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Discussion Starter #1
Hi guys, I have a question for you, please: My 4L60e had a cheap, (rounded off tip) lower cooler line that popped out mid-trip on the highway, losing a lot of fluid. I stopped, put the line back in, and added a few quarts of fluid and wanted to limp it home. Got it moving forward again, but it did it again a few miles up the road. The little f&?%er felt solid but kept popping out while driving. Anyway, it took about 3 tries like this, then I used tie-wraps to secure the line in and I finally got it home. It seemed to be slipping a bit but at 4 o'clock in the morning after a 10-hour work shift, who really cares? I have since changed the tip, using a newer, more squared-off tip that will be held in place securely by the C-clip (but I'm thinking of leaving the tie-wraps for good measure). Now, she slips in 2nd at about 2500rpms and will need to go to 4500-5000rpms to shift to 3rd when in 'D'. If I move the lever to '2' she's fine, no slipping at all.
I ordered and installed a Sonnax longer servo pin Part #77787-02K yesterday. I'd estimate (by eye) that the travel was about 1/4" with the first pin and about 1/8" now with the new pin (which is 1/8" longer).
I went for a test drive with it today, when it shifted into second gear, it seemed more 'buttery' and a softer type of a shift than before. It was doing fine until about 2500rpm, then it started slipping again. I continued driving it and after about 5 minutes of faster driving, I noticed the dreaded smoke it the rear view mirror. The one I had seen the first night that the cooler line popped out. The F_*&?%&*G one that is caused by trans fluid on the catalytic converter, burning. Then, lots of revving, more smoke, loss of power...etc. It was leaking all over the road. I limped it home. Looked underneath, the servo cover was missing. And I remembered, just after turning around to limp home, (while swearing) I had heard a metallic-type sound of something falling off but I hadn't seen anything in the rear view mirror. So, I went back and looked around and after 15 minutes I found it in the grass about 20 feet from the road. Finally, something good. Ain't much, but it's something!
I went home and took stock of the situation, I was missing the snap ring that holds the servo cover on but I had an extra 4L60e tranny in the shed, so not an issue, will use that one. I took my time, cleaned everything up, re-installed it. I figured that the snap ring hadn't been put on right the first time, so I really took my time and made sure it was snug all the way around. I took the time to try and estimate the travel distance, and I swear it seems like an 1/8th of an inch to my eye. Went to NAPA, bought MORE transmission fluid. Filled her up to middle 'cold' area on the dip stick. Decided to go for another drive, got to the stop sign at the end of my street...."Cling" --- Stop, look underneath, the F_&%**g snap ring is on the ground and I'm leaking again! Brought it right home, I considered starting smoking again, but instead I wrote this wonderful, frustration-filled post. (while doing breathing exercises)
So far, this transmission has popped the lower cooler line at 2 different occasions, (so I changed the line that seemed to have a rounded tip which wasn't being held in by the clip) and has popped the servo cover and the snap ring off once and popped just the snap ring off the second time. Is there any way that there could be too much pressure inside? Is that a possibility of having too much pressure in there?
What am I left with? Possible that the Pin is too long? If I just re-install the snap ring it is almost a mathematical certainty that it will pop off again....This situation would drive a weaker man to insanity for sure.
Any help you can offer guys would be greatly appreciated.
 

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Some dude on the internet
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Pull your cooler lines and try to blow/flush them out to make sure you don't have a blockage in the cooler circuit.
 

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Discussion Starter #3
Thanks for your reply. Let me give you a bit of the back story and see if we can connect some dots:
The prior own bought it with a working transmission that went bad no long after. So he replaced it with a used unit. Drove it for 4-5 months and it went bad. Had no forward or rearward motion. I bought it like that. I replaced with a used trans and new cooler lines. It was working fine. (Note: I don't drive this vehicle often, so a month can mean 5-6 10 minute drives)
Then one night, the bottom cooler line popped out. I walked to buy more fluid, filled it drove it home. All was fine. I thought it was a badly installed 'C' clip but it felt solid. Then about a month later, same thing happened: lower cooler line popped out. I filled it, trying to drive it home and it happened again about 3 other times that night. The line just wouldn't stay in. So, I kept filling it and limping home. Drove about 15 minutes. She was slipping, it was the first time that happened. And has been ever since but only in 'D', doesn't slip in '2'. So, I replaced the end of the cooler line which looked cheap and rounded off, then I tie wrapped the tip in, it'll never come out again, Promise! So, to try and fix the slipping in 'D' when she goes into second gear at around 2500rppm, I ordered a longer servo pin from Sonnax. First time out, still slipping at 2500rpm, then not long after the servo cover flew out and pissed everywhere. So, maybe I lost the snap ring early on. Then, I reinstall everything better including the snap ring and it came out again.
Could there be an issue in the primary or secondary trans radiator that could cause a build up of pressure that would make these damn things come loose? I was led to believe that my snap ring install probably wasn't right and the servo cover wasn't fastened right. This thing sure blows a lot of transmissions, no? I have a feeling that the pressure buildup is an issue but I'm not an expert so please tell me what you think.
Thanks for your help.
 

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Some dude on the internet
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Yes, I read all of that explanation in your original post. Any time a trans is replaced, you should completely and thoroughly flush your lines (or replace) and coolers. If you shelled 2 trannies, there could be a bunch of shit in the coolers causing blockage (pressure issues), and you're just going to be back to square one. I know you replaced your lines, but did you flush your coolers?
 

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Some dude on the internet
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Follow your trans lines up to the front of your vehicle, they will go into your radiator oil cooler fittings, and then into your auxiliary cooler if you have one (will be in front of your condenser, behind your grille).

The way I do it is use compressed air and brake cleaner. Disconnect both lines at your transmission, point one end at a drain bucket, and blow air through the other (lines only, DO NOT blow air into your actual trans). If you can't get fluid/air out the other end, you have a blockage.
 

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Discussion Starter #8
Hi again,
today I cleaned out the snap ring grove to 'like new' condition. While doing so, I noticed that the servo cover popping out yesterday cracked the housing on both sides of the opening used to get a screw driver under the snap ring. There are 2, one is at the 6 o'clock position: That one! Who cares? I carried on anyway! I checked the fluid level, getting it nice and hot, added 1/2 quart above full, so about 1/4" over on the dip stick.
Then I took it for a test drive, having the shorter, original pin in there...Result: it seemed to slip a bit less but still slips at about 2500rpm. No slip in '2' gear. And if I gun it, it doesn't slip either.
Then I swapped the longer Sonnax pin back in. While getting under the pin, I took out a chunk of that cracked housing lip, say about 3/4". But I don't care, I mean at this point, right? There still is lots of lip holding the snap ring in place and nothing is leaking, so --- Carry on. Did the test drive and it still slips, probably just as much as with the shorter pin. At 2500rpm. Again no slip in '2' gear, or when I gun it! The only difference is it sounds like something is making a whining/dragging type sound and I'm wondering if the band is dragging. Not sure, what do you think? Possible? Also, I flushed both coolers for good measure, just to make sure they weren't clogged with anything. So, that's done!
So, what do you think? What should my next move be?
 
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