Forums - Reply to Topic
Thread: 4L60E Build Up Thread From FLT Reply to Thread
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:

Register Now

In order to be able to post messages on the Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

  Additional Options
Miscellaneous Options

  Topic Review (Newest First)
03-05-2009 03:23 PM
IT_SS i never knew there was so much involved in rebuilding a tranny, i need to have my done personally....
01-04-2009 04:58 PM
Vince @ FLT Next we install the clutch pack for the reverse input clutch. The first plate to be installed will be cushion plate. It will be installed cone side up. Here are the photo's.

Next is to install the first steel. This will be followed up with by clutch and then repeated until all four steels and four clutches have been installed. Here are the photo's.

The next step is to install the pressure plate and the snap ring. Here are the photo's.

In the next set of photo's I will show how I preset my end play by using the pump stator. Also I will cover the machine process of our pumps along with the assembly of the pump. Enjoy the photo's and stay tuned. More to come. Vince
01-04-2009 04:55 PM
Vince @ FLT
The reverse input drum

I left off with the input drum fully assembled and installed in the transmission. The next step will be to get the reverse input drum ready to be installed in the trans. Here is where we left off.

Here is a photo of the reverse input drum.

This is a piece that is used for more than one purpose. Not only do the clutches inside the drum get applied when the trans shift selector is placed in reverse, but the outside of the drum is used to apply the 2-4 band. With that being said it also is used for 2nd and 4th gears. Here is the photo of a new drum that we use in almost every unit that we build. Also here are the internal components and the band that this drum uses.

The only time I will reuse this drum is when it is totally perfect which is very rare for a used 4l60e. Most companies will reuse these even though they have signs of wear. The band surface warps. The lugs where the sun shell splines together wears. Also the area where the apply cushion plate rides wears out. This will cause damage to the input drum from it being allowed to rub due to more travel side to side in the reverse input drum. Also I have seen where it can cause the reverse input piston to bind on the apply. Causing a delayed engagement in reverse or a strange double bump apply. A used drum when in good condition should have the bushings replaced and also have the band surface resurfaced. I have seen many attempts of the outside to be resurface by hand sanding or sanding discs on a die grinder. I prefer to use a lathe to resurface the drum. I will use sandpaper by hand to resurface it while the drum spins on the lathe. Then finish it off by polishing it with scotch bright. When I'm done it looks very close to the one in the picture above. It will then be checked to verify that it is flat and smooth.

Once the drum is clean and ready to be assembled the first step is to get the seals installed. Here are a couple photo's.

Next it is a good practise to lube the seals with assembly lube or use a seal lubricate stick to do so. I like to use the seal lubricate stick but it is just builder preference. Here is a photo of the piston lubed and ready to be installed.

The next it is time to install the reverse input piston. Here are a few photo's.

I like to use a long feeler gauge to help install the piston. This will help to not damage the seals.

Once it is all the way down it is time to install the spring cage and it's snap ring. Here are a few photo's of how it's done.

Next we install the reverse input clutches.
01-04-2009 04:48 PM
Vince @ FLT Here is another picture of the 3-4 clutch assembly ready to be installed in the drum.

The first plate to be installed is the new 3-4 apply plate. Here are a couple photo's of it being installed.

Next we will install the clutches and steels. Once again it will start with a clutch followed by a steel until all 8 frictions are installed along with 7 steels. Here are the photo's.

Now it is time to install the new pressure plate. These plates come in different thicknesses to adjust the 3-4 clutch clearance. You can also tighten this pack up by the use of thicker frictions. Some guy's will use different thickness steel plates or snap rings but I like to do it with frictions and pressure plates. Here is a photo of the pressure plate being installed along with the snap ring.

The drum is now complete. It is a good practice to check the clutch clearances with the use of feeler gauges after air checking the drum. Air checking the drum will seat the clutch pack and the snap ring in the drum. This will give us the most accurate measurement. Also while air checking the drum it will verify if there are any leaks in the drum and the seals of it. Here is a picture of the drum fully assembled ready to be installed in the trans. One picture of the trans without the drum and one with it in the trans.

In the next segment I will be assembling the reverse input drum and it's assemblies. Stay tuned and feel free to ask any technical questions. Enjoy the thread. Vince
01-04-2009 04:45 PM
Vince @ FLT As I left off in the above post it is time to get the forward clutch assembly ready to be installed. Note that 5 frictions, 5 steels, a new pressure plate installed for adjusting clutch clearance, and the snap ring that keeps everything in place here in this photo.

Here is a line up of this assembly.

The first step is to install the first forward steel. This is much like any other clutch pack as it will alternate from a steel to a clutch and end up with the pressure plate. Here is a picture with the steel in the drum.

Then a clutch will be installed and the the process will be repeated until all 5 steel and clutch plates are installed. Here are the photo's.

Then the forward clutch pressure plate will be installed. We do use different thickness plates from GM to achieve the proper FLT clutch clearance for this clutch. Here are the photo's of it being installed and also the snap ring that is used to retain these parts.

The next step will be to install the 3-4 clutch pack assembly. At FLT we use an 8 pack clutch set up with Coleen steels. All of these pieces are replaced with new parts in every new unit that we assemble. This includes both the apply plate, pressure plate, frictions and the steels. Here are a couple photo's of the parts used and also the line up of the parts.

Next we will install the 3-4 clutch assembly.
01-04-2009 04:43 PM
Vince @ FLT
Time for the clutches and sprag install

In this next portion of the thread we will be installing the clutches in the input drum. We left off with the internal pistons being installed along with the modified spring cages. Here is a picture as to where I left off.

The first things to do now are to install the input drum to sprag bearing and put a little assembly lube on the seal for the lube circuit connecting the input drum to the output shaft. Here are some photo's.

Now it is time to install the overrun clutches, steels and also the backing plate which also acts as the apply plate for the forward clutch. The line up of these parts will start with a steel, clutch, steel, clutch and then the backing plate. Here is the line up of these parts outside of the drum.

This first picture has the first overrun steel installed.

Then we will install the first clutch and repeat the process.

And then finish up with the backing plate.

At this point the wave plate can be installed for the forward clutch. This plate is designed the way it is to absorb some of the shock of the apply of the forward clutch. Here are a couple photo's of it.

And one with it installed in the drum.

Next we will get our input sprag assembly together. It will have have the sun gear for the front planet with the bushing already installed. The sprag race surfaces carefully inspected to be in good condition. The sun gear will also be inspected for pitting or abnormal wear. If any of these pieces do not meet our criteria they are replaced. A new Borg Warner sprag is also installed at this point and time. Here are a few photo's of the assembly as it goes together.

Also once all the pieces are installed and the snap ring that keeps it together is in place, I will lube the bushings.

Now the sprag assembly is complete and can be installed in the drum.

The next step will be to get the forward clutch assembly ready and installed.
01-04-2009 04:10 PM
Vince @ FLT The next step is to get the forward piston, forward piston housing, the modified 3-4 clutch spring cage and the 3-4 apply ring ready to be installed. Here are a few pictures of how I stack them up.

This next set of photo's are of the install of these parts.

Next we will install the modified overrun piston and the spring cage.

With the new modified spring cages transgo supplies us with a larger washer that will be used to compress the spring cage. It is needed so that the overrun cage does not get bent when it is compressed and the snap ring is installed.

I will remove the washer supplied from transgo and the drum is now ready for the overrun, 3-4, and forward clutch assemblies to be installed.

In the next segment I will show the clutch assmeblies being installed. Enjoy the photo's and feel free to ask a tech question. Vince
01-04-2009 04:07 PM
Vince @ FLT In my last post we left off at the input drum being sleeved and the input shaft being pressed back in the drum. These next photo's will be of the internal pistons, retainers, modified spring cages, seals and 3-4 clutch apply ring being installed.

This first picture is of the sleeved drum ready for the assembly of the internal components.

The first steps that we take are to install the internal seals of the drum. Here are the ones that I am referring to. The top one is the new 3-4 steel bonded apply piston. Bottom left is a oring that seals the forward clutch housing and also the new 3-4 clutch piston. Bottom right seal is a seal used for lube oil from the input shaft to the output shaft. Here is a photo of the seals.

Here is a photo of the lube seal for the two shafts. It gets installed in the input drum here.

The next seal that I will install is the green oring. Here is where it will be installed.

The new 3-4 clutch apply piston is the next to be installed. Here are a couple of photo's.

Next we will install a modified seal installer. This installer has been bored to accommodate for the steel sleeve that we have installed.

Here is a line up of the components that will be assembled into the input drum.

The next step that I will do is to get our spring cages ready to be installed. These are the cages that we will modify with the use of springs from transgo. The idea with these springs is that they are heavier and also will greatly reduce any centrifugal apply at high rpms with the 3-4 clutch/overrun clutch. Here are the factory cages.

As you can see in this photo the 3-4 return spring cage is held together with little hooks. They will need to be bent out of the way in order to get it apart and remove the factory springs. Here are a few photo's.

Here is a photo of the overrun/forward return spring cage. I will first remove the bottom of the cage using a small screw driver. Then I will use a pair of wire cutters to remove the springs from the top portion of the cage.

Here is a photo of both cages fully apart with the new springs that we are going to install.

Here are photos of the 3-4 cage and it's new springs. Note the first picture the springs are tapered and will snap in place.

To be continued............
01-04-2009 04:03 PM
Vince @ FLT
The input shaft being installed with the Teflon seals

Here we are going to make sure to line up the splines for the input drum an the shaft. Notice the double wide spline that centers things.

Next we will use a light amount of lock tight on the area where the feed holes are on both the shaft and the drum. Also put a good bead on the splines of the shaft itself.

Next it will be time to put the shaft in the hole of the drum. Making sure to line it up properly and then tap it down with a rubber mallet or plastic dead blow hammer. It should not go in very far and we are just making sure that there is proper resistance at this point and also that it is seated properly/aligned.

Now we will head to the press. Once again using a large socket to support the drum to avoid any chance of cracking or stressing it. Here are a few photo's of the setup.

The shaft is now installed and here are a few photo's of the finished product of the sleeved drum.

Next we will install the input shaft Teflon seals. These are done by the use of a seal installer and a resizer. Here are some photo's of them being installed and then sized.

I will next do the assembly of the clutches, steels, pistons, spring cages and the input sprag. Stay tuned and enjoy the photo's. Vince
01-04-2009 03:58 PM
Vince @ FLT
The beginning of the front half being installed.

I am starting the build of the front half of the transmission. Refer to my last post to see where we left off. This next set of photo's is going to show how we build our input drums in our level 4 and 5 units. This will be a segment on how each and every sleeved drum gets done here at FLT. This drum in my opinion is a very good upgrade and makes this trans much stronger. The idea behind the sleeved drum is that it will keep the aluminum drum from expanding and not allowing the input shaft to float in the drum. We have seen this many times in the past and also in cores that we tear down. Most shops never remove these shafts and for us it is mandatory. This is a picture of where we left off.

Here are some photo's of the drum completely disassembled. All surfaces have been inspected, cleaned and critical surfaces have been polished ready for assembly.

We always pay close attention to the surfaces where the input shaft will be pressed in and also that all splined areas are acceptable. This first picture is where the shaft will be pressed in.

Here is a photo of the area where the reverse input clutches will ride. Also note the area where the feed holes will be aligned and the quality of the surface.

Now we take a look at the inside of the drum. We are looking for bad ridges where the steels will ride. Slight wear marks are ok and in most cases the drum is reusable. Here is a photo of the inside of the drum.

Here is the pieces that will be installed next. They include the drum, sleeve and the input shaft.

Now we are ready to install the sleeve in our drum. The first thing to do is to apply a thin layer of lock tight to the drum and the sleeve. Then line up the lube hole slot for the overrun clutch. Here are a couple photo's.

Now that we have the sleeve in place it is time to put it in the press. In most cases the arbor press will work for the install of the sleeve. If not we have larger press that works as well. I will make sure to support the drum when pressing on the sleeve. This will assure us that it will not get cracked or stressed during the process. Here is a photo of the setup on the press.

After getting things lined up, I use an old bearing race to press the new sleeve on the drum.

Then we press the sleeve down. They go on with quite a bit of resistance and that is what we are after. Here are a couple photo's of the sleeve being pressed on. One from the top.

Another that I got a little creative with. Thought it was a cool picture.

The drum is now sleeved. Here is the photo.

Next we will install the shaft.
This thread has more than 10 replies. Click here to review the whole thread.

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

For the best viewing experience please update your browser to Google Chrome