1985 Toyota 4Runner Troubleshoot Automatic Transmission

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The automatic transmission in a 1985 Toyota 4Runner transfers the engine's power to the rear wheels, allowing the vehicle to have enough power to operate at both low and high speeds. The use of transmission fluid aids in lubricating the interior of the transmission and acts as a hydraulic fluid in the control of circuits within the transmission assembly. The problem with an automatic transmission is that, because of the interdependence of the different functions and the fluid that services these functions, one small, cheap problem can quickly become several expensive problems.





Troubleshoot Automatic Transmission[edit]

  • Locate the torque converter. It is the spherical metal case that appears to have been flattened on opposite sides. This is the piece that rotates while the engine is running and replaces the clutch system. If the 4Runner is having trouble idling while parked or there is an issue with the transmission shifting between gears smoothly, or if there is a delay between the time the gears shift and the time the transmission responds, the issue is likely related to the torque converter.
  • Locate the shift solenoids. You can use a vehicle manual by Chilton's to find them. The solenoids in the transmission are like mini-electromagnets. When the vehicle is started, the small charge of electricity that goes to the transmission solenoid completes the circuit and allows shifting of the gears automatically. If you notice your gears are hesitating when they shift, or you find that you cannot shift into one of the gears when your engine is on, the problem could be the shift solenoids. Repairing these is not a difficult procedure and is explained in the Chilton's manual.
  • Locate the hydraulic control system. This system uses hydraulic fluid to manage the pressures necessary to operate the valves and throttle to maximize the use of the engine's power output. The vacuum line which is a part of this system helps control the downshift surface on the shift valve. If you notice your RPM is not responding to the automatic shifting without delays or hesitation, you may want to consider a transmission flush or check for leaks of the fluid.
  • Drive your 4Runner after the transmission has been flushed and filled. If you notice the shifting is still not fixed, your problem may not be the transmission at all. If your 4Runner is a four-wheel drive, you will have what is called the transfer case. The transfer case is the part that allows shifting between two-wheel and four-wheel drive. If you have problems shifting from two-wheel to four-wheel, or only certain gears on the vehicle work in either drive, your problem is the transfer case.