O.K. I've done all sorts of searching on this and come up with two forum threads that describe my 4Runner's symptoms exactly: one guy was told that his
transmission pump was going bad, so he traded his 4Runner in to get a different
car; the other guy was told that his transmission needed to be replaced, so he replaced it (at high cost).
I'm hoping somebody else has had this happen and can tell me the resolution without letting a
mechanic have his way with me!
The model: 2002 4Runner SR5
4WD,
automatictransmission
Miles: 218,000
The symptoms: I'm hearing a whine when I put my
transmission in Drive or Reverse. The whine sounds like gears -- kinda like when you hear someone backing up really fast. If my
car is parked, there is no noise until I shift into Drive or Reverse. There is no noise in Park or Neutral. When I start driving, the whine increases in frequency with engine RPM, but the whine stops if I shift into Neutral or let my foot off the accelerator pedal. I notice it in first and second gears. It's too quiet of a noise to hear if I'm going fast enough to be in higher gears.
I've done some close listening, and the whine is definitely not coming from the
engine compartment. I hear it most clearly under the car (where the transmission is!).
The whine seems to be more noticeable when the car has not been driven for several hours.
I've done a complete transmission fluid flush twice over the life of the
vehicle, and the fluid has always looked and smelled good. I use Mobil 1 synthetic ATF. The current ATF level has been checked, and it's good.
Before I shell out a whole mess of dough to replace an entire transmission (since that's what the
mechanics will likely want to do), has anyone experienced this before and resolved it by replacing a transmission pump? Is there even a transmission pump? My Hayne's manual doesn't mention a transmission pump anywhere.
Thanks for the help!!!