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C4 leaking.. opinions? (pics inside)

  • Thread starter Thread starter kslushy
  • Start date Start date Dec 17, 2003

kslushy

Founding Member
Jan 25, 2002
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37
Dec 17, 2003
#1
  • Dec 17, 2003
  • #1
Thanks in advance for any help anyone can offer. My original c4 was rebuilt about 2-3 years ago, and has since seen about 1000 miles total. This past summer it had a problem about leaking a LOT of fluid out of it when parked. As soon as i brought it back in the garage from driving it, no leaks. In the morning there would be a gigantic puddle of ATF on the ground. So I replaced the pan gasket and at the same time the filter, and also had a drain plug welded onto the pan. Same problem happens. I go under the car today to tighten up the pan bolts and see if I could determine where it was leaking from, looks clean almost everywhere. the only evidence of leaking ATF was on the pan bolts. Is it still leaking from the pan?

Is there a different gasket I should use or put some RTV around the bolt holes?

Looks like its leaking from the back of the trans. Pics are of the pass and drivers rear corners.
 

kslushy

Founding Member
Jan 25, 2002
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37
Dec 17, 2003
#2
  • Dec 17, 2003
  • #2
.

 

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joemamma

New Member
Dec 10, 2003
14
0
0
Dec 18, 2003
#3
  • Dec 18, 2003
  • #3
Check the dipstick tube. It uses either o-rings or a rubber bootie, depending on where it enters. When you stop the engine, half the converter empties into the pan, filling up the tube. If your o-ring/boot is leaking, you gotta flood.
 

TazerRE

Founding Member
May 8, 2002
328
0
0
Bellingham, WA
Dec 18, 2003
#4
  • Dec 18, 2003
  • #4
I know you said it's on the bolts, or leaking from the back, but I'm gonna have to use a "what he said" on this one. Read above.
 
R

restomod

Founding Member
Feb 28, 2000
1,480
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0
Longview ,Texas
Dec 18, 2003
#5
  • Dec 18, 2003
  • #5
the modulator valve should have a gasket under it. if there is not one it will leak. just another place to check if you your dipstick is fine.
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Dec 18, 2003
#6
  • Dec 18, 2003
  • #6
If you over tork the bolts, you bend the panholes.
this will tend to wave the pan between holes and it will seep fluid.
next time you have the pan off, Check around the holes.

If their pushed inward, Use the round end of a ball peen hammer to
drive them back.
The gasket is there to seal not squeeze out, too much tork there
PB
 

kslushy

Founding Member
Jan 25, 2002
1,125
0
37
Dec 18, 2003
#7
  • Dec 18, 2003
  • #7
Thanks everyone, i'll check tomorrow.

I'm aware of the torque on the pan bolts, I usually put them to a little more than snug. I'll take the pan off tomorrow to check for waves in case however... thanks!
 

allcarfan

The Answer Man
Founding Member
Apr 8, 2001
2,458
1
56
North Atlanta
Dec 18, 2003
#8
  • Dec 18, 2003
  • #8
Kslushy,

I had this EXACT same problem in my c4...and it only had 4700 miles on it. It wouldnt leak at all driving, as soon as it was parked...drip...drip...drip....

I removed the trans recently and everything looked ok. I had fluid on my pan bolts...couldnt figure out where it was coming from.....

I take the dipstick tube out....the oring was broke at the bottom...looked like someone had bitten it (I dont think it was me). That was the culprit.

Be forwarned...when you remove your dipstick tube....LOTS OF FLUID COMES OUT. I learned that the hard way last weekend
 

kslushy

Founding Member
Jan 25, 2002
1,125
0
37
Dec 18, 2003
#9
  • Dec 18, 2003
  • #9
thanks allcarfan!

I also gt the atf bath this summer when i changed out the pan gasket...thinking it was empty! the pan has a drain plug on it now though
 
7

7DMACH1

Founding Member
Jan 5, 2002
1,087
0
37
Lansdale PA.
Dec 18, 2003
#10
  • Dec 18, 2003
  • #10
Check the lever seals on the l/s of the trans. Fluid runs down so it could be leaking up higher and makes it look as if it's the pan. RAY
 
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