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Old 12-31-2023, 11:33 AM   #76
geezer#99
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Re: Shifting at high RPM

Try this.


https://www.gtoforum.com/threads/hel...140685&slide=0
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Old 12-31-2023, 11:51 AM   #77
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Re: Shifting at high RPM

Quote:
Originally Posted by geezer#99 View Post
I didn’t see a connector similar to the pic on the right side (driver side)
The only connector is coming from the 4x4 firewall to the top left side, I think it’s for 4x4 engagement and light,
See pictures
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Old 12-31-2023, 12:05 PM   #78
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Re: Shifting at high RPM

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Originally Posted by Captain J View Post
I didn’t see a connector similar to the pic on the right side (driver side)
The only connector is coming from the 4x4 firewall to the top left side, I think it’s for 4x4 engagement and light,
See pictures
Here are the pictures
Hopefully I can load it
Attached Images
 
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Old 12-31-2023, 12:06 PM   #79
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Re: Shifting at high RPM

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Originally Posted by Captain J View Post
Here are the pictures
Hopefully I can load it
Pictures are attached,
The website will not allow me to upload more than 2, or it keeps say your message is toooooo short
Attached Images
  
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Old 12-31-2023, 12:15 PM   #80
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Re: Shifting at high RPM

Quote:
Originally Posted by Captain J View Post
Here are the pictures
Hopefully I can load it
That first pic shows the switch.
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Old 12-31-2023, 12:19 PM   #81
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Re: Shifting at high RPM

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Originally Posted by geezer#99 View Post
That first pic shows the switch.
I did disconnected it, as I mentioned before, nothing.
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Old 01-04-2024, 10:24 AM   #82
Captain J
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Re: Shifting at high RPM

Any ideas?
I’m not getting any luck with this trans.
I managed to get me a vacuum gauge but I’m not sure what to do or to look for?
Any suggestions
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Old 01-04-2024, 10:27 AM   #83
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Re: Shifting at high RPM

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Originally Posted by Dead Parrot View Post
What is your idle vacuum reading? Also check at the hose going into the modulator.

If your vacuum is low, it will make the modulator act like you are really into the throttle and keep the trans from shifting.

I managed to get me a vacuum gauge, but I don’t know how to use it, or where to connect it? Plus what to look for?


Check the kickdown switch and make sure it isn't stuck on. If it is stuck, it is telling the trans you are at near WOT and will also keep it in lower gear.
It’s working, I disconnected the switch from the transmission, no change
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Old 01-04-2024, 12:22 PM   #84
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Re: Shifting at high RPM

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Originally Posted by Captain J View Post
Yeah I know, but you guys helped me a lot, I appreciate that
The question is when I replaced the vacuum modulator the second time and oil came pouring out, 1. Where this oil coming from, I mean what opening?
Why the valve didn’t come out?
I tried to drive in D1 and D2 to see if any changes, nothing.
As stated in an earlier post, The oil level rises in the transmission as the fluid drains from the torque converter back into the transmission the longer it sits.
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Old 01-04-2024, 12:24 PM   #85
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Re: Shifting at high RPM

Quote:
Originally Posted by Captain J View Post
Here are the pictures
Hopefully I can load it
Did you disconnect the orange wire that went to the transmission in this picture?
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Old 01-04-2024, 12:38 PM   #86
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Re: Shifting at high RPM

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Originally Posted by GRADYS Performance View Post
Did you disconnect the orange wire that went to the transmission in this picture?
Yes I did and nothing still will not shift from 1st gear
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Old 01-04-2024, 12:39 PM   #87
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Re: Shifting at high RPM

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Originally Posted by GRADYS Performance View Post
As stated in an earlier post, The oil level rises in the transmission as the fluid drains from the torque converter back into the transmission the longer it sits.
I see, so to avoid any spillage I should start the truck for few minutes
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Old 01-04-2024, 12:43 PM   #88
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Re: Shifting at high RPM

What if anything does the transmission do? What happens when you try to drive it, Forward shifter in D? 2nd? 1st? What happens with shifter in reverse?
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Old 01-04-2024, 12:53 PM   #89
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Re: Shifting at high RPM

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Originally Posted by GRADYS Performance View Post
What if anything does the transmission do? What happens when you try to drive it, Forward shifter in D? 2nd? 1st? What happens with shifter in reverse?
All shiftin in R, D, 2ed, 1st are working, truck will move nicely in R or D, 1, 2.
The only issue is shifting from 1st to 2ed.

I’m picking my brain on what happens from before painting the truck and replacing the valve stems, to now. No one worked on the trans, or the manifold, only the valves.
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Old 01-04-2024, 12:56 PM   #90
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Re: Shifting at high RPM

When it is in Drive or 2nd when you start out does it ever shift or does it just stay in 1st gear? When in Reverse it moves normally?
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Old 01-04-2024, 12:58 PM   #91
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Re: Shifting at high RPM

When you removed vacum modulator did you take the valve out behind the modulator? Did it move freely if you took it out and replaced it?
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Old 01-04-2024, 01:13 PM   #92
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Re: Shifting at high RPM

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Originally Posted by GRADYS Performance View Post
When it is in Drive or 2nd when you start out does it ever shift or does it just stay in 1st gear? When in Reverse it moves normally?
It just stay in 1st.
In reverse it’s normal, I did try in 2ed but didn’t notice it shifted
I’ll check and see

Wow
In 2ed it did shift from 1 to 2 so smoothly I barely notice it,
I put it in D and I think it shifted from 1 to 2,

Tomorrow I’ll do full test and I’ll update you
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Last edited by Captain J; 01-04-2024 at 01:46 PM.
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Old 01-04-2024, 01:19 PM   #93
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Re: Shifting at high RPM

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Originally Posted by GRADYS Performance View Post
When you removed vacum modulator did you take the valve out behind the modulator? Did it move freely if you took it out and replaced it?
Initially I thought it’s sticking (I’m no expert to judge on how smooth it should be), I fished it out with a magnet and it took 3-4 times to remove it, (I posted pictures of the valve) when I put it back it was moving in and out easily.
Unless I’m not doing it correctly ( using a magnet),
First time no oil came out just few drops, second time about 2ltr came gushing out.
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Old 01-08-2024, 05:26 AM   #94
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Re: Shifting at high RPM

Greetings to you all for helping out in my truck gear issue.
Update
I test drive the truck last night, and it shifts in all gears, I don’t know what happened, but it’s working fine,
Again, thank you all for your suggestions and recommendations, I wish I knew what was wrong with the tranny.
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Old 01-08-2024, 12:23 PM   #95
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Re: Shifting at high RPM

Probably a piece of that silicone
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Old 01-08-2024, 12:39 PM   #96
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Re: Shifting at high RPM

Quote:
Originally Posted by kwmech View Post
Probably a piece of that silicone
I have no clue, but it’s working now and that’s important.
Maybe the gremlins were there
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Old 01-09-2024, 11:08 AM   #97
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Re: Shifting at high RPM

I figured it would be something simple lol. It probable was the sticking modulator valve. They are supposed to slide out easily. I didn't think we were going to get any further with the diagnosis without an actual vacuum reading at the modulator. Happy ending anyway.
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Old 01-09-2024, 11:56 AM   #98
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Re: Shifting at high RPM

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Originally Posted by cadillac_al View Post
I figured it would be something simple lol. It probable was the sticking modulator valve. They are supposed to slide out easily. I didn't think we were going to get any further with the diagnosis without an actual vacuum reading at the modulator. Happy ending anyway.
Things are always simple, but we sometimes complicate it. Like the mechanic who told me the clutches are gone, you need new trans, and I’ve a used one.

Regarding the vacuum readings, what is the correct reading in psi?

Yeah happy ending
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Old 01-09-2024, 02:28 PM   #99
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Re: Shifting at high RPM

manifold vacuum at the end of the hose 14-15 inches ----ish
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Old 01-09-2024, 02:40 PM   #100
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Re: Shifting at high RPM

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Originally Posted by kwmech View Post
manifold vacuum at the end of the hose 14-15 inches ----ish
Ok, I’ll check
Thanks
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