4l80e rebuild on a suburban

kawan

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On the case body where I place the 8 check balls, I noticed wear on 2 of the holes as shown. Don't see much info on this when I did a search except for one person who said its normal on high mileage. Should I try smooth it out ? ( kind of a nuisance since I should have done it when the case was empty or before I even had it cleaned) or leave it ?
 

kawan

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1) Also, just for my piece of mind ... should the oiling holes of the shaft be lined up to the oiling holes of the sun gear? I did not think so, but would like to know what you think. 2) I was at National Transmission Parts and they had the split silence ring for $10. My 4l80e on tear-down did not have one. I can put one on but would it affect my rear or front end play? I don't want to redo the end play measurements again. Thanks
 
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On the Checkball "Bathtubs" in the case......Break off any aluminum flashing with a pair of needle nose pliers. Or just leave it alone. The oiling holes DO NOT need to be indexed. The Silencer Ring will NOT affect rear unit end-play.
 

kawan

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Thanks! If you think I should put the silencer ring I will do it. Else I will skip it since I have it all buttoned up.
 
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Originally Posted By: kawan
Thanks! If you think I should put the silencer ring I will do it. Else I will skip it since I have it all buttoned up.
It's not absolutely needed. It does help the Center Support & Reaction Carrier Bushings last longer, The more power you make....The more the silencer is needed. GM did make the decision to eliminate it for '95 production.
 

kawan

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I have a question on the Torque Convertor. I read in many places and it makes sense that I should not re-use it. Transtar and Natpro sell rebuilt ones but I am not sure if their re-builders use cheap Chinese parts inside. They actually have them in stock so I give mine and walk away with another. How do I tell if mine is stock GM? But my transmission did not at all look bad , no metal shavings etc in the fluid when I took it apart to rebuild. I can ask around for shops that have machines that can flush=h out Torque converters but I see that that process involves drilling ... can get metal shavings in etc Should I just get a rebuilt one for about $150 to $200 at transtar/natpro? or re-use mine?
 
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Factory GM converters are not painted & will have a I.D. sticker on one or both sides. 4L80E converters come in Single Stator & Dual Stator versions.....The ID tag will tell them which one. Every Rebuilder for the most part tries to keep costs down as much as possible. They usually just cut the converter open & inspect the internals, Clean it....Shim the End-play & weld it back together. You would be surprised how many "rebuilds" had NO parts changed at all!!! There are exceptions....But you get what you pay for! For example, I have a $950 Circle-D converter in my Camaro. You may want to ask around in your area to see who has the best reputation! I use a local shop for my standard builds called "Performance Torque Converters of Texas"......I have great luck with their rebuilds BUT I do not trust them to build a Custom high end/high stall converter because they flat lack experience in setting custom stall speeds.
 

kawan

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Here is a picture of my tc Has a stickers on both sides showing 8683 670 etched on the sides were the markings k118k3
 
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is any body still following these posts? i seem to have gotten myself into a real pickle, i have a 4l80e out of a 1994 k2500 2wd i want to put it into my 1985 chevy conversion van which used to be a 6.2 diesel. i didnt want to mess with a computer so i followed Chris Kokonis's "How to easily convert the 4l80e to full manual. it worked for a while but it didnt feel like i was always starting off in first, and it was not slamming the shifts like i was warned. then the TCC stop working, i wondered if i had installed one of the forward or driect clutch drum middle seals in up side down. so i researched that and decided that dual feeding would be cool i follwed instructions from all the you tube videos i could find, i believe i pulug al the correct passeges, i reassembled installed and with in 48 hours i had smoked the forward and direct drum fibers and steels burnt to a crispy, after an autopsy and many hours of research and many repurchased new parts i reassembled and attempted to install the tranny and torque converter and the verter was up against the flex plate, i learned that i had installed the incorrect O Ring on the input shat and i think that is what idid previously to burn it up. i pulled it down and replace the o ring with correct slimmer one, and have the tranny reinstalled plumbed up topped off 12v running to it and now there is no reverse, i have read that it can be slow to engage. i put all of the check balls back in, upgraded to Sonnax check balls.

at my wits end geeze

putting together a line pressure tester as i write but as usual one fitting short of completion
 
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See if you have adequate line pressure......Then go drive it & confirm 3rd gear/Direct operation.

What did you find to cause the Forwards & Directs to burn down?

How are you controlling Line Pressure? Vacuum Modulator Kit......Or.......Are you really going to run the unit at max line pressure & expect it to live on the street?

Guessing you "Dual Fed" the Direct Clutch?
 
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yes i did Dual Feed the Direct. i am wondering if i have the correct reverse band with the correct drum, i read about smooth and coarse drum as to thats why some bands have the grooves in the fiber and others do not, I am fairly confident that i burned up the forward clutches because i had installed the Wrong Oring on the input shaft i put to thick of a oring on and the converter never seated into the pump. I am going to follow the advice i have read on these posts, and from learning about the CK performance instructions and leave out the #5,6 check balls because i am going to do a accumulator delete, and also remove reverse check ball for faster reverse engagement, which means i think i will remove the trans mission again. i just recieved my trans pressure checker so i will be able to check the pressure, i think i will check it for the experience and see what it is doing pressure wise in there.

i did not go the boost kit, and i ground down the reverse boost land on the valve, cross drilled for bleed off, i think i did the standard procedures, enlarged drain back for converter,

i have a TH400 that i had built years ago with a shift kit ran it behind my 520 cadillac and it would snap gears when shifting, so when i read that these mods on the 4l80 would cause some snappy shifts i was looking forward to it, BUT i did not notice any difference in shfting force, i drove my first attempt rebuild 4l80 with full manual mods sereval thousand miles with no majot issues that i was aware of., but i did leave the center seal on the dierect and forward drum with the dual feed so i took out the tranny to remove the seals and see some improvement, i created these problems this time because i wasnt satisfied with the shifts and 1st didnt feel like it was biting {possible i had been starting out in second} and thus the can of learning worms has been released upon myself, i almost feel like i asked my mom a question, i really didnt want to know that much about it it, but it is time to learn
 
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'97 & up "Center Lube" 4L80E's have the smooth Band & Reaction Carrier, Though you can use early "grooved" Band on a late Reaction Carrier......Don't use a Late Band on a Early Carrier.

I like to use OE TH400 Grooved Bands on ALL my TH400/4L80E builds.....But they are getting tough to find.
 
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'97 & up "Center Lube" 4L80E's have the smooth Band & Reaction Carrier, Though you can use early "grooved" Band on a late Reaction Carrier......Don't use a Late Band on a Early Carrier.

I like to use OE TH400 Grooved Bands on ALL my TH400/4L80E builds.....But they are getting tough to find.


Awesome advice i am going to take advantge of this weekends nice weather and get back onthe tranny and see whats up, im having a thought that when i "cleaned up the carrier i may have cleaned to much off and the reverse bande is now too large to engage, quite the learning experience! i shall post again when i have some new results
 
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They get damaged from the manual shift shaft getting banged around. If the nail doesn't just fall out.....See if you can get it turning (Lineman Pliers work best), Pull straight on the nail while turning it counter clockwise.

They can be quite bent & not turn, I use a small dent puller/slide hammer with a 10-1.50mm nut on the end of manual shift shaft to straighten the nail out. You may have to use the lineman pliers to keep the nail in the same orientation.

There are tools to change the shift shaft seal without removing the shift shaft!
 
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They get damaged from the manual shift shaft getting banged around. If the nail doesn't just fall out.....See if you can get it turning (Lineman Pliers work best), Pull straight on the nail while turning it counter clockwise.

They can be quite bent & not turn, I use a small dent puller/slide hammer with a 10-1.50mm nut on the end of manual shift shaft to straighten the nail out. You may have to use the lineman pliers to keep the nail in the same orientation.

There are tools to change the shift shaft seal without removing the shift shaft!
Accumulator valve spring and shift feed hole questions.
I have a 4L80E with a stock torque converter 1800-2000 stall that I have installed a Superior Transmissions Shift kit.
There is a Heavy Duty option to replace the accumulator valve spring in the valve body with a lighter spring that would have the effect of firming up all three forward shifts. I don't think it effects reverse.
I have blocked off both 3rd and 4th accumulators so the only shift that would be affected should be 1-2.
I have a wave and 4 high energy frictions in the intermediate clutch with .048 clearance.
1.)
Should I use the lighter spring to firm up 2nd? What impact would it have as compared to increasing the feed hole from the stock .070 to say .085?
2.)
What feed hole sizes would be appropriate for firm shifts given a 1994 C2500 7.4 genVI big block with a [email protected] comp cams bigger injectors good exhaust etc. tuned for about 500 ft-lbs flywheel. i was thinking of .085 (w/light spring) 2nd, .093(blocked accumulator)3rd, .085(blocked accumulator)4th.
Thanks in advance
Oh yeah....What is a "backout shift"? is that a down shift? I have seen this term referenced regarding the valve body accumulator valve/spring
 
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Forgot to mention I did the dual feed the directs internal mods the cam is a roller and stock feed hole sizes:

2nd .070 with active accumulator
3rd .076 with active accumulator
4th .055 with active accumulator
R .055
 
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