 90,000-140,000 mi
Symptoms: Power steering fluid dripping from rack boots, Groaning or whining when turning at low speed, Steering wheel requires more effort when cold
Fix: Rack seals fail, often at inner tie rod boots. Rebuilding racks isn't cost-effective; most shops replace the entire unit. 4-5 hours labor plus alignment. There was a recall for faulty racks on some units, check VIN eligibility first.
Estimated cost: $1,200-2,000
Rear Driveshaft Carrier Bearing Failure
Occasional · medium severity
Typical onset: 100,000-160,000 mi
Symptoms: Rumbling or droning noise from under cab at highway speeds, Vibration felt through floor at 55-70 mph, Noise changes with throttle application/deceleration
Fix: Two-piece driveshaft uses a center support bearing that wears out. Replace bearing and rubber mount. 2 hours labor. If ignored, imbalance can damage transmission output shaft seal or yoke.
Estimated cost: $400-700
Brake Master Cylinder Slow Internal Leak
Rare · high severity
Typical onset: 120,000+ mi
Symptoms: Brake pedal slowly sinks to floor when holding steady pressure at stop, No external fluid leaks visible, Brakes work fine initially but pedal feels spongy over time
Fix: Internal seal bypass allows pressure to bleed down. Must replace master cylinder and bench-bleed before install. 2-3 hours including system bleed. Rare but dangerous when it happens.
Estimated cost: $500-850
Fuel Pump Assembly Failure (Rust-Belt Trucks)
Occasional · high severity
Typical onset: 90,000-130,000 mi
Symptoms: No-start or intermittent stalling after sitting overnight, Check engine light with P0230 or P0231 codes, Fuel gauge erratic or stuck
Fix: Pump module corrodes internally from water intrusion via rusted tank seams or vent lines in salt states. Drop tank, replace entire assembly including sender and filter sock. 4-5 hours labor. California trucks rarely see this.
Estimated cost: $1,000-1,600
Owner tips
Flush transmission fluid every 50k miles using OE WS fluid — the A750 transmission is stout but hates neglect
Inspect cooler lines annually in rust states; wire-brush and spray-paint them preventively if surface rust appears
Run full-synthetic 0W-20 oil and change every 5k miles if you tow — oil consumption becomes an issue when rings wear from heat
Check secondary air pump operation each winter before emissions testing to avoid surprise failures
Buy it — the 2021 is the most refined version of a proven platform, and none of these issues are deal-breakers if you budget $1,500/year for maintenance beyond basics.
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.
Fitment notes: Standard top post battery; located under hood
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Every control module on the 2018-2021 Toyota Tundra — where it lives, replacement time, and what it takes to program a replacement. Modules marked dealer / factory tool won't work after a part swap alone — budget for programming.
Multiplex Network Door ECU / Power Window Master Switch (DOOR ECU)0.8 hr R&Rrelearn only +0.2 hr▸ programming details
📍 Driver door, integrated with master switch assembly
🔧 Vehicle procedure (auto up/down relearn)
⚠️ Window auto up/down relearn via manual procedure. No scan tool typically required.
Aftermarket tool coverage varies by software version and vehicle build — treat "aftermarket tool" rows as "usually possible" and verify against your tool maker's coverage list before promising a customer. Spot a wrong location or hour? Tell us — corrections ship fast here.
STEERING:HYDRAULIC POWER ASSIST SYSTEM · 21E103000
2021-12-23
Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain JTEKT power steering gear assembly service parts for 2007-2021 Tundra and 2008-2022 Sequoia, part numbers 44250-0C160, 44250-0C131, 44250-0C170, and 11250-0C121. The power steering gear assembly may have been manufactured incorrectly, which can result in an oil leak.
Consequence: An oil leak may cause a sudden loss of power steering assist, increasing the risk of a crash.
Remedy: Dealers will inspect and replace the power steering gear assembly, free of charge. Owner notification letters were mailed on February 17, 2022. Owners may contact Toyota customer service at 1-800-331-4331. Toyota's number for this recall is 21TH01.
STEERING:HYDRAULIC POWER ASSIST SYSTEM · 21V920000
2021-11-23
Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain 2008-2022 Sequoia and 2007-2021 Tundra vehicles. The power steering gear assembly may have been manufactured incorrectly, which can result in an oil leak.
Consequence: An oil leak may cause a sudden loss of power steering assist, increasing the risk of a crash.
Remedy: Dealers will inspect and replace the power steering gear assembly as necessary, free of charge. Owner notification letters were mailed on January 21, 2022. Owners may contact Toyota customer service at 1-800-331-4331. Toyota's numbers for this recall are 21TB10 and 21TA10.
EXTERIOR LIGHTING:HEADLIGHTS · 21V688000
2021-09-02
Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain 2018-2021 Tundra vehicles. The headlight electrical circuits may power the high and low beams simultaneously, which could overheat the electrical connector.
Consequence: An overheated electrical connector can increase the risk of a fire.
Remedy: Dealers will modify the engine wire harness assembly and replace any damaged bulb, bulb connector, and/or headlight assembly as necessary, free of charge. Owner notification letters were mailed April 25, 2022. Owners may contact Toyota customer service at 1-800-331-4331. Toyota's numbers for this recall are 21TB06 and 21TA06.
Wiper blades
2014-2021 generation (XK50). Pickup trucks do not have rear wipers.
Size-standard part numbers — verify your connector type before buying. Rear blades are model-specific; check the package's vehicle list.
Fuel economy figures are EPA data via fueleconomy.gov (median across matching trims). Performance figures are compiled estimates for the 2021 Toyota Tundra 4.6L V8 and can vary by trim.
🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Lexus & Toyota Mechanic · 20+ years.