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Old 12-30-2023, 01:32 PM   #1
Shifty One
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Re: Shifting at high RPM

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Originally Posted by cadillac_al View Post
I still think it will be something simple when you find it. just my .02
Agreed.
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Old 12-30-2023, 01:45 PM   #2
Captain J
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Re: Shifting at high RPM

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Originally Posted by Shifty One View Post
Agreed.
Always the simple and obvious things get you
But what is?


I’m still waiting to know the reason of oil spillage?
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Old 12-30-2023, 02:21 PM   #3
kwmech
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Re: Shifting at high RPM

Oil level in the transmission while running is approximately at the oil pan gasket level. Vacuum Modulator is above the pan. If the truck sits for any amount of time the torque convertor will drain out some raising the level in the pan until you start the truck again. So to answer your question...it depends.
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Old 12-30-2023, 02:45 PM   #4
Captain J
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Re: Shifting at high RPM

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Originally Posted by kwmech View Post
Oil level in the transmission while running is approximately at the oil pan gasket level. Vacuum Modulator is above the pan. If the truck sits for any amount of time the torque convertor will drain out some raising the level in the pan until you start the truck again. So to answer your question...it depends.
It’s possible,
But still the issue isn’t resolved
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1972 GMC Sierra C2500, V8-350
1986 GMC Sierra C2500, V8-454
1986 GMC Sierra C2500, V8-LS1
1986 GMC Sierra K2500, V8-350
1987 GMC Sierra R3500, V8-454
1997 GMC Sierra K2500, V8-454
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Old 12-30-2023, 03:49 PM   #5
kwmech
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Re: Shifting at high RPM

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Originally Posted by Captain J View Post
It’s possible,
But still the issue isn’t resolved
Yeah, I know. Kinda hard to diagnose over the internet without having hands on. We did hit the basics. I'm still thinking of a sticking valve in the valve body. The person to ask ---who is no longer here--- is clinebarger. He was really good on these maters
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Old 12-31-2023, 09:48 AM   #6
Captain J
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Re: Shifting at high RPM

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Originally Posted by kwmech View Post
Yeah, I know. Kinda hard to diagnose over the internet without having hands on. We did hit the basics. I'm still thinking of a sticking valve in the valve body. The person to ask ---who is no longer here--- is clinebarger. He was really good on these maters
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.
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1972 GMC Sierra C2500, V8-350
1986 GMC Sierra C2500, V8-454
1986 GMC Sierra C2500, V8-LS1
1986 GMC Sierra K2500, V8-350
1987 GMC Sierra R3500, V8-454
1997 GMC Sierra K2500, V8-454
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Old 01-04-2024, 12:22 PM   #7
GRADYS Performance
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Re: Shifting at high RPM

Quote:
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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