93 4l60E (probably electrical) Problem with shifting.

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ODaily

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Still not working.

Pulled and replaced the Hot Garbage wiring harness.
Filled with an appropriate amount of ATF.
Did a complete front end rebuild, cause why not?

Went for a test drive.
I have 1st, and if I wrap it up and let off the throttle, 3rd. Same as before. No changes.

I did notice something that I hadn't before. If I'm in 3rd, and I manually shift into 2nd, I get neutral, or total slippage at least. Manually shifting into 1st works normally as witnessed by my local PD, when I pulled off a rapid decel and tire bark right in front of him. Nice.

Truck is back in the shop, and I'm headed for shower / bed.
 

1997

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nice job sticking with it. If you're like me, the little neighbours kids learnt some new words ......

short story, might help with your morale .... my 95 had a code 82,no check engine light, just sets, google it, bet the only results are mine, anyways, gave up, figured i'm no expert, posted here, nothing, so took to "the best trans shop around here", a week later, "ya, we don't know what's wrong, gave me info on a place that supposedly specialized in old stuff",
and charged me $350.

that motived me to fix the damn thing , it's not rocket science, if you have the manuals and it's OEM, who ever writes them does a get job, thou they over simplify it, haha.

1st and 3rd is weird, is that symtom in the 4L60E_80E_CODE_BOOK.pdf?

and yes it did "fix it" .. new ECU.
 
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ODaily

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I ran out of new words a coupla months ago. If this keeps up, I'm gonna hafta learn to curse in German or something.

As far as I can see the codebook only works if you have a code as a starting point, so no codes.

I was looking at the image you posted back on the first page of this thread about shift solenoids, and I noticed the 2-4 both use the band / I don't have 2-4. Which got me to thinking, I changed the 2nd servo during one of my many many trans pulls. Basically I took out the Sonnax billet servo, and went back to the 'vette servo.

What if I F-ed it up? Anything from misassembled to cut oring. If the servo wasn't applying or was stuck or something, would that give me the symptoms that I have? It sounds like a long shot, but nothing has been normal or easy about this so far.

If that's not it, I'll just have to keep finding things to check until I nail it down.
 

tayto

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I would definitely check/replace the servo seals. perhaps you assembled something wrong.
 

ODaily

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Thing is, I drove it after installing the 'vette servo. Not far, it was still leaking then, but far enough.

I see four options.
1. Some weird failure in the servos.
2. The band broke. Probably where the metal is spot welded near the ends.
3. The case broke, where the band anchors.
4. I somehow disconnected the band when I had the front pump out.

I'm thinking that no matter what it is, the trans is coming out. again. dammit.
 

ODaily

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4 hours sleep last night, so forgive if i miss details.

It's out.
Couldn't find any damage. That's good, cause expensive parts aren't trashed. That's bad cause I still don't have a smoking gun.

Did have one oddity. The front drum came out real easy. In fact it came with the front pump when I pulled it. Normally the band kinda hangs on to it. But that also means I couldn't look at the band in an undisturbed condition.

Possible theory... I may have dislodged the band from it's anchor pin when I previously pulled the front pump ( during the great snipe / leak hunt). It felt that way when I opened it, but because the front drum came out in a rush, kinda hard to say.

I really hate that i might / maybe / kinda have an answer. Everything stays apart till I can get new gasket and oring anyways. I think about it some more when I'm not wasted tired.

Side note. Went from running truck to transmission on the tailgate in pieces at about 1.5 hours. Starting to feel like I'm training for some kinda speed run. That's the 7th pull.
 

tayto

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what is your servo travel? easy to check while unit is out. remove servo seals, install servo cover&snap ring and then push on cover until it bottoms, check with dial indicator
 

ODaily

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I think it was .085 with the sonnax servo and shaft. Shaft length is near identical with the GM shaft I put back in. Did that in truck last time, and didn't feel like messing with it.

Will have to get gaskets and re-assemble before I can recheck.
 
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