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2004 Mustang 3.9L V6 Leaking Fluid or Oil

  • Thread starter Thread starter ROBERTOS2004Mustang
  • Start date Start date Aug 31, 2020
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    2004 mustang 3.9l v6
R

ROBERTOS2004Mustang

New Member
Aug 31, 2020
15
0
1
Los Angeles, California
Aug 31, 2020
#1
  • Aug 31, 2020
  • #1
Good morning everyone,

I'm new to StangNet.com, but I've been a Mustang owner since my 1991 Ford Mustang LX 2.3L. I'm trying to fix a fluid or oil leak on my current Mustang.

My car = 2004 Ford Mustang 3.9L V6 Automatic Transmission with 144K miles.

Background = I bought this car brand new from the dealer back in 2004 and have always maintained the car using full synthetic motor oil and other maintenance on time. In 2017 I needed money so I was going to sell my car to someone, but my dad said he'd buy it. Flash forward to today and my dad was going to sell the car to someone, but I told him I'd buy it. He has not really used the car since Summer 2019. He would just move it once a week from one side of the street to the other to avoid the street sweeper (ticket). He then started having problems with the alarm, check engine, fuel cap, battery every week even after getting a new battery. I bought it and took the problem off his hands since I knew the car.

I put a brand new battery, negative battery terminal (post), but now I noticed a fluid or oil leak. I took several pictures from underneath the car so you can see where the leak may be coming from. I'm not too familiar with fluid or oil leaks and was hoping someone here can help me determine where the leak is coming from and how to fix it.

Thank you all for your support and I hope together we can solve this.
 

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ROBERTOS2004Mustang

New Member
Aug 31, 2020
15
0
1
Los Angeles, California
Sep 5, 2020
#2
  • Sep 5, 2020
  • #2
UPDATE:
I have checked both the oil dipstick and transmission fluid dipstick and have noticed something. The motor oil dipstick is at its normal level, but the transmission fluid dipstick isn't. The dipstick has two (2) sides to it; one cold and one hot. I checked the level while it was cold and it was good (the whole level had fluid), but when I checked the level after driving for about an hour nonstop the hot level was halfway (exactly at the H on the dipstick). Don't know if this is normal or signs of a transmission fluid leak. Also, I did some research online and in between the motor oil pan/drain and the transmission pan is the torque converter. I think, but I'm not sure if the Torque Converter Shaft Seal is leaking. Or at least that's what I could come up with. I have also uploaded two (2) new pictures showing the leak droplets. I put a cardboard with a gray paper and one photo is with flash while the other is without flash. I never changed the automatic transmission fluid while I was the owner, but would check the levels through the dipstick every 5,000 miles and remember it being filled on the whole level grooves on the dipstick for both hot and cold. I asked my dad and he never checked. Kindly post your thoughts or ideas. Thank you all for your ideas, comments and posts.
 

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ROBERTOS2004Mustang

New Member
Aug 31, 2020
15
0
1
Los Angeles, California
Oct 12, 2020
#3
  • Oct 12, 2020
  • #3
UPDATE:
I have continued to check the transmission fluid through the dipstick once a week (every 7 days) and the level has stayed at the "H" on the dipstick. I check it every time while the car is running. It drops one (1) or two (2) drops everyday, so I will probably just wait until it's time for the transmission fluid and filter change at 150K miles. Currently I'm at 144K miles, but I will continue to monitor the levels of both the motor oil and transmission fluid to be safe.
 
L

Laupro

New Member
Jan 9, 2022
5
2
1
Sacramento, CA
Jan 9, 2022
#4
  • Jan 9, 2022
  • #4
ROBERTOS2004Mustang said:
Good morning everyone,

I'm new to StangNet.com, but I've been a Mustang owner since my 1991 Ford Mustang LX 2.3L. I'm trying to fix a fluid or oil leak on my current Mustang.

My car = 2004 Ford Mustang 3.9L V6 Automatic Transmission with 144K miles.

Background = I bought this car brand new from the dealer back in 2004 and have always maintained the car using full synthetic motor oil and other maintenance on time. In 2017 I needed money so I was going to sell my car to someone, but my dad said he'd buy it. Flash forward to today and my dad was going to sell the car to someone, but I told him I'd buy it. He has not really used the car since Summer 2019. He would just move it once a week from one side of the street to the other to avoid the street sweeper (ticket). He then started having problems with the alarm, check engine, fuel cap, battery every week even after getting a new battery. I bought it and took the problem off his hands since I knew the car.

I put a brand new battery, negative battery terminal (post), but now I noticed a fluid or oil leak. I took several pictures from underneath the car so you can see where the leak may be coming from. I'm not too familiar with fluid or oil leaks and was hoping someone here can help me determine where the leak is coming from and how to fix it.

Thank you all for your support and I hope together we can solve this.
Click to expand...
Hey I'm having a similar leak with my same model mustang. Did you find out what was wrong with it? I'm at 120,000 miles.
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
1,463
223
Sea of Tranquility
Jan 9, 2022
#5
  • Jan 9, 2022
  • #5
The rear main seal is known to leak. Especially if the car sits for awhile.
 
Reactions: Laupro
L

Laupro

New Member
Jan 9, 2022
5
2
1
Sacramento, CA
Jan 10, 2022
#6
  • Jan 10, 2022
  • #6
COramprat said:
The rear main seal is known to leak. Especially if the car sits for awhile.
Click to expand...
Good to know. I was out of the country for two years and the car mostly sat.
 
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