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Transmission filter change, how much fluid will I need? [message #343645] Sat, 25 May 2019 06:58 Go to next message
RF_Burns is currently offline  RF_Burns   Canada
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I've search around and I know it should be on here somewhere, but I haven't been able to find it.

Can anyone tell me how much transmission fluid I'll need when changing a transmission filter? I'll be fixing the leak in shifter shaft at the same time so I'll have the pan open for several hours if that makes any difference.

Thanks.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Transmission filter change, how much fluid will I need? [message #343646 is a reply to message #343645] Sat, 25 May 2019 07:31 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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RF_Burns wrote on Sat, 25 May 2019 07:58
I've search around and I know it should be on here somewhere, but I haven't been able to find it.

Can anyone tell me how much transmission fluid I'll need when changing a transmission filter? I'll be fixing the leak in shifter shaft at the same time so I'll have the pan open for several hours if that makes any difference.

Thanks.
Bruce,
If the trans has been shut down for a couple of hours, it won't drain down much more, but it will store 5~6 quarts mostly in the torque converter. So, if you take the pan down, expect a minimum of four and maybe as much as six. When I last changed a filter, I had four on hand, but it ended up needed a couple more.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Transmission filter change, how much fluid will I need? [message #343653 is a reply to message #343645] Sat, 25 May 2019 10:47 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Matt,
Forgot I also have a Ragusa transmission pan, so that holds a bit more. So I best get 8 litres to be safe.

Thanks


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: [GMCnet] Transmission filter change, how much fluid will I need? [message #343655 is a reply to message #343653] Sat, 25 May 2019 10:52 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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It depends on each case.
Dump in 4 and run engine for couple min and see.
Fill only to Add line as trans is cold.

On Sat, May 25, 2019 at 8:48 AM Bruce Hislop via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Matt,
> Forgot I also have a Ragusa transmission pan, so that holds a bit more. So
> I best get 8 litres to be safe.
>
> Thanks
>
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Transmission filter change, how much fluid will I need? [message #343656 is a reply to message #343653] Sat, 25 May 2019 11:23 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Sam, my transmission go to guy, says "If your transmission shows full on
the stick, then, capture the drained fluid, measure what you drain, and
return that much to the transmission when you refill it..
Jim Hupy


On Sat, May 25, 2019 at 8:48 AM Bruce Hislop via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Matt,
> Forgot I also have a Ragusa transmission pan, so that holds a bit more. So
> I best get 8 litres to be safe.
>
> Thanks
>
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: [GMCnet] Transmission filter change, how much fluid will I need? [message #343658 is a reply to message #343645] Sat, 25 May 2019 12:07 Go to previous messageGo to next message
Tangerine is currently offline  Tangerine   United States
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On 5/25/2019 7:58 AM, Bruce Hislop via Gmclist wrote:
> I've search around and I know it should be on here somewhere, but I haven't been able to find it.
>
> Can anyone tell me how much transmission fluid I'll need when changing a transmission filter? I'll be fixing the leak in shifter shaft at the same
> time so I'll have the pan open for several hours if that makes any difference.
>
> Thanks.
>
Bruce

How bad of a leak did you have with the shifter shaft seal?  Mine is
leaking, a lot. I was wondering if it could be this seal, or is
something else leaking also. I lost 4 quarts in 200 miles.

Matt

I the trans fluid under pressure at the shift shaft seal?  Could I be
loosing that much oil there?

--
Gary W. Mills
Livonia, MI
. ___________
./_][__][] []| 1974 GMC M/H
.*O-------OO-* Painted Desert


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1974 GMC 260
Tangerine Dream
Livonia Michigan
Re: [GMCnet] Transmission filter change, how much fluid will I need? [message #343661 is a reply to message #343658] Sat, 25 May 2019 14:05 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Tangerine wrote on Sat, 25 May 2019 13:07
Bruce

How bad of a leak did you have with the shifter shaft seal?  Mine is
leaking, a lot. I was wondering if it could be this seal, or is
something else leaking also. I lost 4 quarts in 200 miles.

Matt

I the trans fluid under pressure at the shift shaft seal?  Could I be
loosing that much oil there?

--
Gary W. Mills
Livonia, MI
Gary,

I haven't looked up in there in years, but as I recall, that shift control is in the outer space. That means that the only pressure on it should be the same case pressure as the dipstick aka not much.
I would suggest that if it is leaking that much, you locate the leak before you do much else.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Transmission filter change, how much fluid will I need? [message #343662 is a reply to message #343661] Sat, 25 May 2019 14:12 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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If you have a remote dipstick, it is very possible that your transmission
is overfilled. If it is, you will blow fluid out of places that would
normally not leak if the level were correct.
Jim Hupy

On Sat, May 25, 2019, 12:06 PM Matt Colie via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Tangerine wrote on Sat, 25 May 2019 13:07
>> Bruce
>>
>> How bad of a leak did you have with the shifter shaft seal? Mine is
>> leaking, a lot. I was wondering if it could be this seal, or is
>> something else leaking also. I lost 4 quarts in 200 miles.
>>
>> Matt
>>
>> I the trans fluid under pressure at the shift shaft seal? Could I be
>> loosing that much oil there?
>>
>> --
>> Gary W. Mills
>> Livonia, MI
>
> Gary,
>
> I haven't looked up in there in years, but as I recall, that shift control
> is in the outer space. That means that the only pressure on it should be
> the same case pressure as the dipstick aka not much.
> I would suggest that if it is leaking that much, you locate the leak
> before you do much else.
>
> Matt
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: Transmission filter change, how much fluid will I need? [message #343667 is a reply to message #343645] Sat, 25 May 2019 16:59 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Gary,
My shifter shaft always leaked a little bit, but when I moved it out of the shop for the day and then put it back, next day there was a couple of tablespoons worth on the floor. Paula has taken over my entire shop with her furniture refinishing lately so for a few days I was moving it out every morning and back inside in the evening. Now I just leave it outside.

However since taking it for a spin into town for gas, the leak seems to have slowed. I was able to put it back in today due to severe storms passing through. I'll check the pan I put under it tomorrow and see how much its still leaking.

As for the shifter shaft seal, while the TH400 and others have a metal encased seal, the TH425 appears to only have an O-ring. Wipe the pan clean and it soon shows if its the shifter shaft leaking. From what I can see, the shaft is above the ATF level while driving, however when sitting and leaking down, the ATF level is above the shaft. There is no pressurized ATF on the shaft.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Transmission filter change, how much fluid will I need? [message #343678 is a reply to message #343645] Sun, 26 May 2019 05:40 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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Well, if the converter leaks down, will that raise the level in the pan above the shift lever shaft?

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: Transmission filter change, how much fluid will I need? [message #343680 is a reply to message #343645] Sun, 26 May 2019 06:57 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Johnny,
Yes, it raises the fluid by a couple of inches, well above the shifter shaft.

Not sure if replacing this O-ring seal will fix the leak as I'm sure the housing and the shaft are worn a bit after 40yrs.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Transmission filter change, how much fluid will I need? [message #343754 is a reply to message #343645] Tue, 28 May 2019 12:25 Go to previous message
jhbridges is currently offline  jhbridges   United States
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This would explain why there's leaks sitting but not so much on the road.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
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