Learn how a transmission is changed

How to Change the Transmission

16 November 2015, 09:33

The very idea of changing the transmission on your car is going to be something that kind of strikes fear into a number of people because it does sound as if it is going to be a difficult task and, at times, that can very well be the case.

However, that is not to say that it is impossible as you will now discover.

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Changing the transmission fluid

First, we shall begin by looking at how you can change the transmission fluid as this is perhaps the easiest part of all.

To start things off you either need to put your car in ramps or jack up the front and remember to put blocks behind the back wheels to stop the car from rolling backwards.

Each car has a transmission pan and if you do not know where to locate it, then check the manual as that will tell you.

As a safety precaution, you should look at disconnecting the negative part of the battery and then look at removing the starter motor if this is required on your particular model.

This will involve removing some bolts and disconnecting the wires, so it does not require any specific mechanical knowledge to get this done.

After this, you should then be left with the transmission pan and at this point it is advisable to have something to catch the oil that is about to come out and also put down old rags on the ground to stop it from staining your driveway if this is where you are doing this repair.

Some vehicles will actually have a plug that allow you to drain this without too much hassle, but if that is not the case, then you will have to remove the bolts for the pan to allow it to drop down and this will then make it easier for you to drain the fluid straight into the pan itself.

At this point, and after everything has drained, it is simply a case of doing the reverse. Finally, you need to top up the fluid when everything has been reattached.

Changing the complete transmission on an automatic

It is important that we point out that you can also completely change the transmission on an automatic car at home even though this is quite a big job to undertake. In order to do this, you must take the following steps:

  • Jack up the car as above.
  • Remove the wiring connectors from the starter, solenoid, switches and sensors.
  • Disconnect the starter and then remove it by taking out the bolts.
  • Drain the fluid as directed above.
  • Disconnect the exhaust pipe at the manifold if it is in the way of the transmission.
  • Disconnect the shift linkage at the transmission.
  • Remove the drive shaft by removing the joints then lower it.
  • Remove the mount from the cross member specifically for the transmission.
  • Lift the transmission up using a jack to remove some of the pressure.
  • Remove the bolts on the transmission member.
  • Remove the actual cross member, but only when the transmission is being supported.
  • Remove the engine plate to gain access to the actual transmission.
  • Remove the torque connector fasteners and replace them with new ones.
  • Remove the engine bolts that connect the transmission.
  • Pull the transmission until it becomes free from the actual engine.
  • After it is removed, you must also take out the torque converter.
  • Line up the new transition correctly by using the guide pins.
  • Reinstall the torque converter.
  • Tighten the mounting bolts for the transmission to the engine.
  • Lift up the transmission and reinstall the cross member.
  • Tighten the cross member whilst checking the recommended torque.
  • Tighten the transmission mount, and check it is now supported.
  • Reconnect the exhaust and the various wires that were disconnected.

As you can see, it is quite a complicated job and that is just for an automatic. A manual car does follow a number of the same steps, but it involves gears and can be more complex and involves more work on your part.

However, it will still be possible to do no matter your make or model as you simply need to consult the relevant manual to make sure that you are doing everything correctly.

Finally, it is worth just reminding you that the specifics may alter slightly depending on your model and if you are unsure about what to do, then do not attempt it as the last thing that you want is to be stuck at the vital moment.

Changing the transmission is something that should only be attempted if you understand the basics of carrying out repairs or things could easily go wrong.

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