GarageCalc What the data says
Power train accounts for about 42% of this year's Toyota Sienna complaints. That is a strong concentration, the kind that usually points to a specific known issue rather than general wear.
The 2017 model year contributes 16 complaints (24%). Older vehicles dominate, consistent with age-related wear rather than a new defect.
Complaints are up year over year, 50 to 66 (+32%), against a market that rose about 2%. Year-over-year movement is the most useful signal here: a model's sales are roughly stable from one year to the next, so a sharp rise means the per-vehicle complaint rate genuinely moved, not just that the model is popular.
How to read this
Raw complaint totals track how many Toyota Siennas are on the road as much as they track quality, so a high count on a best-seller is partly a volume story. Complaints are also self-reported: they capture what owners chose to file, not a controlled survey. Use these numbers to know where to look during a pre-purchase inspection and which recalls to check, not as a verdict on their own. Compare any car instantly in the Car Complaint Checker, or read the full 2026 study for the market-wide picture and methodology.
Frequently asked questions
Is the Toyota Sienna reliable?
Complaint counts alone cannot answer that, because they track how many are on the road as much as build quality. What the 2026 data shows: 66 NHTSA complaints so far (rank 145 of 765 models), +32% year over year, with power train the most-cited area. Treat it as a starting point and cross-check recalls and a pre-purchase inspection for the specific vehicle.
What is the most common Toyota Sienna complaint?
Power train: 28 of the 66 complaints filed in 2026 cite it (about 42%). That is a strong concentration, the kind that usually points to a specific known issue rather than general wear.
Which Toyota Sienna model year has the most complaints?
The 2017 model year, with 16 of this year's 66 complaints (about 24%). Older vehicles dominate, consistent with age-related wear rather than a new defect.
Source: NHTSA Office of Defects Investigation complaint database, complaints received 2026-01-01..2026-08-24, compared with 2025-01-01..2025-08-24 (same window). Counted once per complaint ID, vehicles only. Aggregated data is available under CC BY 4.0 with a link to GarageCalc.