I own a 4 cyl 2004 Toyota Highlander with 40000 miles. Although the owner’s manual makes no specific mileage recommendation about when to change the transmission fluid, I wanted to have it changed. The local shop wanted about $198.00 to merely drain and replace the fluid. (I believe they just syphon it out and replace it). I bought an inexpensive syphon and plan to do it myself. Is there anything I should be aware of regarding this job? Thanks.
Using this method only removes 25%-30% of the total transmission fluid held in the tranny. The rest is held in the torque converter. So unless there’s a drain plug on the torque converter, this is like draining 2 quarts of engine oil out and adding two quarts of oil and calling that an oil change.
If you want to get the full benefits of a tranny fluid change, find a shop that uses a transmission fluid exchange machine. This exchanges 100% of the tranny fluid. But when having this done, make sure they drop the pan to inspect for debris in the pan and that the filter is either changed or cleaned. You can probably get this done for less than $198.00 you were quoted for just the pan drop and add.