4l80e direct clutch feeplay

[blackbeard_lives]

assembling my 4l80e rebuild. my favorite nick's transmissions rebuild video shows putting the direct clutch drum on the center support and plugging a hole or two with your fingers and applying compress air to the reverse or direct feed hole on the center support to push the piston on the direct clutch and use a dial gauge to measure the throw distance the clutch pack closes up when the piston pushes upward. but when i put air in the clutch isn't compressed against the spring, air just leaks out, not enough sealed in to hold air pressure and push the piston against the spring pack and close the clutch plates together. i put 3 sealing rings on the center support, leaving one out for the dual feed, since it didn't work i put a seal on the dual feed 2nd from top ring and clamped it with a worm gear clamp overnight to compress the nylon. gonna work on it again friday and get back to this post late that night. any advice appreciated.

also, my 02 4l80e from a gmc 1500 HD sierra i'm pretty sure didn't have a cone shaped cushion plate underneath the clutch stack, and my rebuild didn't come with one, but i'm learning my year transmission was supposed to have one? only 91-96 didn't have cushion plate???

thanks for y'all's time.

 

[strutaeng]

assembling my 4l80e rebuild. my favorite nick's transmissions rebuild video shows putting the direct clutch drum on the center support and plugging a hole or two with your fingers and applying compress air to the reverse or direct feed hole on the center support to push the piston on the direct clutch and use a dial gauge to measure the throw distance the clutch pack closes up when the piston pushes upward. but when i put air in the clutch isn't compressed against the spring, air just leaks out, not enough sealed in to hold air pressure and push the piston against the spring pack and close the clutch plates together. i put 3 sealing rings on the center support, leaving one out for the dual feed, since it didn't work i put a seal on the dual feed 2nd from top ring and clamped it with a worm gear clamp overnight to compress the nylon. gonna work on it again friday and get back to this post late that night. any advice appreciated.

also, my 02 4l80e from a gmc 1500 HD sierra i'm pretty sure didn't have a cone shaped cushion plate underneath the clutch stack, and my rebuild didn't come with one, but i'm learning my year transmission was supposed to have one? only 91-96 didn't have cushion plate???

thanks for y'all's time.

Did you replace the direct piston? Maybe the seal got folded back when you installed it?

Was that transmission overhauled at some point before? I've only rebuilt two of these units (both 95 models) and what either one of them lacked, was the cushion plate for the intermediate clutch. There should be a direct cushion plate, however for most any application. You can just purchase that part at like WIT or online.

Maybe @NickTransmissions can offer more advice.

Welcome to the forum BTW!

 

[NickTransmissions]

assembling my 4l80e rebuild. my favorite nick's transmissions rebuild video shows putting the direct clutch drum on the center support and plugging a hole or two with your fingers and applying compress air to the reverse or direct feed hole on the center support to push the piston on the direct clutch and use a dial gauge to measure the throw distance the clutch pack closes up when the piston pushes upward. but when i put air in the clutch isn't compressed against the spring, air just leaks out, not enough sealed in to hold air pressure and push the piston against the spring pack and close the clutch plates together. i put 3 sealing rings on the center support, leaving one out for the dual feed, since it didn't work i put a seal on the dual feed 2nd from top ring and clamped it with a worm gear clamp overnight to compress the nylon. gonna work on it again friday and get back to this post late that night. any advice appreciated.

also, my 02 4l80e from a gmc 1500 HD sierra i'm pretty sure didn't have a cone shaped cushion plate underneath the clutch stack, and my rebuild didn't come with one, but i'm learning my year transmission was supposed to have one? only 91-96 didn't have cushion plate???

thanks for y'all's time.

Hi Blackbeard,

Pull the piston out and check the lip sealing surfaces on your piston (im assuming you have a new bonded piston - if not, obtain one)...Also make sure the sealing surface in the drum isn't compromised in any way or the inner diameter of the direct drum doesn't have sealing ring groove wear.

For dual feed, there should be no center seal in the drum but the piston should be sealing as well as moving when air is introduced. You will need to plug the high reverse passage in your ctr support when doing the air check otherwise air will go into the direct feed and come right out of the high reverse feed, piston will not move.

How much PSI were you using for your air?

I like to at least have 75 psi when air checking, esp when dual feeding something since more air charge is needed, generally speaking.

 

[blackbeard_lives]

thanks for the welcome to the forumn. yeah i need to check the inner diameter of the direct drum to look for wear. I realized on the bus ride home that maybe i forgot to press a bushing into the direct drum causing the air leak. I think i'm gonna take the top clutch steel ring that has some light wear to the machine shop so that my 6 clutch stacks with .030" clearance can gain some clearance to get into the .040-.055 spec. My kit came with 5 .080" and 5 .090" steels, using one .090 steel and 5 .080 steels I get .030 clearance, if i had one more .080 steel I could get to .040 clearance. When i screwdriver the clutch stack topper steel against the dial caliper it moves .030" before stopping on the snapring.

I'm wondering why i have so many clutches for the direct in my kit, am i gonna need 5 clutches for somewhere else in the transmission and i only have 4 now that i am using a 6th in the direct?

i'll try to take some pictures of the new piston and seals on that piston and see if there are any cuts from installing with a feeler gauge lol. And the direct drum, see if we can find any reason the piston won't close the clutch stack.

thanks much for the help

 

[NickTransmissions]

thanks for the welcome to the forumn. yeah i need to check the inner diameter of the direct drum to look for wear. I realized on the bus ride home that maybe i forgot to press a bushing into the direct drum causing the air leak. I think i'm gonna take the top clutch steel ring that has some light wear to the machine shop so that my 6 clutch stacks with .030" clearance can gain some clearance to get into the .040-.055 spec. My kit came with 5 .080" and 5 .090" steels, using one .090 steel and 5 .080 steels I get .030 clearance, if i had one more .080 steel I could get to .040 clearance. When i screwdriver the clutch stack topper steel against the dial caliper it moves .030" before stopping on the snapring.

I'm wondering why i have so many clutches for the direct in my kit, am i gonna need 5 clutches for somewhere else in the transmission and i only have 4 now that i am using a 6th in the direct?

i'll try to take some pictures of the new piston and seals on that piston and see if there are any cuts from installing with a feeler gauge lol. And the direct drum, see if we can find any reason the piston won't close the clutch stack.

thanks much for the help

The dir drum doesnt take a bushing.

How exactly are you measuring your clearance in those two drums?

List the steps you're taking...want to make sure you're doing it correctly.

 

[blackbeard_lives]

are the clutches that go in the direct the same clutches as go somewhere else? why does my kit have more of these clutches than I need? if i put 6 in the direct am i stealing a clutch i need for somewhere else? i wanna put an order into global transmission parts tonight but am unsure what to buy other than a 6th .080 thin steel.

the machine shops won't help me resurface my top ring, gonna go to the glass shop and get a scrap piece of glass to glue sandpaper too so i can refinish this thing myself.

TH400 4L80E Forward Clutch HE Friction Plate (0.80'' / 2.03mm)

Free Shipping on All Transmission Parts & Rebuild Kits Orders Over $35. Multiple warehouse locations in Las Vegas and the East Coast gets you transmission parts fast.

globaltransmissionparts.com

does this part replace the borg warner high energy clutch i stole from the kit and put in the direct 6th clutch or did my kit come with way too many clutches?

thanks for your time, appreciate it tonnes

edit i think this clutch would be a better replacement

TH400 4L80E Forward Direct Clutch High Energy Friction Plate

Free Shipping on All Transmission Parts & Rebuild Kits Orders Over $35. Multiple warehouse locations in Las Vegas and the East Coast gets you transmission parts fast.

globaltransmissionparts.com

 

[NickTransmissions]

are the clutches that go in the direct the same clutches as go somewhere else? why does my kit have more of these clutches than I need? if i put 6 in the direct am i stealing a clutch i need for somewhere else? i wanna put an order into global transmission parts tonight but am unsure what to buy other than a 6th .080 thin steel.

the machine shops won't help me resurface my top ring, gonna go to the glass shop and get a scrap piece of glass to glue sandpaper too so i can refinish this thing myself.

TH400 4L80E Forward Clutch HE Friction Plate (0.80'' / 2.03mm)

Free Shipping on All Transmission Parts & Rebuild Kits Orders Over $35. Multiple warehouse locations in Las Vegas and the East Coast gets you transmission parts fast.

globaltransmissionparts.com

does this part replace the borg warner high energy clutch i stole from the kit and put in the direct 6th clutch or did my kit come with way too many clutches?

thanks for your time, appreciate it tonnes

edit i think this clutch would be a better replacement

TH400 4L80E Forward Direct Clutch High Energy Friction Plate

Free Shipping on All Transmission Parts & Rebuild Kits Orders Over $35. Multiple warehouse locations in Las Vegas and the East Coast gets you transmission parts fast.

globaltransmissionparts.com

Hopefully you havent done anything like sand your pressure plate.

Please answer my question - list and describe how you are measuring your clurch clearance. I suspect you're not doing it correctly but want to confirm based on what you tell me.

I wont answer any other questions unless you respond to the above; its critically Important to follow the correct procedure.

Also, Please quote my posts or mention me - i dont get alerts if you just reply in the thread without quoting or mentioning me like this: @NickTransmissions

I just happen to see you had made another post in here just now.

 

[blackbeard_lives]

Hopefully you havent done anything like sand your pressure plate.

Please answer my question - list and describe how you are measuring your clurch clearance. I suspect you're not doing it correctly but want to confirm based on what you tell me.

I wont answer any other questions unless you respond to the above; its critically Important to follow the correct procedure.

Also, Please quote my posts or mention me - i dont get alerts if you just reply in the thread without quoting or mentioning me like this: @NickTransmissions

I just happen to see you had made another post in here just now.

setting a digital dial caliper on the edge of the direct basket, lowering the finger out the bottom to the pressure plate, setting the caliper to zero, using a pick to raise the pressure plate to the snapring stop, and repeating 8 or 9 times and looking for the consistent average. shopping ebay for a dial indicator. my method isn't what the pros do but i got steady hands, i was leonardo da-vinci in a past life ha. I haven't sanded the pressure plate yet. I have .028" clearance, using my technique. replacing a clutch plate .090 with a .079 could put me at .039" and maybe break in would move it to the .040" minimum spec but that's unverifiable and kinda hoping my clutch stack performs the same as the ones youve disassembled and measured.

i couldn't manage to get the snap ring off the spring holding the direct piston in place. when i get the snap ring off tomorrow i'll take pictures of the direct piston and look for some thin plastic or something to aide reinstall if the piston is fine. gonna try the compressed air test with no spring and a full clutch stack to stop before blowout, but look for compressed air to make the piston move. after the test attempt i will disassemble to look for piston faults, it is new, i don't think i cut the seal on install but i could have. last test i had fingers plugging the 3rd oil feed hole and the hole i drilled in the drum for an extra relief to prevent wrongful apply of third clutch stack. about 75 psi of air going into the reverse hole on the right, nothing plugging the center support bolt hole, but air was coming out between the center support and the direct drum, 3 split black style seals installed on the center support, i don't have the nylon compression tool but i ordered a spare kit of those seals so i may chuck the split black ones that don't stick out as far as the white nylon seals.

I am really impressed by your newer 4l80 video and the time you spend on forums helping us get our wheels rolling. I got a friend flying out at the end of the month so a working truck by july could be very fantastic. but if it's still a project in july we will have fun assembling it together.

thanks again for your time nick, from jacob

 

[NickTransmissions]

setting a digital dial caliper on the edge of the direct basket, lowering the finger out the bottom to the pressure plate, setting the caliper to zero, using a pick to raise the pressure plate to the snap ring stop, and repeating 8 or 9 times and looking for the consistent average.

Watch this video (re-watch if you've already watched) - skip to 1:20:00 and see how I measure my direct clutch clearance....If your process is not identical in every way to mine then re-do the clearance check mirroring the steps I show here:

 

[blackbeard_lives]

Watch this video (re-watch if you've already watched) - skip to 1:20:00 and see how I measure my direct clutch clearance....If your process is not identical in every way to mine then re-do the clearance check mirroring the steps I show here:

been rewatching yours and dr. shocks and others 4l80 videos every day for months now, very helpful stuff


edit: now i feel dumb, cut the piston seal on install, buying a new piston and .079 steel and clutch disc so i don't run short of parts.