the transmission originally was hard to get to go in reverse but ended up losing all forward gears as well.it wouldnt move no matter where the gear selector was. so my initial thought was that the pump shattered the rotor or maybe the slots/lugs for the torque converter possibly broke or stripped. but stupid me did not check line pressure and i did not remove the cooler line to see if i got flow nor did i check the dip stick with and without the truck running. though i did notice a few times when checking the fluid, it was always high, like above the full mark, but to my understanding this shouldnt cause the issue i had unless it was causing it to overheat,

but back to my original diagnosis. i had originally thought it was the rotor in the pump or the slots/lugs but after removing the tranny and taing the pump off and disassembling it. the inside of the pump "looks" good. nothing is broke as far as i can tell.

so my question here is... is there wear inside the pump that can happen to cause it to lose pressure over time? reverse originally was hard, then i noticed 3rd starting to slip and now all of the sudden there are no forward or reverse gears. putting it in any gear is like putting it in neutral. engine does not bog down and i cannot hear any gears engage. now i am thinking that maybe it is the converter instead. removing the pan on the tranny revealed very dark/burnt/nasty tranny fluid that smelled very bad. the last time i crunk it up i did notice that the transmission seemed to have overheated as i could actually smell it that time. so i have the pump out of it and the input drum. i took the reverse clutches and frictions out and some of the clutches are toast. i also pulled the piston out of the drum to inspect the seal and it didnt seem brittle at all and still had elasticity, though it did seem to be kind of stretched or something, it was bigger than the outter diameter of the piston and i could not get it to seat back in there right but the inner seal looked great so i will rebuild it with a budget in mind. so i will go through it and replace the clutches or friction and steels where needed. i am on a budget and need the truck back running.

so to recap:
originally reverse was hard and would slam into gear most of the time.
TC would lock and unlock at weird speeds
then reverse stopped working completely
noticed 3rd started to slip
now no gears at all... no forward, no reverse.

the transmission is sitting in my living room right now tore into a few pieces. i havent dug into the bottom of it yet but plan on it tomorrow. so the main thing i want to know is if my pump could be bad or do i need to worry about the converter? also on the front of the pump, it looks like there is a bushing there that has a split in it? the split looks machined and not a random failure. i will take pic of this and post tomorrow. but if that were where it failed, wouldnt fluid be pouring out of it? also there is a slight ridge or divet on the TC shaft itself. it is smooth for the most part but i can def tell there is either a divet or a ridge there. should i be concerned about that? im digging into the bottom of it tomorrow because i am certain those are worn out after 260,000 miles. the band on it looked great. brand new actually. it makes me wonder if someone didnt recently have it apart and just didnt put something back together right. truck drove like a champ in all forward gears, just had issues in reverse. any help sure would be appreciated. and if you need pics of anything please ask.

p.s. sorry for the lengthy post, just trying to share as much information as i can because it doesnt look liek my pump has failed. but the fluid is toast from overheating i guess. there is also sludge so the filter is probably clogged as well. wouldnt that be funny if it was a clogged filter this whole time hahahahaha. right now i got the input drum assembled with the pump sitting on it to keep the teflon seals the right shape. anyways, like i said, any insight would sure be welcome

 

Pump should be fine after you replace all of the soft parts and bushings in the pump. Inspect the tube in the pump where the teflon seals ride for grooves. The split in the bushing is just the way the bushing was made, it was not the cause of frailer. 260,000 miles is the cause of frailer and it is time of a complete rebuild. With that many miles on it it would best to replace the torque converter also.

The valve body will also need attention; it will most likely have some wear in some of the valve bores. There is more to rebuilding a 4L60E transmission than throwing in some seal and clutches. It will also need almost all if not all of the bushings replaced.

 

i have a good spare torque converter and pump from a one year older 4l60e that had a burnt band. so i have a converter and pump. so i guess i need to get a bushing and seal kit. in the spare tranny it had new (less than 100 miles) clutches and frictions put in the tranny, so i am going to go through that today and see if it is all salvageable. if not then i will need to just get a master overhaul kit. i also have a spare good valve body, but the valve body in the transmission i am working os seemed to be good and actually someone had been in this transission before because the pump had a new seal and it had a blue torque converter and from what i gather the blue one is not stock. but i do not trust that TC or pump now and i know i need new bushings and seals... i just need to go through the rest of this transmission and see what all is good i reckon because i am on a slight budget.

i will post some pics later today of the bushings and seals through out the tranny. i will also post some pics of the valve body. i have a very large table i used to use for tv repairs that will wor perfect for this. but one other question, is it normal for that outter reverse input drump piston seal to be stretched liek that? once i took the pston out, the seal popped off one side and i could not get it to go back in (because it was a larger diameter or stretched.

 

Yes, that is normal most all GM piston seals are like that. It's called a lip seal. Have you watched YouTube videos on rebuilding a 4L60E?

 

yes sir, i have watched a few videos and just got done rebuilding the motor (98 suburban 4x4 5.7) less than 150 miles ago. i have the transmission tore down to the low/rev piston. i will post some pictures shortly and hopefuly i can get away with buying a new complete seal kit, a new bushing kit, and if possible, just new low/rev clutches and stuff. i have the complete input drum from another transmission that the band burned up in, but the clucthes/frictions look brand new. what im trying to do is a budget rebuild man, and as much as i would love to upgrade everything i could, i cannot because of health reason and cash flow and i cannot get out and work and need to get back and forth to doctors appointments. luckly i had my brother and step brother help me remove the tranny and bring it in the house, but i desperately need to get the tranny back in working shape.

although i have never rebuilt a transmission, i have 100% faith in my abilities. if i didnt think i could do it i would have never attempted it. the main reason i asked a question about the lip seal on the piston is because it wasnt hard or cracked after 250.000 - 260,000 miles but it did look stretched somewhat. but i will be replacing that part anyway.

but i will be posting pics of the guts from the current broke transmission and the parts from the donor transmission and hopefully i can get an opinion from the very knowledgable people in this forum. i apologize if i come off as an idiot or misinformed because that is not what i intend. i dont know a whole lot but i also am not going to learn about it just watching videos. so i have to get hands on and ask questions and rtfm and loks at videos etc. but anyways, pics will be posted shortly.

 

I mentioned the videos so you could see how to install the lip seals. When swapping the input drums make sure that the input shafts are the same.

 

they could have used an additive, this could explain why the seal seems "stretched". IMO with 260,000 miles i would say it's been "rebuilt" before. I wouldn't mess around with a used converter, especially one that had "just" a band fail. everyone here will recommend a complete overhaul of the trans and converter. flush the lines and cooler. depending what you find in the pan/teardown may warrant a new cooler. get the thing torn down, take some pics of suspect areas and post them.

 

i wasnt able to get pics yet but i will tomorrow sometime. but there is no material on most of the reverse clutches, they are mostly bare metal lol and the friction plates look like they are kind of blue in a few spots. the low/rev looked great and the input drum i have from my spare tranny has good clutches and stuff... tomorrow i will take a closer look and take pics and post them.

but about that seal, it just seems unreasonably big to me but ii will take some pics tomorrow and post them. im going to replace it anyway. and i am almost certain this thing has been gone through before.

also the fluid in it was black. but the reverse clutches are def toast lol. but anyway i will update the thread tomorrow

 

got the input drum clutch assembly disassembled from both transmissions, got the valve body removed, all check ***** looked ok. seperator plate looked like it was swollen a little. got everything tore apart and mostly organized to go back in. was invited to a friends house to watch the playoffs so i will most liklely not be able to post pics till tomorrow.

 

well i tried to post them directly in the post but the images were way to big and cluttered the thread. so i uploaded them to imgur here:

https://imgur.com/a/U7y1pKF

there is caption on a few of them. the main thing is the blue towel is from current tranny out of the truck i am working on and the orange towel is the spare parts i had. the only thing i have not removed from the transmission is the low-rev piston to check the seals there. but all the seals and bushings are getting replaced anyway. but do you guys think those clutch packs can be reused? most of them look new. the low-rev clutches from both transmissions looked about the same so i will probably just reuse those and replace any lip seals and bushings there as well.

any input is welcome and sorry it took me a couple extra days to get the pics. the playoffs were on the past few days and i just recently had a close fiend pass away from lung cancer so its been a dreary past few days. but anyway thank yall for the information so far. hopefully i can get this thing back together in a reasonable time frame and get it back in the truck.

edit: does anyone have a preference on a seal and/or bushing kit?

also i will have to redneck engineer some kind of press that i can use on the springs to put the snap rings back in place. shouldnt be to much trouble. disasembled it with a flat head screw driver and a seires of fine point picks that have different curves on the end. worked great. also, i have not tore the valve body apart yet to check bores and seals. but that is going to happen this evening and i will post more pics.

the seperator plate was buldged on the bottom side up next to the steel plate that has 3 screws in it. i will take some pics of that as well when i disassemble the valve body

 

took the valve body apart and it looks like the forward accumulator piston bore is etched pretty gnarly. looks like the etching has possibly ate into the seal for the forward accumulatoir piston as well. cant tell if that etching goes down far enough into the seal seat.

does this look like this valve body is junk? how would it have gotten that bad?

 

also, here is a picture of the reverse input drum piston outter seal. it seems to be a bit bigger than the actual piston. i thought they were suppose to fit tight. could this not be the cause of reverse slamming into gear? maybe the seal was wrinkled or something causing fluid to blow by?

 

they probably put one of those additives in the oil to "soften seals". causes the seals to swell and when you remove them they are appear like they've grown. try polishing the foward accumulator bore with green scotchbrite. sonnax makes a sleeve repair kit for the 3/4 accumulator, but not one for the forward accumulator.

 

yes, it got an additive to swell seals.
replace the plastic pistons with aluminum, hand polish the accumulator bores, and they will be OK
Not sure what your budget is on this build, the "orange towel" stuff looks better than the "blue towel" stuff
if budget means you must reuse...you know which to use out of the 2 options

I would not reuse that reverse input drum unless it can be hand polished to remove the surface rusting...and remain flat. Check it with a straight edge.
I'd replace the sunshell with a new piece that has hardened splines

As for tools for spring compressing, I'm sticking with the budget idea here...this will do the low/rev piston in the case, and the reverse input piston

The input drum springs can be compressed using a couple of woodworking speedy clamps and a pair of pine 6" long 2x2 lumber pieces. not elegant but it gets the job done in a pinch.
If you plan on doing a bunch of these transmissions, a foot press, a special tool for the low/rev piston, etc will be worthwhile investments.

 

If you can catch the "scoring" in the forward accumulator bore with your fingernail the VB is junk. If you cant, scotchbrite will take those out. You also want to toss those plastic accumulator pistons and replace with aluminum with a new pin.

Regarding the seal, someone has put additive in the oil which makes those seals swell like that. Either way you arent using that seal again anyway. At least im hoping you werent.....

 

i found this seal kit and bushing kit but i am unsure if they are a good set:

seal kit - https://globaltransmissionparts.com/...ton-lip-seals/
busing kit - https://globaltransmissionparts.com/...t-700r4-4l60e/

do these seem like good quality? what would you guys recommend?

yes what i planned on doing is making up something that looked like a tuning fork (for lack of better wording) but bigger and i may have to make a couple of them for the various springs, but i envisioned something that could press both sides of the springs, and then a long handle that i can put my weight on and hold it while i am putting the snap rings back in. i will post pictures when i make it. it will not be anything extravagant lol but it will get the job done. i used a long thick flat head screw driver to press the springs down to remove the snap rings, wasnt that hard gettign them off, but i know its going to be a trick getting them back on there though lol.

as for the reverse input drum, i have two of them. the one from the transmission i am working on and it is not rusty and is smooth. i may take something and try to scuff it up a little to give the belt a little better grip, but not sure if it is really needed. i will take some pics of the belt and post them later as well.

also, the input drum piston (think it is the 3/4 piston, not the overrun piston. and i have 2. one from the tranny i am working on and another for "parts". both "look good")... one has a lip seal molded to the piston and the other does not. would you guys recommend one over the other? also the input drum from the tranny i am working on didnt have the 3/4 clutch boost spring (i think that is what its called per the pdf i have) and the old parts input drum did. should i reuse these? or leave them out? ive read different posts (like here) that said its ok to leave them out but i am still unsure. i will just use them if nobody recommends leaving them out

 

do NOT scuff it up
"for a better grip"
that's not how that works

as for the 3/4 piston. get a NEW molded piston. I'd strongly recommend you just get a whole set of molded pistons. 3 of them in the input drum.
Use them with the proper springs and be sure to use the #7 apply fingers

things can get tricky mixing and matching parts if you're not familiar with these units.

 

ok so i am going to get these three kits unless someone knows something that is better for around the same price range

master bushing kit- https://globaltransmissionparts.com/...t-700r4-4l60e/
seal kit - https://globaltransmissionparts.com/...ton-lip-seals/
molded piston kit - https://globaltransmissionparts.com/...on-pack-4l60e/

i think with these three kits, and the "good" clutches and friction plates, i will be able to rebuild this thing. the only thing i am worried about is the teflon seals on the input shaft/stator support shaft (i think that is what its called). i also need to check and make sure those ball bearing/ check valves on the input drum shaft are not seized or leaking. but i feel very confident that i will be able to do this. but if anyone could give me an idea if the kits in the links i posted are good? or maybe an alternative? any input sure is welcome. thanks for the help this far

 

Those kits should be okay. I get my kits from Whatever It Takes Transmission Parts.

 

your master seal kit will come with new teflon seals
if you don't have the budget to buy the sizing tools, you can make do without.

put the teflons in HOT water (I have an old POS coffee pot I use. Just make a pot with no grinds, and the boiling water is perfect)
that will soften them up a bit
gently stretch them, one at a time into their grooves, once in their grooves, carefully work a worm clamp to tighten the seal into the groove until the clamp is lightly snug against the shaft. Some guys recommend you use like a cut pop bottle or something between the teflon and clamp if you're worried about "nicking" or cutting the teflon with the clamp.

Repeat for all seals

this is NOT the preferred method, but in a pinch if you are careful you can make it work