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

C4 leaking- Help Please!

  • Thread starter Thread starter JeffM
  • Start date Start date Jul 8, 2009
J

JeffM

New Member
Jul 8, 2009
4
0
0
Jul 8, 2009
#1
  • Jul 8, 2009
  • #1
Hi, new here and enjoy reading the posts. My issue is that I am about complete in finishing my '65 conv and I have to keep topping it off with type FA fluid. Rebuilt C4, put new front seal in and I keep getting a decent puddle after I shut it off for a few days. I added about a qt just to take it up to get painted. I stopped in the next day at the paint shop and it looks to have lost quite a bit. Anyways, any suggestions short of pulling the tranny down? It only drips when I have to add that final qt. I have to in order to drive it and I am not over filling, between the marks. I tried a new pan gasket, to no avail. Seems as if when the converter is draining back, it leaks out somewhere. Very hard to pinpoint. Any suggestions would be appreciated! Jeff
 

dcstang67

Member
May 26, 2008
127
1
19
Jul 8, 2009
#2
  • Jul 8, 2009
  • #2
Are you checking the fluid with the engine running and in neutral?
 
J

JeffM

New Member
Jul 8, 2009
4
0
0
Jul 8, 2009
#3
  • Jul 8, 2009
  • #3
Yes, I check with it warmed up and in park. Fluid not coming out from the overflow tube either.
 

golf4283

Active Member
May 30, 2003
1,253
1
39
Orland Park, Illinois
Jul 8, 2009
#4
  • Jul 8, 2009
  • #4
Granted I haven't run a C4 in a while but maybe run it around and let it sit and see how much fluid comes out. Then run it again for a bit without filling it back up and park it again. If no more fluid comes out then it was indeed overfilled. If more comes out then you have another set of problems.

Driving it with low fluid won't kill it as long as you're taking it easy and just warming it up. My T-5 leaks a little bit off the bat cause I overfilled I'm sure but not a drop has come out since then.
 

dcstang67

Member
May 26, 2008
127
1
19
Jul 8, 2009
#5
  • Jul 8, 2009
  • #5
This may sound crazy, but how do you know you have the right dipstick?
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Jul 8, 2009
#6
  • Jul 8, 2009
  • #6
And it is all the way down.
 

HookandLadder

Founding Member
Feb 17, 2001
261
0
17
St Louis
Jul 8, 2009
#7
  • Jul 8, 2009
  • #7
Take off the access cover on the bottom of the trans. Check the converter and make sure the drain plug is A. There B. tight . You may have to roll the converter through a revolution in neutral to see the plug in the converter. I believe it is on the front side............DAVE?
 

dcstang67

Member
May 26, 2008
127
1
19
Jul 9, 2009
#8
  • Jul 9, 2009
  • #8
depending on the converter you may have a plug and you may not. If you do you should see it through a hole in the flywheel at the front of the converter.
 
J

JeffM

New Member
Jul 8, 2009
4
0
0
Jul 9, 2009
#9
  • Jul 9, 2009
  • #9
I am pretty sure the plug is tight. It will be at the paint shop for about another 5-7 days. Man, it is driving me nuts walking out into an empty garage when I want to tinker.. I am going to check on it today and see if it is still leaking bad. I am leaning towards a dipstick tube leak(even though I siliconed it). Atleast I am hoping that.
 
J

JeffM

New Member
Jul 8, 2009
4
0
0
Jul 10, 2009
#10
  • Jul 10, 2009
  • #10
Went up to the paint shop and measured the dipstick. It measures approx 20 1/2". That is the length of the inside, where it goes into tube, not overall length. This one has sort of like a 4-wire type configuration just below the cap, not the typical squiggly spring steel as seen on most. I am pretty sure it is correct, but not positive. I am going to get a correct o-ring and hopfully that is the culprit. Hopefully, the car will be back here soon.
 
You must log in or register to reply here.

Similar threads

C
C4 trans help needed
  • CPH89LX
  • Apr 26, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
6
Views
224
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Apr 28, 2026
CPH89LX
C
P
Engine Mysterious coolant leak at back of engine
  • palerider94
  • Jan 18, 2026
  • Fox 5.0 Mustang Tech
Replies
1
Views
196
Fox 5.0 Mustang Tech Jan 19, 2026
AeroCoupe
N
Edelbrock 1405 Setup
  • nathantaylor200
  • Nov 4, 2025
  • Classic Mustang Specific Tech
Replies
3
Views
248
Classic Mustang Specific Tech Nov 5, 2025
nathantaylor200
N
R
1965 C4 Tranny leaking?
  • Rick1965Coupe
  • Jul 28, 2024
  • Classic Mustang Specific Tech
Replies
6
Views
790
Classic Mustang Specific Tech Aug 7, 2024
Rick1965Coupe
R
Drivetrain 83’ Glx convertible C5 Trans help!
  • JacksonJared2113
  • Dec 25, 2025
  • Fox 5.0 Mustang Tech
Replies
2
Views
401
Fox 5.0 Mustang Tech Dec 26, 2025
JacksonJared2113
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?