How to Replace a Transmission Solenoid – Painless Process!

We hope you love the products we recommend and just so you know that as an Amazon Associate may earn from qualifying purchases.

Understanding how to replace a transmission solenoid can be a useful skill when working on your own car. As the effects of a broken transmission solenoid on a car can be quite drastic.

Neglecting a warning light or code generated by a broken transmission solenoid might result in major issues operating your vehicle. If it is truly broken, then the incorrect gear for the speed and road conditions may be selected by the automatic transmission. This could lead to your transmission overheating and as a result, failing.

how to replace a transmission solenoid - a picture of a modern automatic transmission

What is a transmission control solenoid?

With manual transmission vehicles the clutch works to shift gears yourself. With an automatic transmission system, the change is controlled by a complicated hydraulic system, which uses control solenoids to direct the transmission fluid.

Clutch Packs

Automatic transmissions use clutch assemblies to couple and uncouple the different sets of gears. The flow of the transmission fluids of different clutch assemblies determines the gears will be activated.
Solenoid control

Control solenoids are cylindrical devices that open or close to regulate the flow of fluid through them. When the specific control solenoids are opened, they allow the transmission fluid to flow into the specific clutch assemblies, which changes the gears dedicated to the engine.

Computer controlling

The opening and closing of the control solenoids is controlled by the computer in the solenoid package, the unit on which all the control solenoids are mounted. By directing certain control solenoids to open and another to close, the equipment directs the flow of transmission fluid. This results in control of which clutch assemblies will participate.

A common symptom of a faulty control solenoid is that your transmission may have problems shifting gears. While in motion, your vehicle will slip out of gear. Problems with the solenoid control are often accompanied by you seeing the light control transmission light on your dashboard. Once you have verified that your transmission control solenoid valve is in pain, you need to repair it immediately. Consider replacing the component, rather than attempting to rebuild your entire transmission.

What you need:

  • Replacement solenoid
  • Fluid transmission
  • Transmission filter kit
  • Set of keys and socket
  • flat head screwdriver
  • Oil pan
  • Jack
  • cloth

Procedure on how to replace a transmission solenoid

Drive your vehicle to an auto parts store. Have a technician connect a diagnostic computer code device to your vehicle. Most car stores will do it for free. Use the diagnostic code to identify the electromagnet transmission gone wrong. Your vehicle can use up to six solenoids.

Purchase a replacement solenoid from the auto parts store. Drive your vehicle to a safe place for repairs. A well-ventilated garage may be an appropriate option. Make sure the area you choose has flat terrain and clear enough obstacles.

Park your vehicle and turn off the ignition. Apply wheel blocks to the rear tires to prevent the vehicle from rolling while you replace the solenoid. Lift the front end of the vehicle with a car jack. Place the front axles on jack to keep the vehicle elevated.

Crawl under the hood area of the vehicle. Locate the transmission toward the front of the hood area on the driver’s side of the vehicle. Carefully inspect the transmission. Note that there is a fluid compartment attached to the lower part of the gearbox. Place an oil pan directly under this fluid compartment.

Remove the bolts that secure the fluid compartment to the transmission using a key-and-socket assembly. You can try some plugs before finding the right size plug for the mounting mounting bolts. As you loosen the transmission bolts, the transmission fluid will probably spill out of the fluid reservoir. This is normal and to be expected. Adjust the oil sump needed to catch the leakage transmission fluid. Set each bolt aside when removing it from the transmission.

Lift the fluid container from the transmission with a flat-head screwdriver. Pour the transmission fluid remaining in the oil sump. Set aside the fluid reservoir. Inspect the inside of the transmission.

Locate the electro-magnet box area. Note that each solenoid is color-coded to help you identify the different components. Locate the solenoid you need to replace using the color-coded wires for assistance. Make sure the color-coded wires match the color on the replacement solenoid you purchased. Inspect the solenoid for a mounting bolt. Remove the bolt with a wrench if you find one. Disconnect the wire from the coil by simply pulling away from the electromagnet. Lift the solenoid from the transmission with a flat head screwdriver. Discard the solenoid.

Apply a small amount of transmission fluid to the replacement solenoid. Make sure the O-ring is properly lubricated. Replace the discarded solenoid with the replacement solenoid. Press the solenoid into place until you hear a click. Reconnect the wire to the solenoid. Replace the fixing bolt, if you have already removed one.

  1. I have a 1994 Olds Cutlass Superme S 3.1lt I had an transmission replace in 2015 or 2016 and the shop that done the work says I’ll need a A/T SOLENIOD,but says they don’t repair them,they just install, what can I do?

    • Hey William, thanks for your message. If I were you I’d try another repair shop that does transmissions. If thats no help, hit up an Oldsmobile dealership. If you’re feeling brave, DIY it. But double-check the problem first, alright?

      Hope this helps. Any more questions, just ask.

Leave a reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.