Three problems related to differential unit have been reported for the 2004 Toyota Tacoma. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Toyota Tacoma based on all problems reported for the 2004 Tacoma.
The contact owns a 2004 Toyota Tacoma. The contact stated that the transmission rear differential was corroded and leaking transmission fluid while the local mechanic performed routine maintenance. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was 190,000.
Oil changed at Toyota dealer, mechanic discovered rear differential leak. Took the vehicle to private mechanic and discovered the rear differential leak was caused by rust to the body. The 2004 Tacoma had only 27,000 original miles which was brought new. Web search discovered 20 complaints at least on the differential rusting thru. Talking to the mechanic reveal this can be a catastrophic event on a highway with the wheels locking up causing fatalities. Toyota dealers contacted provided no help or did not return phone calls.
My 2004 Toyota Tacoma was recalled in 2012. The recall letter stated that in certain states where road salt is used to manage winter driving conditions, the potential existed for premature rust/corrosion of the frame. I brought the truck in to the dealership where it was then determined that the frame should be replaced. Six months later I noticed that the rear differential housing was leaking. Why didn't the recall cover these components, which are located in the same general area and subject to the same corrosive conditions as the frame, leaf springs, control arms, etc. , all of which were replaced? if the fluid drains from the housing as a result of rust/corrosion, the potential exists for the drivetrain to lock up, especially at higher speeds, resulting in an obviously dangerous situation. No real options exist to address the issue aside from replacing the differential housing, a repair that costs several thousand dollars. My complaint is that Toyota chose not to cover the replacement of all parts necessary in order to insure the safe operation of the vehicle in light of the premature rust/corrosion issue, nor did they raise the issue in any way. I cannot imagine how Toyota could be unaware of this condition.