Purchased a CERTIFIED used 2021 Highlander XLE from Bernadi Toyota in Framingham MA in September 2023 with 16600 miles.
In May 2025, at 27891 miles and the car 3.8 years old, AC stopped working. Refilled but completely leaked out after just 3 weeks. It was diagnosed as a leak in the rear pipe.
From multiple reddit reports, this seems to be a common occurrence in this generation of Highlanders and is due to two metals at a juncture causing premature corrosion after only 2-4 years, and within the first 36k miles of car ownership.
This is a design flaw. I am a lifelong Toyota owner and lived through the "sludge" controversy/coverup by Toyota on the original Highlander, and this AC issue seems the same in how Toyota responds. The part specifically of all the AC components is on a lengthy backorder, also a clue that this problem is causing a significant demand for the parts.
The estimate to fix is over $2500 because the pipe runs a long length of the car underneath and requires removing many drivetrain components to replace.
Purchased a CERTIFIED used 2021 Highlander XLE from Bernadi Toyota in Framingham MA in September 2023 with 16600 miles.
In May 2025, at 27891 miles and the car 3.8 years old, AC stopped working. Refilled but completely leaked out after just 3 weeks. It was diagnosed as a leak in the rear pipe.
From multiple reddit reports, this seems to be a common occurrence in this generation of Highlanders and is due to two metals at a juncture causing premature corrosion after only 2-4 years, and within the first 36k miles of car ownership.
This is a design flaw. I am a lifelong Toyota owner and lived through the "sludge" controversy/coverup by Toyota on the original Highlander, and this AC issue seems the same in how Toyota responds. The part specifically of all the AC components is on a lengthy backorder, also a clue that this problem is causing a significant demand for the parts.
The estimate to fix is over $2500 because the pipe runs a long length of the car underneath and requires removing many drivetrain components to replace.
- James F., Southborough, MA, US