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Who here works on their own Auto transmission?

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Rolling around youtube looking at transmission stuff for an issue I am having and came across this guy.

Apparently he knows wtf he's doing. Impressive.

 
They're really not that hard to work on. I've rebuilt a Turbo 350, Turbo 400, c4, c6, Torqueflight 727, 4l80E and some god-forsaken Mercedes transmission so far... Put a hole in your bench or make a little stand with a hole in it, and stack up your parts as you pull them out. Clean the case real well, and blow it out with a blow nozzle. Don't use rags to wipe it out because they will leave lint in there. Then after the case is clean take the top part off your stack, clean that component up, blow off with air, replace any wear items (bushings, clutches, lip seals, thrust washers, sprag rollers/springs, sealing rings, etc) and then put it back in the bottom of the case. Move onto the next component. Some clutch packs will require a spring compressor tool to get them apart and back together. When putting lip seals in a transmission rebuild lube (or vaseline) and a feeler gauge are your friend in order to get the lip started into it's bore. After you assemble a component with a lip seal, if you can, air check it with a rubber tipped blow nozzle to make sure that it works and doesn't leak.
 
billybob_81067 said:
They're really not that hard to work on. I've rebuilt a Turbo 350, Turbo 400, c4, c6, Torqueflight 727, 4l80E and some god-forsaken Mercedes transmission so far... Put a hole in your bench or make a little stand with a hole in it, and stack up your parts as you pull them out. Clean the case real well, and blow it out with a blow nozzle. Don't use rags to wipe it out because they will leave lint in there. Then after the case is clean take the top part off your stack, clean that component up, blow off with air, replace any wear items (bushings, clutches, lip seals, thrust washers, sprag rollers/springs, sealing rings, etc) and then put it back in the bottom of the case. Move onto the next component. Some clutch packs will require a spring compressor tool to get them apart and back together. When putting lip seals in a transmission rebuild lube (or vaseline) and a feeler gauge are your friend in order to get the lip started into it's bore. After you assemble a component with a lip seal, if you can, air check it with a rubber tipped blow nozzle to make sure that it works and doesn't leak.
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How bad of a job was the C6? That's the one I am looking at doing. Basic tools and a press for the bearings?
 
Impressive? Sierra College had a blind dude that worked there or was on staff or on retainer. Blind dude built and diagnosed transmissions and was excellent at it.

fuck anybody doing it with eyes. :shaking: Nerds.


edit: personally, i've scrapped out several auto trans :flipoff2:
 
flecker said:
How bad of a job was the C6? That's the one I am looking at doing. Basic tools and a press for the bearings?
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It's been a long time since I did that one, but yeah, basic tools. inch pound torque wrench for the valve body, telescoping magnet to pull check balls out of the valve body. O ring picks for the seals and o-rings and whatnot. You might have to rig up a tool to compress springs out of some all-thread and short sections of pipe and washers or something like that. Just keep track of all the small parts as you pull them out and make sure you get them back in. On the valve bodies I would usually just clean them in solvent and NOT pull out each individual spool valve. Just work them back and forth in solvent to make sure they can move like they are supposed to. If you have one sticking then you can pull that particular one out and figure out why.

Basically a C6 is about as simple of an automatic transmission as you can get. Make sure the governor weights and spool valve move freely and the vacuum modulator works with a hand held vacuum pump. If you're cheap and there isn't anything wrong with your torque convertor you can drill and tap them for a 1/8" pipe plug and drain all the fluid out and re-use it. If you don't drain the fluid out then you're putting that contaminated old fluid right back into your freshly rebuilt transmission.
 
Oh and get yourself a book on it. They will show end play tolerances (you'll need a dial indicator to check those), and will also have a chart in them that shows what clutch packs are applied for each gear. That way if you have a particular gear that is giving you problems you can look at that chart and see what is specific to that particular gear that could be wrong and focus your attention to that area when rebuilding.
 
I tried doing a Turbo 350 a couple years ago. Fawk snap rings.
 
I did a TH350 that turned out great. No problems at all with it. I just bought the book and went to town on it. I didn't have to buy any special tools for that one.
 
I've watched that guys videos before. He certainly knows his stuff!
 
If you're just doing a stock rebuild the hardest part is getting good service literature so that you know the shit you're putting back together isn't fucked up and fits correctly. If you're modifying one then it's just like engines, you need to understand how everything goes together.

Domestic rwd/4wd transmissions are cake because there's so much good service literature out there.
 
Just don’t try to set everything at the minimum. A buddy and I started rebuilding them 20 years ago. They wanted 3k for a 47re rebuild. I told him that’s crazy. Even if we pulled it out of the truck three times it was still worth trying. Well we pulled the first one out three times. But just like every thing else, the more you do the easier it gets. Get a factory manual and keep it open and handy. He did a 4l60 the other day. Worked out great. And instead of drilling a hole in his table to build the last one, he had a wooden bar stool he punched a hole in and built it on that.
 
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I just play parts yard transmission roulette.

Why do you need to drill a hole in table/stand?
 
they're way easy
just get a refrigerator or radiator box and lay out all the bits in the order they came out
got an old motor manual for all the domestic stuff that's pretty great, covers up to e4ods
 
Ebs said:
I just play parts yard transmission roulette.

Why do you need to drill a hole in table/stand?
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Easier to work on them in a vertical orientation.
 
Sawdust + grease will greatly improve functionality & quiet any upshifts/downshifts-
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Ebs said:
I just play parts yard transmission roulette.

Why do you need to drill a hole in table/stand?
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When you pull the stack of stuff out of the transmission you put your input shaft through the hole in the table and stack everything on top of it like a fucked up christmas tree. Then you need something shorter to stand your transmission case on end with a hole in it for the tailshaft to stick through so you can put stuff back. Gravity helps immensely in getting your planetaries and clutch packs all lined back up and slipped into place.
 
TrailTamer said:
ATSG manual, ftw
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Yup, great manuals in my experience for damned sure.


We have a couple adapters for engine stands to hang autos from the bell housing. Makes life real easy being able to stand it up or lay it flat for valve body work.

C6 is an odd duck in that it stacks gears instead of changing them if I remember right. Band adjustment is critical on them too. Been many, many moons since I've touched one but that's what I can remember anyway.
 
Good literature is important. My 4l80 was rebuilt and had multiple years of parts in it which is fine as long as everything add up to the right tolerances and you order the correct wear parts.
Be careful when doing modifications as off road modifications will differ from drag strip modifications. Many of the internet videos and tutorials are for street and strip not off-road.
Make sure all the upgrade parts work together.
When measuring stack up or end play tolerances with a dial indicator, make sure you are fully moving the assemblies all the way in both directions. You might have to pry to fully seat everything to get an accurate reading. Some of the readings are compounded so what you measure might be two parts moving and you need to take the reading when 1st stage end and you feel 2nd stage start. Point is make sure you are getting valid measurements.
Don't rush it, it takes forever when learning and double checking everything and reordering parts that were not correct or messed up.
 
HYDRODYNAMIC said:
Don't rush it, it takes forever when learning and double checking everything and reordering parts that were not correct or messed up.
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And don't "lets do epic burnouts, just to finish off the slipping transmission, what's there to lose?!?"

seal kit, and maybe few frictions and steels will quickly turn into many new part required to repair/rebuild the trans. lol
 
What can really suck about an auto trans is you cut or tear one lip seal way down in the bottom and the whole pile wont work. I just rebuilt my 4L60 in my shop truck. It would move but barely. So I yanked it out and took it to my transmission guy and asked him to pull it all the way down and double check my work. He said the entire stack was good and the last thing he checked was the apply servo on the outside of the case. I had cut one of the lip seals. :homer:

But....about a month later I grenaded it with a liberal application of throttle. I'm not building my 80, just took to him to start. :laughing:
 
[486 said:
;n285065]they're way easy
just get a refrigerator or radiator box and lay out all the bits in the order they came out
got an old motor manual for all the domestic stuff that's pretty great, covers up to e4ods
Click to expand...

thats what i did, big ass piece of cardboard and everything laid out in the order it came out
 
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