Spitting Transmission

Carl Stouffer

Carl Stouffer

Well-known member
Jan 15, 2009
4,688
380
83
Tucson, Arizona 85718
After not having any issues with the new transmission for the first 5,000 miles, it has taken to spitting some fluid out of the vent (yes, I have an
elbow on it with a hose to the outside of the framein place of the vent cap) It lost close to a quart on the trip to Big Bend (1333 miles).

Is this a symptom of a partially plugged filter? I am planning to service it anyway, and probably should have done a first fluid change sooner than
at 7500 miles.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
Just guessing but something is introducing air bubbles raising fluid level. Could be filter seal or I have heard pump whine on a TH 700 series with
clogged filter. But that was on 130K mile car. There should not be much friction material in the fluid on such a new build.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
That is a real bummer.

I cant imagine a clogged filter in your case. I would wonder about 2 things 1st.

1st is fluid level.

2nd is somehow your vent system or something in the engine compartment is causing some vacuum or airflow that is "sucking" some fluid out the vent.

Talk to ray E. He fought this for a while. Ended up being internal on his tranny. But hopefully that is not your case(his was not recently
rebuilt).
--
Jon Roche
75 palm beach
EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
I just drained it and dropped the pan this afternoon. The fluid looked like new coming out and there was not any excessive clutch material in the
pan. I'm thinking maybe the new clutches etc may have lost a bit more material on 'break-in' than they would have regularly. I am (of course) going
to replace the filter, with new O-rings and be careful with the fluid level. One of the two O-rings on the filter had a little kink in it, so it
might have been sucking a little air.

I am running Mobil-1 full synthetic fluid in the transmission. I'm pretty sure everything is Okay with it. I think I'll put a catch can on the vent
hose so I can monitor the situation better.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
If the pan is still off calibrate the dipstick, there's significant variati=
ons in them.1. Put a straight edge across the bottom of the transmission ca=
se where the pan bolts on.2. Make sure the dipstick is all the way in.3. Pu=
t a temporary mark on the dipstick where it hits the straight edge.4.=C2=
=A0 Measure down 1/4" on the dipstick and put a permanent mark.=C2=A0 That =
is the correct HOT/FULL mark.Sent from my U.S.Cellular=C2=A9 Smartphone =
-------- Original message --------From: Carl Stouffer via Gmclist Date: 2/15/20 9:55 PM (GMT-06:00) To: gmclist=
t.org Cc: Carl Stouffer Subject: Re: [GMCnet] Spitting=
Transmission I just drained it and dropped the pan this afternoon.=C2=
=A0 The fluid looked like new coming out and there was not any excessive cl=
utch material in thepan.=C2=A0 I'm thinking maybe the new clutches etc may =
have lost a bit more material on 'break-in' than they would have regularly.=
=C2=A0 I am (of course) goingto replace the filter, with new O-rings and be=
careful with the fluid level.=C2=A0 One of the two O-rings on the filter h=
ad a little kink in it, so itmight have been sucking a little air. I am run=
ning Mobil-1 full synthetic fluid in the transmission.=C2=A0 I'm pretty sur=
e everything is Okay with it.=C2=A0 I think I'll put a catch can on the ven=
those so I can monitor the situation better.-- Carl Stouffer'75 ex Palm Bea=
chTucson, AZ.Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD fi=
nal drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear Ame=
rican Eagles,Solar battery charging.=C2=A0 GMCSJ and GMCMI member__________=
_____________________________________GMCnet mailing listUnsubscribe or Chan=
ge List Options:http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet=
.org
 
If the pan is still off calibrate the dipstick, there's significant variations in them.

1. Put a straight edge across the bottom of the transmission case where the pan bolts on.

2. Make sure the dipstick is all the way in.

3. Put a temporary mark on the dipstick where it hits the straight edge.

4.  Measure down 1/4" on the dipstick and put a permanent mark.  That is the correct HOT/FULL mark.

--
Ray Erspamer
78 GMC Royale
414-484-9431
 
My transmission was blowing fluid out of the dipstick tube. 1 gallon in 100 miles. Transmission had an internal pressure leak, after a complete
rebuild all is good.
--
Ray Erspamer
78 GMC Royale
414-484-9431
 
This is a much smaller issue than that. It blew , maybe, a pint out in 500 miles. It just may have been overfilled. I read the post about
calibration too late to do it this time, but I don't think there a significant problem (Crossing my fingers).

It's all back together.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
Update on this:

I serviced the transmission, changed the fluid (Mobil-1 Full Synthetic) and filter (ATP) and added a small catch can to the vent hose.

Last weekend, the GMCSJ had a small rally at a local casino about 25 miles from our home and there was no indication of any transmission fluid
spitting out of the vent. Maybe 25 miles (each way with 10 miles on the freeway) was not enough of a test to see if everything is okay, but I'm
hoping so. Still don't know why it did it. Maybe I overfilled it the last time I checked the level.

I guess the real test will be our next multi hundred mile trip in early April.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
The old filter O-Ring may have been leaking.=C2=A0 A new filter and O-Rings=
may have solved the problem=C2=A0Sent from my U.S.Cellular=C2=A9 Smartpho=
ne -------- Original message --------From: Carl Stouffer via Gmclist Date: 3/9/20 1:44 PM (GMT-06:00) To: gmclist=
mcnet.org Cc: Carl Stouffer Subject: Re: [GMCnet] Spit=
ting Transmission Update on this:I serviced the transmission, changed the f=
luid (Mobil-1 Full Synthetic) and filter (ATP) and added a small catch can =
to the vent hose.Last weekend, the GMCSJ had a small rally at a local casin=
o about 25 miles from our home and there was no indication of any transmiss=
ion fluidspitting out of the vent.=C2=A0 Maybe 25 miles (each way with 10 m=
iles on the freeway) was not enough of a test to see if everything is okay,=
but I'mhoping so.=C2=A0 Still don't know why it did it.=C2=A0 Maybe I over=
filled it the last time I checked the level.I guess the real test will be o=
ur next multi hundred mile trip in early April.-- Carl Stouffer'75 ex Palm =
BeachTucson, AZ.Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD=
final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear =
American Eagles,Solar battery charging.=C2=A0 GMCSJ and GMCMI member_______=
________________________________________GMCnet mailing listUnsubscribe or C=
hange List Options:http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmc=
net.org
 
FYI, Do some research relative to the Trans filters. Some of the off shore filters have come with filter necks of the wrong size. The part that fits
up into the transmission has been to small so does not fit as a "friction fit" with the "O" ring. Fits so loose that with the "O" ring, it can drop
out on it's own, so loose that air can get past. Measure the diameter of the pipe going into the transmission, and it should be of a certain size.
Maybe someone here knows what that measurement is. So when you buy a filter, you need to measure the diameter before you pay for it and walk out of
the store.

Just did a quick search on this GMCforum and found this...."Double check the filter neck to make sure it's 0.75" wide, if it's too
small it can fall out. You can also add an additional o-ring to help it out.

--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Thanks Larry,

Yes I am aware of the transmission filter issue. I measured the neck on the new ATP filter and it was right at .75 inches. I also routinely install
two O-rings on those, so did the transmission builder. One of the two that he installed had a little bit of a kink in it. I think that was where the
original problem came from. Perhaps it was sucking a tiny bit of air and causing the fluid to foam a little.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
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