Three problems related to automatic transmission control module have been reported for the 2004 Toyota Highlander. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Toyota Highlander based on all problems reported for the 2004 Highlander.
2004 Toyota Highlander hesitation in the transmission. Dealer said it was "normal", but I see complaints have been filed and the NHTSA is contemplating a formal investigation. My Highlander hesitates every time I remove my foot from the gas and quickly reapply it. In some conditions, it happens as I'm decelerating and press the gas. Also, periodically, the transmission will jump back and forth between gears as though the vehicle doesn't know which gear to be in.
My 2004 Toyota Highlander v6 (3. 3l with 5-speed transmission) has an intermittent fault where the automatic transmission will abrubtly drop down a gear (or gears) while simultaneously trying to accelerate creating a sensation like it is bucking or porpousing. Usuall stepping off of the accelerator is sufficient to eliminate the bucking sensation. This has occured since I purchased the vehicle new in August 2004.
Transmission hesitation and sudden downshifting create unpredictable and hazardous driving conditions on the streets (not highway).