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Transmission oil spewing from tube

  • Thread starter Thread starter KramNation
  • Start date Start date May 2, 2005
K

KramNation

New Member
May 2, 2005
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May 2, 2005
#1
  • May 2, 2005
  • #1
Hello all,

I have a 66 mustang 289, with a C4 automatic transmission. For some reason when we stop the engine, oil will come out of the dip stick tube.
Has anyone heard of this?
What could could cause this back pressure?

A transmisson placed siad it must be over filled, but when I check the oil with engine off, it goes over the fill mark. When I check the oil during idle I can be as low as barley showing on the stick. What this proves to me is that it is not over filled IMO.

Any help will be welcomed.
 

stangman67

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Feb 8, 2003
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connecticut
May 2, 2005
#2
  • May 2, 2005
  • #2
Hmm, idling in park should put it in the hatched mark, meaning its filled to the correct level. Are you driving it normally when its finally parked, or beating on it. Possibly the convertor is having a problem, like slipping, and super-heating the oil, like a stall convertor may do. Hows the radiator cooler?
 
M

my66coupe

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Apr 30, 2002
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Arizona fountain hills
May 2, 2005
#3
  • May 2, 2005
  • #3
When ATF heats up, it expands greatly, For your transmission to overflow out the dipstick may indicate an overheating issue. When this happens, get under the car and listen for the tranny fluid boiling (like boiling water). Does the car shift weird or have any other problems with the tranny?

Mike
 
G

Gud T.B. Blown

Member
Dec 9, 2004
583
1
18
May 3, 2005
#4
  • May 3, 2005
  • #4
my newer car just did this 2 weeks ago and it was caused by a blocked vent tube, tranny fluid overflowed like crazy. i'm not familiar whether the C4 has any venting or not. something to check.
 
6

66HertzClone

New Member
Aug 24, 2004
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Central New Jersey
May 3, 2005
#5
  • May 3, 2005
  • #5
C4 transmissions due indeed have a vent. It is located on the driver side near the reverse servo cover. Mine was a bent piece of 5/16 steel tubing, shaped like a question mark. Make sure dirt has not accumulated around the open end.

Saw this problem once on a Chevy Silverado, I flipped the locking lever on the end of the trans dipstick and as I pulled it out, hot trans fluid shot out like a fire-hose. All over my face and shirt, thank god I was wearing safety glasses.
 
K

KramNation

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May 2, 2005
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May 3, 2005
#6
  • May 3, 2005
  • #6
Thanks all for the info.

I don't think it is over heating, because it will do it even if it was only running from a cold start then killed.

I went to look at the vewnt tube, but I can not find one. On the right side I have the tube that runs to the manifold, which is vacuum I think. Where is the reverse servo cover? I have looked in my chilton, or hayes manual and they show nothing for vent tube, or reverse servo cover.
 

84convertablegt

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Nov 6, 2004
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Columbus, OH
May 3, 2005
#7
  • May 3, 2005
  • #7
the vent is on the drivers side on the top kinda of the tranny. i found mine when i overfilled the tranny with fluid. it sounded like a huge fart as it poured on out of there.
 
M

mustangprodude

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Jun 7, 2004
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May 4, 2005
#8
  • May 4, 2005
  • #8
I have a '73 C4 that came out of a Maverick and it's vent is on top the tranny. It's like a little cap that's spring loaded. Not sure when Ford started doing that.
 
M

MitchGT

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Apr 1, 2005
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May 4, 2005
#9
  • May 4, 2005
  • #9
did it just start doing this, or was the tranny out of the car for repair or something? Air expands even more than tranny fluid,so if there was alot of air in the torque converter (ie; it wasn't filled seperately from the tranny when assembled) it might expand and push out the fluid. I don't think air would get into a tranny that was already working ok though.
 
K

KramNation

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May 2, 2005
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May 4, 2005
#10
  • May 4, 2005
  • #10
MitchGT said:
did it just start doing this, or was the tranny out of the car for repair or something? Air expands even more than tranny fluid,so if there was alot of air in the torque converter (ie; it wasn't filled seperately from the tranny when assembled) it might expand and push out the fluid. I don't think air would get into a tranny that was already working ok though.
Click to expand...

Hmmm... That could be the problem. I pulled the engine along with torque converter. Some oil di go out during this process, but I thought the oil from the tranny would supply the correct amount back to the torque converter. Doh!
So if the vent does not work then thats my next area to look at.. I guess the tranny has to drops to fill the torque converter, is this so?
 
F

ForceFed70

That's why they call it "dope"
Founding Member
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May 4, 2005
#11
  • May 4, 2005
  • #11
It's not air in the TC. I've installed more than a couple of dry TC's and I've never seen this problem. Plus the TC needs to be filled with fluid before the car will even move. His car drives..which means there is none (or very little) air in the TC.
 

shotsy

New Member
Apr 8, 2005
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Oklahoma City
May 4, 2005
#12
  • May 4, 2005
  • #12
70_Nitrous_Eater said:
It's not air in the TC. I've installed more than a couple of dry TC's and I've never seen this problem. Plus the TC needs to be filled with fluid before the car will even move. His car drives..which means there is none (or very little) air in the TC.
Click to expand...


Not to steal the thread but I just realized that I put my converter in this past saterday and forgot to add fluid to it before I dropped it into the car. Can I add fliud to the trans while the car is running and fill the converter? Hoping to start her for the first time this weekend..... Just finishing up the duraspark mod and the 12si (GM) alternator conversion.


Motor tranny & Headers go in
 

84convertablegt

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Nov 6, 2004
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Columbus, OH
May 5, 2005
#13
  • May 5, 2005
  • #13
shotsy said:
Not to steal the thread but I just realized that I put my converter in this past saterday and forgot to add fluid to it before I dropped it into the car. Can I add fliud to the trans while the car is running and fill the converter? Hoping to start her for the first time this weekend..... Just finishing up the duraspark mod and the 12si (GM) alternator conversion.


Motor tranny & Headers go in
Click to expand...
its better to add a quart or 2 before your install it onto the pump shaft but it will fill up when you start it, it just wont do anything until it fills up. its not the best thing for the converter, but it will fill up
 
K

KramNation

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  • May 5, 2005
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84convertablegt said:
its better to add a quart or 2 before your install it onto the pump shaft but it will fill up when you start it, it just wont do anything until it fills up. its not the best thing for the converter, but it will fill up
Click to expand...
It's not air in the TC. I've installed more than a couple of dry TC's and I've never seen this problem. Plus the TC needs to be filled with fluid before the car will even move. His car drives..which means there is none (or very little) air in the TC.
Click to expand...
What a relief, I hated the thought of having to pull the tranny out. The TC did have some oil when I installed the engine, but I didn't replace the oil that spilled out.
I will locate that vent this week-end and see if it is plugged.
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
4,818
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BC Canada
May 5, 2005
#15
  • May 5, 2005
  • #15
84convertablegt said:
its better to add a quart or 2 before your install it onto the pump shaft but it will fill up when you start it, it just wont do anything until it fills up. its not the best thing for the converter, but it will fill up
Click to expand...

I agree.. you should be fine.

Just start her up and keep it in neutral for a minute or 2 before trying to drive it anywhere.
 

thehueypilot

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Feb 25, 2004
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May 5, 2005
#16
  • May 5, 2005
  • #16
I had a C4 that did this at 6k rpm and the transmission was fine. I believe someone invented a locking dip stick to cure this issue. Once I installed it the fluid could not force the dip stick out of the tube and no more mess was the result. I have one on my AOD as well.
 
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