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Transmission leak [message #349071] Tue, 08 October 2019 12:49 Go to next message
tgeiger is currently offline  tgeiger   United States
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Registered: February 2006
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Ok, so I've done everything I was told to to get this transmission pan to stop leaking and it hasn't. Still leaving puddles on my driveway. Started up this morning and it would not engage in drive so apparently its low on fluid. Just started this so how much fluid would you expect I need to put in it? I'm planning on ordering a vented aluminum pan from Jim after camping is finished this season.

Tom
76 Eleganza 2
Kansas City, Mo


Tom Geiger 76 Eleganza II KCMO
Re: [GMCnet] Transmission leak [message #349075 is a reply to message #349071] Tue, 08 October 2019 14:07 Go to previous messageGo to next message
Mike Kelley is currently offline  Mike Kelley   United States
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Up to the full line on the dipstick while engine is running and tranny up to normal operating temp.
Mike/The Corvair a holic

Sent from my iPhone

> On Oct 8, 2019, at 1:49 PM, tom geiger via Gmclist wrote:
>
> Ok, so I've done everything I was told to to get this transmission pan to stop leaking and it hasn't. Still leaving puddles on my driveway. Started up
> this morning and it would not engage in drive so apparently its low on fluid. Just started this so how much fluid would you expect I need to put in
> it? I'm planning on ordering a vented aluminum pan from Jim after camping is finished this season.
>
> Tom
> 76 Eleganza 2
> Kansas City, Mo
>
> _______________________________________________
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Re: [GMCnet] Transmission leak [message #349076 is a reply to message #349075] Tue, 08 October 2019 14:28 Go to previous messageGo to next message
Deb is currently offline  Deb   Canada
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Registered: October 2016
Location: Logan Lake, BC
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If you have a copy of the maintenance manual on page 7-27 (Transmission) it gives the expected levels at various temps. It's hard to get it to operating temperature if you can't drive it, I would imagine.
If it has been parked and isn't running, you would expect the level to be well above the FULL mark - a couple of inches.
Let the engine run a few minutes and shift the transmission through it's gears to get the fluid moving and into it's proper place Smile

This is directly from the Maintenance Manual 75-76 X7525 (won't be in the 77-78 supplement, if that's all you have)

With your fingers, Check the temperature of the end of your dipstick. Note that this is with the engine idling and the tranny in Park, of course.

At room temp (cool to the touch) - should be between 1/8 - 3/8" below the ADD mark
If it's warm (not hot) should be close to the ADD mark (slightly above or below)
If Hot (can't hold it comfortably) then it should be between the ADD & FULL marks.

Theres a chart on 7-28 that shows where you would expect it to be at various temps. I printed it out and added it to my manual supplement for reference. I have just gone through leaking tranny diagnostics and repair. It came in handy.




Deb McWade Logan Lake, BC, CAN GMC Alumnus It's Bigger on the Inside!

[Updated on: Tue, 08 October 2019 14:29]

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Re: Transmission leak [message #349080 is a reply to message #349071] Tue, 08 October 2019 16:27 Go to previous messageGo to next message
Scott Nutter is currently offline  Scott Nutter   United States
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Tom,
Are you sure it's the pan? Maybe Speedo gear/cable, modulator, or even the o ring at the dip stick, or even tranny cooler lines? Seems like a lot of fluid to be seeping out of a semi porous aluminum pan..
Scott.


Scott Nutter 1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final drive, Quad bags, Dave Lenzi super duty mid axle disc brakes, tankless water heater, everything Lenzi. Alex Ferrera installed MSD Atomic EFI Houston, Texas
Re: [GMCnet] Transmission leak [message #349088 is a reply to message #349080] Tue, 08 October 2019 20:26 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
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Senior Member
I feel Scott is correct in addressing the other things.
The Modulator , as it is in the fluid level.
Does the leak develop after it has been prked forcouple days? If so the
fill tube at the final drive is alwys a suspect.

On Tue, Oct 8, 2019 at 2:28 PM Scott Nutter via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Tom,
> Are you sure it's the pan? Maybe Speedo gear/cable, modulator, or even
> the o ring at the dip stick, or even tranny cooler lines? Seems like a
> lot
> of fluid to be seeping out of a semi porous aluminum pan..
> Scott.
> --
> Scott Nutter
> 1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final
> drive, Quad bags, tankless water heater, everything Lenzi. Alex Ferrera
> installed MSD Atomic EFI
> Houston, Texas
>
> _______________________________________________
> 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: Transmission leak [message #349091 is a reply to message #349071] Tue, 08 October 2019 20:30 Go to previous message
tgeiger is currently offline  tgeiger   United States
Messages: 518
Registered: February 2006
Location: kansas city
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Senior Member
Great info guys. I'll let it warm up and check the level. Refill will be base on temp guidlines. Great info

Thanks,
TG


Tom Geiger 76 Eleganza II KCMO
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