Dear Doctor: I have a Toyota RAV4 AWD with 100,000 miles. I followed the owner’s manual recommendation and never changed the transmission fluid. The fluid is now a grayish brown color. Should I change the fluid at this point? Mechanics have said if I change it now I may experience transmission problems. Presently the vehicle is shifting well and I have no problems with the automatic, which has always maintained the proper fluid level. Chris
Dear Chris: I would recommend changing the fluid. This is done on most Toyota vehicle with a simple drain plug in the transmission pan. When the plug is removed about 3.4 quarts will drain out. I suggest you continue to do a fluid drain once a month for the next three months. This will slowly change the fluid over time without any concern. Make sure you use only factory Toyota transmission fluid.