Valve Body Page 1
Link to other parts of the project
Project ZF 5HP19 transmission
Link to all videos for the transmission project
Project 5HP19 transmission: Videos
Valve Body Videos
Overview
Changing of gears inside the transmission is done by engaging or releasing a series of clutches that connect the different gears inside the engine. The clutches are controlled by the valve body. The valve body is basically a hydraulic unit. Oil pressure for the unit is provided by the oil pump.
The valve body is at the bottom of the transmission. When you open the pan, it's the big lumpy metal thing that the filter is attached to. It comprises of a number of separate valve bodies that are bolted together to form the one unit. Also it has the solenoids that control oil flow, as well as the electrical connections for these.
Why would you want to pull this out and work on it? From the reading I've done, this is the first part of the transmission that will deteriorate. It won't wear like you think, but there are plastic and rubber components, as well as lots of springs that work like an orchestra to give you the beautiful gear transitions that you love. When these start to deteriorate, the gear changes will become rough, and the transmission just won't work like it used to. There is probably no significant wear on the actual transmission parts at this time, but with more time, this will happen because the valve body isn't doing its job properly. Fixing the valve body is probably going to be very good for the longevity of the remainder of the transmission.
There are very few parts that are normally replaced inside the valve body, just a few dampers and some O rings. The reason things deteriorate is because the body gets glugged up with old contaminated oil, which stops the valves operating correctly. Parts of the valve body get good oil flow, so changing your oil regularly will clear this out. There are parts however that don't get good flow, and the only way to clear this all out after years of use is to pull the valve body apart and clean it all out.
Before we start, this isn't for the faint hearted. If you are someone who is a bit disorganized, and you tend to lose things, this may not be the job for you. There are about 150 individual components in here. There are lots of things that look the same but aren't, and if things get mixed up, it just won't work properly. Also, it is essential that when assembled, it is perfectly clean. Any foreign bodies in here are just going to jam things, and stop it working. The way I cleaned and organized things (as I described in the intro post) seemed to work well. I would suggest something like this.
The good news is that it is definitely a DIY that can be done, and it can be done with the transmission still in the car.
First, put it on jacks like you are going to do a transmission oil change. Drop the pan and remove the filter.
Prior to removing the body, there are some electrical items that need removing.
1. Unbolt the output speed sensor and leave it hanging.
2. Disconnect the plug for the input speed sensor. The input speed sensor (turbine speed sensor) is bolted underneath, and will remain in the transmission when the valve body is removed.
3. Push in the big electrical plug from the outside.
4. The plugs on the solenoids stay in place, and the whole harness will come out with the valve body.
Now remove the valve body. Below is a diagram of the bolts that you will see. You will notice the bolt heads are either large or small. They both take a T27 torx, but the bolt head and actual bolt sizes are different. The bolts with the large head are those that are holding the valve body to the transmission case. These are the ones you need to remove. It's pretty easy to see, but if you are having trouble, an easy way is to get a socket (I found a 10mm worked well) and try and fit it over the heads of the bolts. The small ones fit, the large ones didn't.
Update: Later valve bodies have different size bolts. The valve body in my car at home has T40 torx bolts that connect it to the transmission case (14 in total). The remainder are all T27, which hold the valve body together. See photo below. Some of the brown bolts are 6mm, some are 5mm. It is pretty obvious where they go when you put it all back together.
The best way to remove the valve body, is to lower the 14 T40 bolts about 8mm (black circle bolts on the photo above), and allow all the remaining oil to drain. You will get about another 2 litres of fluid when you initially separate the valve body from the casing as the clutches and about ½ of the torque converter drain. This is best done when the transmission is warm so it comes out more easily. It will take a long time otherwise. Once all the oil has drained you can then remove the valve body from the transmission. I would suggest making some sort of jig that connects to a transmission jack or trolley jack that will hold the valve body weight to make it easier to removed and install.
When you remove the valve body, my suggestion is to make a stand for it. This is what I made. It worked well. The problem with the valve body is that it is heavy, slippery, an awkward shape, and there are a lot of machined faces that mount directly to the transmission body without gaskets and are used for oil flow. Damage to these would be bad.
Here are some photos that show the different components of the body, and how to disconnect things.
With the electrical harness disconnected, it's now time to dismantle the body. Remove the 6 solenoids at the back now, but don't remove the single one until you remove that body. The solenoids that are the same colour are interchangeable, as they are the same part number. You can take some photos if you like, but they will only fit in the place for that type of solenoid.
Remove the individual bodies and dismantle all the components and clean, sort etc. The springs and pistons are held in by a couple of means. Here are a couple of photos that show how this all fits.
IMPORTANT: When you are pulling this stuff apart, you must keep track of where every individual component goes. My suggestion is this. Have the valve body diagram open and check that it looks the same as you remove the components. Some of it won't because the document is for a different transmission model. If it is different, take a photo of where it came from and the orientation of the components for assembly.
Link to other parts of the project
Project ZF 5HP19 transmission
Link to all videos for the transmission project
Project 5HP19 transmission: Videos
Valve Body Videos
Overview
Changing of gears inside the transmission is done by engaging or releasing a series of clutches that connect the different gears inside the engine. The clutches are controlled by the valve body. The valve body is basically a hydraulic unit. Oil pressure for the unit is provided by the oil pump.
The valve body is at the bottom of the transmission. When you open the pan, it's the big lumpy metal thing that the filter is attached to. It comprises of a number of separate valve bodies that are bolted together to form the one unit. Also it has the solenoids that control oil flow, as well as the electrical connections for these.
Why would you want to pull this out and work on it? From the reading I've done, this is the first part of the transmission that will deteriorate. It won't wear like you think, but there are plastic and rubber components, as well as lots of springs that work like an orchestra to give you the beautiful gear transitions that you love. When these start to deteriorate, the gear changes will become rough, and the transmission just won't work like it used to. There is probably no significant wear on the actual transmission parts at this time, but with more time, this will happen because the valve body isn't doing its job properly. Fixing the valve body is probably going to be very good for the longevity of the remainder of the transmission.
There are very few parts that are normally replaced inside the valve body, just a few dampers and some O rings. The reason things deteriorate is because the body gets glugged up with old contaminated oil, which stops the valves operating correctly. Parts of the valve body get good oil flow, so changing your oil regularly will clear this out. There are parts however that don't get good flow, and the only way to clear this all out after years of use is to pull the valve body apart and clean it all out.
Before we start, this isn't for the faint hearted. If you are someone who is a bit disorganized, and you tend to lose things, this may not be the job for you. There are about 150 individual components in here. There are lots of things that look the same but aren't, and if things get mixed up, it just won't work properly. Also, it is essential that when assembled, it is perfectly clean. Any foreign bodies in here are just going to jam things, and stop it working. The way I cleaned and organized things (as I described in the intro post) seemed to work well. I would suggest something like this.
The good news is that it is definitely a DIY that can be done, and it can be done with the transmission still in the car.
First, put it on jacks like you are going to do a transmission oil change. Drop the pan and remove the filter.
Prior to removing the body, there are some electrical items that need removing.
1. Unbolt the output speed sensor and leave it hanging.
2. Disconnect the plug for the input speed sensor. The input speed sensor (turbine speed sensor) is bolted underneath, and will remain in the transmission when the valve body is removed.
3. Push in the big electrical plug from the outside.
4. The plugs on the solenoids stay in place, and the whole harness will come out with the valve body.
Now remove the valve body. Below is a diagram of the bolts that you will see. You will notice the bolt heads are either large or small. They both take a T27 torx, but the bolt head and actual bolt sizes are different. The bolts with the large head are those that are holding the valve body to the transmission case. These are the ones you need to remove. It's pretty easy to see, but if you are having trouble, an easy way is to get a socket (I found a 10mm worked well) and try and fit it over the heads of the bolts. The small ones fit, the large ones didn't.
Update: Later valve bodies have different size bolts. The valve body in my car at home has T40 torx bolts that connect it to the transmission case (14 in total). The remainder are all T27, which hold the valve body together. See photo below. Some of the brown bolts are 6mm, some are 5mm. It is pretty obvious where they go when you put it all back together.
The best way to remove the valve body, is to lower the 14 T40 bolts about 8mm (black circle bolts on the photo above), and allow all the remaining oil to drain. You will get about another 2 litres of fluid when you initially separate the valve body from the casing as the clutches and about ½ of the torque converter drain. This is best done when the transmission is warm so it comes out more easily. It will take a long time otherwise. Once all the oil has drained you can then remove the valve body from the transmission. I would suggest making some sort of jig that connects to a transmission jack or trolley jack that will hold the valve body weight to make it easier to removed and install.
When you remove the valve body, my suggestion is to make a stand for it. This is what I made. It worked well. The problem with the valve body is that it is heavy, slippery, an awkward shape, and there are a lot of machined faces that mount directly to the transmission body without gaskets and are used for oil flow. Damage to these would be bad.
Here are some photos that show the different components of the body, and how to disconnect things.
With the electrical harness disconnected, it's now time to dismantle the body. Remove the 6 solenoids at the back now, but don't remove the single one until you remove that body. The solenoids that are the same colour are interchangeable, as they are the same part number. You can take some photos if you like, but they will only fit in the place for that type of solenoid.
Remove the individual bodies and dismantle all the components and clean, sort etc. The springs and pistons are held in by a couple of means. Here are a couple of photos that show how this all fits.
IMPORTANT: When you are pulling this stuff apart, you must keep track of where every individual component goes. My suggestion is this. Have the valve body diagram open and check that it looks the same as you remove the components. Some of it won't because the document is for a different transmission model. If it is different, take a photo of where it came from and the orientation of the components for assembly.