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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

C4 leaks... inevitable?

  • Thread starter Thread starter SadbutTrue
  • Start date Start date May 22, 2007

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
May 22, 2007
#1
  • May 22, 2007
  • #1
My C4 has leaked... for as long as I can remember. Long ago I seem to remember seeing a post about how C4s pretty much... leak. But assuming that these leaks can in fact me eliminated, or minimized, it'd probably be a good idea to try.

Any common areas that are especially prone to leaking that I should be sure to check out when I get under the car tomorrow?

Thanks
 
R

rc4mike

Member
Oct 10, 2006
142
0
16
May 22, 2007
#2
  • May 22, 2007
  • #2
my father in law owned my car since 1970. He told me that my trans leaked for as long as he could remember. After i restored it, it still leaked. It was leaking from the bottom of filler tube as it fits in to the trans. After trying different o-rings, it still leaked. So then i decided to get a new filler tube. Guess what, no leaks! Turns out my father in law replaced the tube many years ago with the wrong tube.

No leaks after that...so far.

good luck
mike
 

whlnut_Ed

Founding Member
Apr 19, 2002
74
0
6
Brunswick, GA
May 22, 2007
#3
  • May 22, 2007
  • #3
Most leaks come from the thin trans pan that doesn't seal very well, and leaks worse when over-tightened.
Aftermarket aluminum pans have a thick rail that seals flat and won't distort. Trick Flow makes a good one.
 

65fastbackresto

Active Member
Apr 13, 2007
1,229
7
39
AR
May 22, 2007
#4
  • May 22, 2007
  • #4
Mine leaks

Drips off the shift linkage where it goes in the side of the tranny. Being as first gear is going out anyway, I`m tossing it soon.
 
P

palerider94

Member
Feb 21, 2006
573
1
19
May 22, 2007
#5
  • May 22, 2007
  • #5
Only leak left on my car is the Tranny - been fighting it for 2 years. So small now I decided to just live with - I do have a filer tube I need to put on yet. Has a hat instead of O ring - we'll see.
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
May 22, 2007
#6
  • May 22, 2007
  • #6
Anyone have a specific suggestion for a new filler tube? If they're reasonable I'll try that and a new pan/gasket. Thanks.
 
P

palerider94

Member
Feb 21, 2006
573
1
19
May 23, 2007
#7
  • May 23, 2007
  • #7
Got my pan and filler tube from below. Pan is nice and pretty reasonably priced. Have not mounted filler tube yet.


http://www.performanceautomatic.com/transc4.htm
 
6

65intex

New Member
Sep 16, 2006
85
0
0
Ft. Worth, Texas
May 23, 2007
#8
  • May 23, 2007
  • #8
My C4 leaks from the pan also. Tried different gaskets a couple of times but nothing seems to help. I have been thinnking of getting an aftermarket pan like some mentioned above. My car leaks bad and pretty much changes the fluid by itself over time.
 
P

palerider94

Member
Feb 21, 2006
573
1
19
May 23, 2007
#9
  • May 23, 2007
  • #9
Mine leaked at the pan - even with new aluminum pan. Ended up putting gasket selaer (Right Stuff) lihglty on each side. Pan is fine now but got a small leak I think near filler tube - hard to trace but coming from up top - could be vent also.
 

krash kendall

Active Member
Nov 19, 2004
1,258
0
36
Aldergrove, B.C. Canada
May 23, 2007
#10
  • May 23, 2007
  • #10
My C4 never leaks. I RTV'd the battered up pan after the gasket failed. New yoke seal as well.
 
6

66bluepony

New Member
Nov 7, 2004
75
1
0
May 23, 2007
#11
  • May 23, 2007
  • #11
C4 Leaks

C4's almost never leak from the pan. Almost all leaks are above the pan, runs down and looks like pan leak. C4's are as leak free as any auto. Places to check, dipstick (2 types of seal & are not interchangeable, servo cover, band adjusting screw, (use new nut every time when adjusting, nut has seal) vent, front & rear seal. Also modulator can leak and the vaccum line sucks the oil to the engine burning it.
 
M

mustangdave

My rearend needs a stud and two nuts.
Founding Member
Feb 26, 2002
2,976
1
56
North Carolina
May 23, 2007
#12
  • May 23, 2007
  • #12
Everyone has mentioned the common leak spots so I'll do a litlle hijacking. 66bluepony mentioned the vent and I was wondering if anybody has tried putting a very small filter there to absorb fluids? I know this is a very small issue but I'm feeling anal retentive this evening.
 
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