2021 Toyota Highlander Problems

What owners report

Owners of the 2021 Highlander most often describe a whining or grinding noise that dealers trace to an internal transmission problem, with many reporting the transmission had to be replaced. A second cluster of complaints describes fuel filling and distance-to-empty readings that fall short of the stated tank capacity, mostly on the hybrid. Smaller groups report braking hesitation or loss of braking feel, roof rack water leaks, and front bumper detachment referenced to a recall.

1. 1
   Transmission and drivetrain

   Transmission whine and internal failure

   • 216 complaints (41%)
   • median 59,673 mi at 5.4 yrs old (12 state mileage)
   • 2 mention a crash, fire or injury
   • owner-quoted repair $9,000 (median of 42 quotes)
   • filed 2021–2026

   Complaints describe a high-pitched whine, wheeze or grinding sound while accelerating, sometimes at low speeds and sometimes at highway speed. Owners say the noise tends to get louder over time, and that dealers, once the vehicle was inspected, diagnosed internal transmission failure and recommended replacement. Several say the repair was not covered by warranty or recall, and a number mention a Toyota service bulletin on the noise that covers only part of the covered period or a limited range of vehicles. Mostly reported between roughly 50,000 and 90,000 miles, with a few at much lower mileage.

   What to check: Drive at steady speeds and listen for a whine or grind that rises and falls with acceleration, and ask whether any transmission repair or replacement has been recorded. Ask the seller to confirm in writing whether the vehicle falls within the range named in Toyota service bulletin T-SB-0008-21.

   2 excerpts from owner complaints in NHTSA records

   “My Highlander is making a whine noise due to the issue described in T-SB-0008-21. I was never made aware that this was a potential issue. My car is making the whine noise, but Toyota Of Capistrano refuses to cover the cost of fixing it because my car has 86,000 miles. I would have taken the car in sooner had I known of this issue.”

   NHTSA complaint #11682008, filed 2025-08

   “I am reaching out regarding our 2021 Toyota Highlander which currently has $65 K miles and is just out of warranty. Recently we noticed a wining noise during acceleration. We took the vehicle to the dealer who told us that the transmission will need to be REPLACED. $9500 repair. This is a known issue with Toyota and they will not work with us on this. We are stuck! No customer goodwill! Thank you!”

   NHTSA complaint #11718883, filed 2026-02
2. 2
   Fuel system

   Tank will not fill to capacity, low range shown

   Mentioned in 9 of 60 sampled complaints

   Owners report that the tank accepts noticeably less fuel than the stated capacity when the pump shuts off, and that the distance-to-empty display after a fill-up is well below the advertised range. Some describe the fuel gauge staying at full well after driving, or reaching a low reading sooner than expected. Complaints note that dealers confirmed the short fill but told owners there was no repair available. Reported at very low mileage, typically within the first few thousand miles, often on hybrid vehicles.

   1 related service bulletin

   What to check: Fill the tank from near empty at a pump and note how many gallons go in against the specification, then compare the distance-to-empty reading. Ask whether any fuel tank, gauge or sender work has been done.

   2 excerpts from owner complaints in NHTSA records

   “This is not a safety issue per se but one of false advertising. Toyota advertises the range of my hybrid Highlander as 600 miles on 17.1 gal tank at 35 mpg. I do get 35 mpg (which is quite commendable for a vehicle this size) but I cannot fill the fuel tank more than 12-13 gal even when nearly bone-dry empty. In turn I cannot drive any further than 450 miles without filling up. …”

   NHTSA complaint #11406311, filed 2021-04, 600 miles

   “Gas tank only holds 12.5 - 13 gallons with a range of 425-450 at most whereas Toyota claims in their advertising and specs that the tank hold 17.1 gallons and the car has a range of 598 miles. I confirmed with Toyota that this is off specification and they said the tank will only take 14 gallons and the range will decide itself. I use the car for long trips, bought it for the tank size and range and am concerned I am going to run out.”

   NHTSA complaint #11407136, filed 2021-04, 1,903 miles
3. 3
   Brakes

   Braking hesitation or loss of pedal response

   • 72 complaints (14%)
   • median 39,054 mi at 3.3 yrs old (6 state mileage, few)
   • 8 mention a crash, fire or injury
   • filed 2021–2026

   Complaints describe intermittent loss of braking or a lurching forward feel, most often at low speed, downhill, or when coming off a highway on a ramp. Owners report having to press the pedal much harder to slow the vehicle, sometimes after a braking power warning appeared, and one owner reported a wheel speed sensor as the diagnosed cause. Some describe a shutter or stutter through the pedal instead of normal braking. Reported from a few thousand miles up to about 27,000 miles, often at low speed or on a downgrade.

   What to check: Test the brakes at low speed on a slight slope and on a long downhill stretch, paying attention to pedal feel and any hesitation, and ask whether brake-related warning lights or sensor replacement have been recorded.

   2 excerpts from owner complaints in NHTSA records

   “My new 2021 Toyota highlander hybrid having random issues when braking, I noticed most of the time when the car is going downhill, the car will lose braking for a second and I have to depress the brake harder to slow the vehicle. In that second when it loses the brake the car is actually going forward, which can cause unpredictable stopping distance, it can accident if I follow too close. There is no warning light show in the dashboard, the problem is not able to reproduce. It can happen randomly.”

   NHTSA complaint #11424646, filed 2021-07

   “When traveling at slower speeds and applying the brakes on a slight decline, my 2021 Toyota Highlander HYBRID lurches forward with alarming force. On probably 5 separate occasions, this has nearly resulted in me lurching into traffic running perpendicular to me. I have come within 2-3 feet of lunging into oncoming traffic and I am probably the poster child for defensive driving. I had to push the brake petal forcefully to stop. I have not allowed my daughter to drive my car because of this. I first noticed this maybe 2-3 years ago? …”

   NHTSA complaint #11769154, filed 2026-10
4. 4
   Body and structure

   Front bumper cover detaching

   • 24 complaints (5%)
   • median 47,330 mi at 3.8 yrs old (5 state mileage, few)
   • 3 mention a crash, fire or injury
   • filed 2021–2026

   Owners report the front lower bumper cover coming loose or partially separating from the vehicle while driving, in some cases at highway speed, and several tie the symptom to a structure recall on the bumper cover. A number of complaints also note that recall parts were not yet available when they asked for the repair. Reported from roughly 4,000 to 60,000 miles, sometimes after a minor impact or while driving on the highway.

   Recall 23V720000

   What to check: Check the lower front bumper cover for looseness, gaps or prior repairs, and ask whether recall 23V720000 was completed.

   2 excerpts from owner complaints in NHTSA records

   “The contact owns a 2021 Toyota Highlander. The contact received notification of NHTSA Campaign Number: 23V720000 (Structure). The contact stated while driving approximately 35 MPH and exiting a highway with his family, the front bumper assembly detached from the vehicle. The contact stated that the vehicle was steered to the side of the road where duct tape and glue was used to secure the bumper, and the vehicle as taken to the residence. …”

   NHTSA complaint #11684445, filed 2025-09, 60,000 miles

   “The contact owns a 2021 Toyota Highlander. The contact stated that while driving on the highway at 65 MPH, the front bumper became detached. There was no warning light illuminated. The contact pulled over and zip-tied the bumper to the frame of the vehicle. The vehicle was not repaired. The contact referenced NHTSA Campaign Number: 23V720000 (STRUCTURE); as a possible cause for the failure. The manufacturer was notified of the failure. The approximate failure mileage was 47,330.”

   NHTSA complaint #11670880, filed 2025-07, 47,330 miles

Buying note. Have a pre-purchase inspection listen specifically for transmission noise and check the service history for transmission repairs, since that is the most frequently described concern. Confirm that open recalls were completed, verify fuel fill behaviour at a pump, and check the roof area and headliner for water intrusion.

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.