12-16-2023, 10:01 AM | #26 |
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Re: Shifting at high RPM
Is that modulator getting vacuum?
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12-16-2023, 10:10 AM | #27 |
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Re: Shifting at high RPM
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12-18-2023, 09:53 AM | #28 | |
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Re: ****ing at high RPM
Quote:
The gear is in good condition,
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12-18-2023, 09:58 AM | #29 | |
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Re: ****ing at high RPM
Quote:
I’m thinking of buying new governor and vacuum modulator, however I’m not sure what brand to buy. Any recommendations? 🤔 Note I live 5000 miles from USA, so I must make sure I buy the correct part. Thanks 🫡👋🏻
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12-18-2023, 02:37 PM | #30 |
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Re: Shifting at high RPM
If it moves, there is no reason to waste money on another one. Cleaning it out was good. If anything buy a weight kit and an extra gear for it if you anticipate issues in the future. There had to have been a gasket on there, if there wasn't there would nave been a huge leak while driving. I'd pickup a couple of gaskets also. As to the shifting?? I don't know, if the valve was sticking somewhat and is now loose. I'd put the governor back in and try driving it and see what happens. If it still won't shift, there may be a sticking valve in the valve body under the vacuum modulator. See if you can pull it out with a magnet. What condition is the oil in....nice and clean?
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12-18-2023, 03:10 PM | #31 | |
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Re: Shifting at high RPM
Quote:
There was no leak at all prior to removing it, no gasket just silicon. Oil is new and clean. I’ll put back, see if ok, Regarding your suggestion of fishing the valve, how do I pull it out?
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12-18-2023, 06:25 PM | #32 |
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Re: Shifting at high RPM
One possible thing that might cause a shifting issue is if the o-ring on the filter tube is damaged, worn, or missing.
Amazon link that shows the o-ring as part of a kit: https://www.amazon.com/ACDelco-TF231...2935891&sr=8-3 I noticed that some kits don't show the o-ring. It is needed or you won't get good fluid pickup and will have symptoms similar to low fluid levels. Including bad shifting. #7 on the diagram shows where it goes. Another thing some folks miss is removing the old one if it sticks in the opening when you pull out the tube #14. I would finish your check of the modulator and related stuff before pulling the pan. Pulling the pan probably means replacing the pan gasket + 4~7 quarts of ATF. No point in doing that until you know the problem isn't in the modulator you already have off. |
12-18-2023, 08:45 PM | #33 |
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Re: Shifting at high RPM
the problem may stem from the silicone used to seal the gov cover. An automatic transmission is no place to use silicone. A small chunk of it will get in the governor and case it to stick.
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12-19-2023, 02:28 AM | #34 |
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Re: Shifting at high RPM
I totally agree. However, This truck never had any issues with trans since I owned (2015), it parked for 3 months due to paint work. Otherwise all ok.
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12-19-2023, 10:11 AM | #35 | |
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Re: Shifting at high RPM
Quote:
This is not the issue, otherwise shifting problems will happen after the oil change.
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12-19-2023, 12:48 PM | #36 |
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Re: Shifting at high RPM
This is a huge issue ^^^^. You may have already dis-lodged the culprit, but A small piece could have lodged itself anywhere in the valve body. Did you try to pull the valve out behind the vac modulator? It's about a 1/2'' in diameter and about 2-3'' long. Magnet will be useful
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12-19-2023, 12:52 PM | #37 |
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Re: Shifting at high RPM
[Quote]...... Another thing some folks miss is removing the old one if it sticks in the opening when you pull out the tube #14.
If the tube butts up against it ..yes. But you can actually double up the o rings if you have the deep pan to help retain the extension tube. |
12-23-2023, 03:59 PM | #38 |
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Re: Shifting at high RPM
Greetings to all,
Sorry for late response. I was sick (corona or flu) not sure. Again, trans oil is new and clean, drove it less than 200km since last oil & filter change, all GM products. No silicone inside the governor housing. When replacing the old filter, I made sure the old o-ring is removed, the new o-ring was lubricated with trans oil, then it was fitted in the filter neck, then it was placed inside the housing. Truck drivers normally. Update 12/23/2023 8:30pm my time. I cleaned the governor tested the valve it works fine, made a gasket from gasket paper, put it back, added new oil to replace the spilled oil. Drove the truck, no change, it will not shift. I’ll try to fish the valve body behind the vacuum modulator, and see. Otherwise I’m out of ideas.
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12-23-2023, 08:19 PM | #39 | |
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Re: Shifting at high RPM
Quote:
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12-23-2023, 08:56 PM | #40 |
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Re: Shifting at high RPM
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12-24-2023, 05:43 AM | #41 |
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Re: Shifting at high RPM
I’ll try to pull it out, is it easy to put it back🤔?
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12-24-2023, 05:46 AM | #42 | |
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Re: Shifting at high RPM
Quote:
My concern is how to return the valve body?
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12-24-2023, 12:44 PM | #43 |
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Re: Shifting at high RPM
It only goes in 1 way. It'll or should pull straight out with a magnet. Just a steel valve. Same as the governor valve it should slide in and out smoothly
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12-24-2023, 01:05 PM | #44 | |
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Re: Shifting at high RPM
Quote:
What should I look 👀 for when I pull it out?🫡 Will it leak oil? Because I put in 1.6L of trans oil yesterday to replace the oil that came out of governor area 🥱
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12-24-2023, 04:12 PM | #45 |
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Re: Shifting at high RPM
I managed to pull the valve out with a magnet as suggested, initially it did come out smoothly, I pushed it back with the magnet then out, I checked it, nothing noticeable, cleaned it then with the magnet I pushed in and out three times, it was very smooth.
Took the truck out for a drive, same issue will not shift. 🥱🥱🥱 I suspect that the vacuum modulator is the issue, but I’m no expert.😎 Someone said maybe the clutch’s are gone, but I’m no expert, that’s why I’m here.🤔🇶🇦🇶🇦 Out of ideas 🤒😏
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12-24-2023, 08:50 PM | #46 |
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Re: Shifting at high RPM
Considering the rest of your truck collection do you possibly have a modulator you could borrow to see if it is indeed the modulator?
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12-25-2023, 06:00 AM | #47 |
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Re: Shifting at high RPM
I did consider that, however all my trucks are manual,
I’ll try to find someone that can lend me his modulator, No parts available in my country for such trucks. I have to buy it from the USA via eBay, SummitRacing, Rock Auto, Jets, and others, and hopefully they arrive un damaged, and they are the correct ones, after 4-6 weeks from ordering
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12-27-2023, 07:30 PM | #48 |
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Re: Shifting at high RPM
FWIW, I've changed my TH400 modulator 4 times in 20k miles. The units you buy nowadays are not so good.
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12-27-2023, 07:49 PM | #49 |
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Re: Shifting at high RPM
I’ve never changed any of mine. Unfortunately most are made in China, and different brands, not knowing which ones will fit, and they sometimes don’t work
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12-29-2023, 01:12 AM | #50 | |
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Re: ****ing at high RPM
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