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Transmission Oil Leak [message #174085] Wed, 20 June 2012 16:57 Go to next message
bess is currently offline  bess   United States
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Can someone please give me advice on a Transmission Oil Leak. The First of May, I noticed a puddle of Transmission Oil under the GMC. It was dripping from the Pan. I took it to my Mechanic & he put a New Gasket on the Transmission Pan and Changed the Filter and I picked it up on May 11th and had No further leaks. I went on a short trip the following week, just a couple hundred miles, brought it home & it has been sitting since May 18th with No Leaks. A couple of days ago - again, Transmission Oil under her. This time it was not coming from the Pan but from in front of the Pan. I put something under the Motorhome to catch the oil and in 24 hours, it had about a 1/2 Cup. I raised the Motor Hatch and tried to find out where it is leaking. Down at the Bottom of the Dip Stick I got a handfull of Transmission Oil. Cold, the Dip Stick reads way above the Full. I started it up and let it warm up and took several readings because it was hard to see the Oil. Someone has put a black mark across the dip stick where it says full which doesn't look original. Warm, the Oil is under this mark just a little. On the back side of the stick there are 2 dots and the oil is above these dots. Toward the bottom of the Dip Stick, there is hardly Any Oil At All. Can you give me some ideas as to where this Transmission Oil is coming from?

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: Transmission Oil Leak [message #174086 is a reply to message #174085] Wed, 20 June 2012 17:05 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Its leaking down from your torque converter.

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 Oil Leak [message #174087 is a reply to message #174085] Wed, 20 June 2012 17:14 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
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As Bruce has offered -- it is most lilely the torque converter leaking down.

Some transmissions do this and some less so. As it leaks down the level shown on the dipstick rises -- that is why the instructions are to check it hot (engine running usually).

The external leak onto your drive is most likely the dipstick tube leaking where it is pressed into the transmission body. There is a bolt that holds it tight -- could be loose.

The black mark could be a previous owners "calibration" of full.


bess wrote on Wed, 20 June 2012 16:57

Can someone please give me advice on a Transmission Oil Leak. The First of May, I noticed a puddle of Transmission Oil under the GMC. It was dripping from the Pan. I took it to my Mechanic & he put a New Gasket on the Transmission Pan and Changed the Filter and I picked it up on May 11th and had No further leaks. I went on a short trip the following week, just a couple hundred miles, brought it home & it has been sitting since May 18th with No Leaks. A couple of days ago - again, Transmission Oil under her. This time it was not coming from the Pan but from in front of the Pan. I put something under the Motorhome to catch the oil and in 24 hours, it had about a 1/2 Cup. I raised the Motor Hatch and tried to find out where it is leaking. Down at the Bottom of the Dip Stick I got a handfull of Transmission Oil. Cold, the Dip Stick reads way above the Full. I started it up and let it warm up and took several readings because it was hard to see the Oil. Someone has put a black mark across the dip stick where it says full which doesn't look original. Warm, the Oil is under this mark just a little. On the back side of the stick there are 2 dots and the oil is above these dots. Toward the bottom of the Dip Stick, there is hardly Any Oil At All. Can you give me some ideas as to where this Transmission Oil is coming from?



Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: Transmission Oil Leak [message #174089 is a reply to message #174087] Wed, 20 June 2012 17:29 Go to previous messageGo to next message
bess is currently offline  bess   United States
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With No Oil Showing on the Bottom of the Dip Stick and only oil showing at the top when it is checked warm, is it Safe to Drive like it is or should I find someone to Fix It. I can't take it to my mechanic as he is having Surgery tomarrow.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: Transmission Oil Leak [message #174090 is a reply to message #174087] Wed, 20 June 2012 17:29 Go to previous messageGo to next message
armandminnie is currently offline  armandminnie   United States
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I had a transmission leak and thought that it was the dipstick tube where it enters the final drive. It turns out that there is a little 'weep' hole in the final drive right next to the dipstick tube. If one of the two seals that separate the final drive from the transmission is leaking it will come out of that hole. That is where my transmission was actually leaking. How that relates to Bess' problem I have no idea.

Bess, it sounded like your coach sat for a month or so with no leak and, without even driving it, it suddenly leaked? Is that correct?


Armand Minnie
Marana, AZ
'76 Eleganza II TZE166V103202
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Re: Transmission Oil Leak [message #174092 is a reply to message #174089] Wed, 20 June 2012 17:33 Go to previous messageGo to next message
armandminnie is currently offline  armandminnie   United States
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Bess, you are checking the transmission level with the engine running? I have found that the back of my dipstick shows the level when the front is an unreadable mess.

Armand Minnie
Marana, AZ
'76 Eleganza II TZE166V103202
visit my gmc blog
click here to visit gmcws.org
Re: Transmission Oil Leak [message #174093 is a reply to message #174090] Wed, 20 June 2012 17:35 Go to previous messageGo to next message
bess is currently offline  bess   United States
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Hi, Yes that is right. Both times that the Transmission started leaking were the same way. This last time, it has sat since May 18th in the same spot on the driveway and I hadn't started her and she just started leaking all of a sudden.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: Transmission Oil Leak [message #174094 is a reply to message #174093] Wed, 20 June 2012 17:38 Go to previous messageGo to next message
armandminnie is currently offline  armandminnie   United States
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That is strange to say the least. All I can think of to ask is about the weather - temperature spikes, pressure changes. Something had to change.

Armand Minnie
Marana, AZ
'76 Eleganza II TZE166V103202
visit my gmc blog
click here to visit gmcws.org
Re: Transmission Oil Leak [message #174095 is a reply to message #174092] Wed, 20 June 2012 17:40 Go to previous messageGo to next message
bess is currently offline  bess   United States
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Yes, I am checking it with the engine running. I checked it both on the front of the dip stick as well as the back and I can't see any oil toward the bottom of the dip stick - only up farther. I did check it without the engine running as well and you can see the oil from the bottom of the stick up past the full.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: Transmission Oil Leak [message #174096 is a reply to message #174094] Wed, 20 June 2012 17:51 Go to previous messageGo to next message
bess is currently offline  bess   United States
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This is the Part that I don't understand. . . Both of the Transmission Leaks I have had - has been when the Coach is sitting for several weeks. It just starts leaking on it's own. The only thing that has changed is that the temperature here has went up 10 or 15 degrees.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: Transmission Oil Leak [message #174097 is a reply to message #174095] Wed, 20 June 2012 17:51 Go to previous messageGo to next message
armandminnie is currently offline  armandminnie   United States
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Sounds like you are low on fluid. It seems it would have had to leak an awful lot of oil to be that low that it doesn't show on the dipstick (bottom), either that or your mechanic didn't fill it all the way after the pan and filter job. Either way, from your description of the sequence, you came back from that short trip without any sign of leaks and now it is several pints low. I would definitely fill it before any more traveling - making sure to check the level hot so you don't overfill it.

Armand Minnie
Marana, AZ
'76 Eleganza II TZE166V103202
visit my gmc blog
click here to visit gmcws.org
Re: [GMCnet] Transmission Oil Leak [message #174100 is a reply to message #174097] Wed, 20 June 2012 18:25 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Armand,

Did you see this email?

If it is up past full it is overfilled!

Regards,
Rob

-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Bes Brenenstall
Sent: Thursday, 21 June 2012 8:41 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Transmission Oil Leak

Yes, I am checking it with the engine running.

I checked it both on the front of the dip stick as well as the back and I can't see any oil toward the bottom of the dip stick -
only up farther.

I did check it without the engine running as well and you can see the oil from the bottom of the stick up past the full.
--
Bess Brenenstall
Elvaston, Illinois
1976 Birchaven

-----Original Message-----
From: Armand Minnie

Sounds like you are low on fluid. It seems it would have had to leak an awful lot of oil to be that low that it doesn't show on the
dipstick (bottom), either that or your mechanic didn't fill it all the way after the pan and filter job. Either way, from your
description of the sequence, you came back from that short trip without any sign of leaks and now it is several pints low. I would
definitely fill it before any more traveling - making sure to check the level hot so you don't overfill it.
--
Armand

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Transmission Oil Leak [message #174102 is a reply to message #174100] Wed, 20 June 2012 18:29 Go to previous messageGo to next message
armandminnie is currently offline  armandminnie   United States
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Rob, the 'past full' was without the engine running. When it is running the dipstick apparently shows nothing at the bottom and some scattered oil elsewhere. The torque converter leaks down and makes the dipstick show oil when it is not running.

Armand Minnie
Marana, AZ
'76 Eleganza II TZE166V103202
visit my gmc blog
click here to visit gmcws.org
Re: [GMCnet] Transmission Oil Leak [message #174104 is a reply to message #174085] Wed, 20 June 2012 18:35 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Bes,

I store Double Trouble for eight months a year and found that there is always oil under the transmission. I got a cardboard box that
was a bit bigger than the transmission pan and put an inch or two of Fullers earth (clay cat litter ) in it and slid it under the
transmission.

As far as the black mark on the dipstick goes someone could have calibrated the dipstick by removing the modulator and filling it
until fluid dripped out of the fitting and then marking the dip stick with the black mark.

Regards,
Rob M.

-----Original Message-----
From: Bes Brenenstall

Can someone please give me advice on a Transmission Oil Leak. The First of May, I noticed a puddle of Transmission Oil under the
GMC. It was dripping from the Pan. I took it to my Mechanic & he put a New Gasket on the Transmission Pan and Changed the Filter
and I picked it up on May 11th and had No further leaks. I went on a short trip the following week, just a couple hundred miles,
brought it home & it has been sitting since May 18th with No Leaks. A couple of days ago - again, Transmission Oil under her. This
time it was not coming from the Pan but from in front of the Pan. I put something under the Motorhome to catch the oil and in 24
hours, it had about a 1/2 Cup. I raised the Motor Hatch and tried to find out where it is leaking. Down at the Bottom of the Dip
Stick I got a handfull of Transmission Oil. Cold, the Dip Stick reads way above the Full. I started it up and let it warm up and
took several readings because it was hard to see the Oil. Someone has put a black mark across the dip stick where it says full which
doesn't look original. Warm, the Oil is under this mark just a little. On the back side of the stick there are 2 dots and the oil is
above these dots. Toward the bottom of the Dip Stick, there is hardly Any Oil At All. Can you give me some ideas as to where this
Transmission Oil is coming from?
--
Bess

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: Transmission Oil Leak [message #174107 is a reply to message #174096] Wed, 20 June 2012 18:48 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
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bess wrote on Wed, 20 June 2012 15:51

This is the Part that I don't understand. . . Both of the Transmission Leaks I have had - has been when the Coach is sitting for several weeks. It just starts leaking on it's own. The only thing that has changed is that the temperature here has went up 10 or 15 degrees.

Mine does It, too. Torque converter leaks down into the trans pushing it way past full. I have had trouble with my dip stick tube leaking. I thought I had it fixed, only to have it leak after sitting a few weeks.

After my dad died, his pickup sat in AZ for months at a time. I had to add almost a quart every time I got there, to even back it out of the garage. The whole time I was ther,using it in getting the house ready to sell, it never leaked a drop. Park it for a few months and it was low again with oil all over the floor.

As far as driving it low, I would see if it goes into gear when you shift into drive. If it does, it is not super low. Then check it again, running and perhaps add a little... Like the cup that ran out. If you ar going to have it on hills you want it full. If you are only taking it to town to have the dip stick tube checked, and will go without slipping, ease it into town.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: [GMCnet] Transmission Oil Leak [message #174116 is a reply to message #174102] Wed, 20 June 2012 19:24 Go to previous message
USAussie is currently offline  USAussie   United States
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Armand,

Got it, I was confoosed by the wording.

Regards,
Rob M.
 
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Armand Minnie

Rob, the 'past full' was without the engine running. When it is running the dipstick apparently shows nothing at the bottom and some
scattered oil elsewhere. The torque converter leaks down and makes the dipstick show oil when it is not running.
--
Armand

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
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