Loosing Tranny fluid follow-up

H

heinz wittenbecher

New member
Mar 1, 1998
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Background:
Changed filters, fluid and pan. Pan was replaced due to rock damage.

First trip around the block lost fluid. Actually had to add a quart to get
back in the barn.

Fluid was litterally running out on shutdown.

Investigation revealed that the fluid actually came out via the vent. (No,
not overfilled).
Confirmed by simply running it for a bit and shutting it off.

Dropped the pan and replaced the new Fram filter and O-ring with another new
Fram filter and O-ring.

Just came back from the test circuit and ALL SEEMS WELL.

Hopefully it'll remain well. Little bigger testflight this weekend.

Moral of the story (if there is one): Keep looking for leaks even after
engine shutdown when doing a tranny/filter service.

Heinz
www.my-gmc.com
 
what is this???

new filter, how can this be????

did your over flow pipe keep the oil off of the exhaust ??

gene

>Background:
>Changed filters, fluid and pan. Pan was replaced due to rock damage.
>
>First trip around the block lost fluid. Actually had to add a quart to get
>back in the barn.
>
>Fluid was litterally running out on shutdown.
>
>Investigation revealed that the fluid actually came out via the vent. (No,
>not overfilled).
>Confirmed by simply running it for a bit and shutting it off.
>
>Dropped the pan and replaced the new Fram filter and O-ring with another new
>Fram filter and O-ring.
>
>Just came back from the test circuit and ALL SEEMS WELL.
>
>Hopefully it'll remain well. Little bigger testflight this weekend.
>
>Moral of the story (if there is one): Keep looking for leaks even after
>engine shutdown when doing a tranny/filter service.
>
>Heinz
>www.my-gmc.com
>
>
>
>
>
>
Genef -- 77PB/ore/ca
GMC MOTORHOME INFORMATION
mr.erf
http://www.california.com/~eagle/
 
> what is this???
>
> new filter, how can this be????

They just don't make 'em like they used to I guess.
Only other cause could be the modulator acting up but not likely as we had
the overflow, changed filter, no more overflow. Would be a real coincidence
if modulator became unstuck or something at just that time and I don't know
if modulator failure could cause an overflow problem. I think/thought
modulator problem would 'swallow/burn' tranny fluid. According to the
troubleshooting guide foaming could've caused my symptoms and foaming could
be caused by bad or improperly fitting filter.
>
>
> did your over flow pipe keep the oil off of the exhaust ??

I still have the original vent setup so it ran down the acse on the drivers
side. No smoke or smell so I would guess it missed exhaust. Vent pipe mod is
on the list at engine time.

Heinz

>
> gene
>

> >Background:
> >Changed filters, fluid and pan. Pan was replaced due to rock damage.
> >
> >First trip around the block lost fluid. Actually had to add a quart to
get
> >back in the barn.
> >
> >Fluid was litterally running out on shutdown.
> >
> >Investigation revealed that the fluid actually came out via the vent.
(No,
> >not overfilled).
> >Confirmed by simply running it for a bit and shutting it off.
> >
> >Dropped the pan and replaced the new Fram filter and O-ring with another
new
> >Fram filter and O-ring.
> >
> >Just came back from the test circuit and ALL SEEMS WELL.
> >
> >Hopefully it'll remain well. Little bigger testflight this weekend.
> >
> >Moral of the story (if there is one): Keep looking for leaks even after
> >engine shutdown when doing a tranny/filter service.
> >
> >Heinz
> >www.my-gmc.com
> >
> >
> >
> >
> >
> >
> Genef -- 77PB/ore/ca
> GMC MOTORHOME INFORMATION
> mr.erf
> http://www.california.com/~eagle/
>
 
Ventured out of the "circuit" today and still no panic overflow on landing.

Gonna assume all is back to normal and head over the Coqahalla next week. if
it ain't right it'll sure show up there :-)

Re line pressure: anyone have any data or guesses as to what's normal
pressure and if indeed a difference would be noted as tranny deteriorates or
has a foamy hissyfit?

Just wondering if it may seem feasable to monitor pressure along with
temperature where if abnormal pressures could be recognized it may save a
trip on a flatbed or at least it may give a guy the chance to get off the
road.

(Of course in my case from the other day I could've gotten off the road by
adding a quart or 2 of tranny fluid. However, had it run dry on the highway
adding fluid may not have done any good anyways, as in probably would've
been the final curtain call ;-)

Heinz

>
> > Investigation revealed that the fluid actually came out via the vent.
(No,
> > not overfilled).
> > Confirmed by simply running it for a bit and shutting it off.
> >
> > Dropped the pan and replaced the new Fram filter and O-ring with
another
> new
> > Fram filter and O-ring.
> >
> > Just came back from the test circuit and ALL SEEMS WELL.
> >
>
> Heinz,
> Verrrry interesting! My initial reaction is that this can only mean
that
> the transmission pump was sucking in air due to a displaced or damaged
> O-ring. The resulting foam caused the expulsion of ATF from the vent.
> The implications go beyond fluid loss and possible fire. If the tranny
is
> sucking air, one would likely have low line pressure. If the line
pressure
> is low, the transmission slips. Bingo! Burned clutches. This may
explain
> some of the mysterious (without warning) transmission failures we hear
about.
> Hmmmmmm....... Just something to triple check.
> I have always been concerned, as it is not common for an automatic
> transmission to blow fluid out its vent, nor for transmission clutches to
> burn out with little or no warning. You may have provided an explanation.
> Thanks.
>
> Rick Staples
> '75 Eleganza
> Louisville, CO
>
 
Heinz,
I don't know but I heard that the synthetic tranny fluids won't foam or at
least greatly reduce it. That in itself would have helped your problem. Is
the non foaming comment true or just another legend? Anybody know?
Bob McLaughlin

- -----Original Message-----
From: owner-gmcmotorhome
[mailto:owner-gmcmotorhome]On Behalf Of Heinz
Wittenbecher
Sent: Saturday, May 06, 2000 5:04 PM
To: gmcmotorhome
Subject: Re: GMC: Loosing Tranny fluid follow-up

Ventured out of the "circuit" today and still no panic overflow on landing.

Gonna assume all is back to normal and head over the Coqahalla next week. if
it ain't right it'll sure show up there :-)

Re line pressure: anyone have any data or guesses as to what's normal
pressure and if indeed a difference would be noted as tranny deteriorates or
has a foamy hissyfit?

Just wondering if it may seem feasable to monitor pressure along with
temperature where if abnormal pressures could be recognized it may save a
trip on a flatbed or at least it may give a guy the chance to get off the
road.

(Of course in my case from the other day I could've gotten off the road by
adding a quart or 2 of tranny fluid. However, had it run dry on the highway
adding fluid may not have done any good anyways, as in probably would've
been the final curtain call ;-)

Heinz

>
> > Investigation revealed that the fluid actually came out via the vent.
(No,
> > not overfilled).
> > Confirmed by simply running it for a bit and shutting it off.
> >
> > Dropped the pan and replaced the new Fram filter and O-ring with
another
> new
> > Fram filter and O-ring.
> >
> > Just came back from the test circuit and ALL SEEMS WELL.
> >
>
> Heinz,
> Verrrry interesting! My initial reaction is that this can only mean
that
> the transmission pump was sucking in air due to a displaced or damaged
> O-ring. The resulting foam caused the expulsion of ATF from the vent.
> The implications go beyond fluid loss and possible fire. If the tranny
is
> sucking air, one would likely have low line pressure. If the line
pressure
> is low, the transmission slips. Bingo! Burned clutches. This may
explain
> some of the mysterious (without warning) transmission failures we hear
about.
> Hmmmmmm....... Just something to triple check.
> I have always been concerned, as it is not common for an automatic
> transmission to blow fluid out its vent, nor for transmission clutches to
> burn out with little or no warning. You may have provided an explanation.
> Thanks.
>
> Rick Staples
> '75 Eleganza
> Louisville, CO
>
 
Don't know if myth or truth, but I'm running Synthetic :-)

Heinz

> Heinz,
> I don't know but I heard that the synthetic tranny fluids won't foam or at
> least greatly reduce it. That in itself would have helped your problem.
Is
> the non foaming comment true or just another legend? Anybody know?
> Bob McLaughlin
>
> -----Original Message-----
> From: owner-gmcmotorhome
> [mailto:owner-gmcmotorhome]On Behalf Of Heinz
> Wittenbecher
> Sent: Saturday, May 06, 2000 5:04 PM
> To: gmcmotorhome
> Subject: Re: GMC: Loosing Tranny fluid follow-up
>
>
> Ventured out of the "circuit" today and still no panic overflow on
landing.
>
> Gonna assume all is back to normal and head over the Coqahalla next week.
if
> it ain't right it'll sure show up there :-)
>
> Re line pressure: anyone have any data or guesses as to what's normal
> pressure and if indeed a difference would be noted as tranny deteriorates
or
> has a foamy hissyfit?
>
> Just wondering if it may seem feasable to monitor pressure along with
> temperature where if abnormal pressures could be recognized it may save a
> trip on a flatbed or at least it may give a guy the chance to get off the
> road.
>
> (Of course in my case from the other day I could've gotten off the road by
> adding a quart or 2 of tranny fluid. However, had it run dry on the
highway
> adding fluid may not have done any good anyways, as in probably would've
> been the final curtain call ;-)
>
> Heinz
>
>

> >
> > > Investigation revealed that the fluid actually came out via the vent.
> (No,
> > > not overfilled).
> > > Confirmed by simply running it for a bit and shutting it off.
> > >
> > > Dropped the pan and replaced the new Fram filter and O-ring with
> another
> > new
> > > Fram filter and O-ring.
> > >
> > > Just came back from the test circuit and ALL SEEMS WELL.
> > >
> >
> > Heinz,
> > Verrrry interesting! My initial reaction is that this can only mean
> that
> > the transmission pump was sucking in air due to a displaced or damaged
> > O-ring. The resulting foam caused the expulsion of ATF from the vent.
> > The implications go beyond fluid loss and possible fire. If the
tranny
> is
> > sucking air, one would likely have low line pressure. If the line
> pressure
> > is low, the transmission slips. Bingo! Burned clutches. This may
> explain
> > some of the mysterious (without warning) transmission failures we hear
> about.
> > Hmmmmmm....... Just something to triple check.
> > I have always been concerned, as it is not common for an automatic
> > transmission to blow fluid out its vent, nor for transmission clutches
to
> > burn out with little or no warning. You may have provided an
explanation.
> > Thanks.
> >
> > Rick Staples
> > '75 Eleganza
> > Louisville, CO
> >
>
>
 
I guess it is legend since it foams under the right(wrong?) circumstances.
Bob McL

- -----Original Message-----
From: owner-gmcmotorhome
[mailto:owner-gmcmotorhome]On Behalf Of Heinz
Wittenbecher
Sent: Saturday, May 06, 2000 11:35 PM
To: gmcmotorhome
Subject: Re: GMC: Loosing Tranny fluid follow-up

Don't know if myth or truth, but I'm running Synthetic :-)

Heinz

> Heinz,
> I don't know but I heard that the synthetic tranny fluids won't foam or at
> least greatly reduce it. That in itself would have helped your problem.
Is
> the non foaming comment true or just another legend? Anybody know?
> Bob McLaughlin
>
> -----Original Message-----
> From: owner-gmcmotorhome
> [mailto:owner-gmcmotorhome]On Behalf Of Heinz
> Wittenbecher
> Sent: Saturday, May 06, 2000 5:04 PM
> To: gmcmotorhome
> Subject: Re: GMC: Loosing Tranny fluid follow-up
>
>
> Ventured out of the "circuit" today and still no panic overflow on
landing.
>
> Gonna assume all is back to normal and head over the Coqahalla next week.
if
> it ain't right it'll sure show up there :-)
>
> Re line pressure: anyone have any data or guesses as to what's normal
> pressure and if indeed a difference would be noted as tranny deteriorates
or
> has a foamy hissyfit?
>
> Just wondering if it may seem feasable to monitor pressure along with
> temperature where if abnormal pressures could be recognized it may save a
> trip on a flatbed or at least it may give a guy the chance to get off the
> road.
>
> (Of course in my case from the other day I could've gotten off the road by
> adding a quart or 2 of tranny fluid. However, had it run dry on the
highway
> adding fluid may not have done any good anyways, as in probably would've
> been the final curtain call ;-)
>
> Heinz
>
>

> >
> > > Investigation revealed that the fluid actually came out via the vent.
> (No,
> > > not overfilled).
> > > Confirmed by simply running it for a bit and shutting it off.
> > >
> > > Dropped the pan and replaced the new Fram filter and O-ring with
> another
> > new
> > > Fram filter and O-ring.
> > >
> > > Just came back from the test circuit and ALL SEEMS WELL.
> > >
> >
> > Heinz,
> > Verrrry interesting! My initial reaction is that this can only mean
> that
> > the transmission pump was sucking in air due to a displaced or damaged
> > O-ring. The resulting foam caused the expulsion of ATF from the vent.
> > The implications go beyond fluid loss and possible fire. If the
tranny
> is
> > sucking air, one would likely have low line pressure. If the line
> pressure
> > is low, the transmission slips. Bingo! Burned clutches. This may
> explain
> > some of the mysterious (without warning) transmission failures we hear
> about.
> > Hmmmmmm....... Just something to triple check.
> > I have always been concerned, as it is not common for an automatic
> > transmission to blow fluid out its vent, nor for transmission clutches
to
> > burn out with little or no warning. You may have provided an
explanation.
> > Thanks.
> >
> > Rick Staples
> > '75 Eleganza
> > Louisville, CO
> >
>
>
 
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