• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Explorer ST Forum and Explorer ST community dedicated to Explorer ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Explorer ST Forum today!


Leaking transmission

jwuonog

jwuonog

Member
#1
Messages
221
Reactions
89
Points
27
Location
Jessup, MD, USA
#1
I recently found that I have a very small and slow leak in my transmission. I noticed some red fluid on the heat shield every time I drove. It would especially pool towards the rear of the transmission, sometimes even dripping slightly off of the back portion of the pan.

20240421_082523.jpg

I removed the heat shield and cleaned the area thoroughly and drove some more, I believe it is actually coming from the front right section of the transmission. I found fluid above where the plastic pan meets the transmission, so I don't think it's the pan gasket.

Any idea what it could be? I know there's a vent in that area. My next possible suspect is the input shaft seal is leaking on that side.

Has anyone ever experienced this leak?
 

GearHead_1

GearHead_1

1000 Post Club
#2
Messages
1,557
Reactions
1,301
Points
262
Location
Utah
Vehicle
Exploder
#2
Trans cooler? These have been known to leak.
 

OP
jwuonog

jwuonog

Member
Thread Starter #3
Messages
221
Reactions
89
Points
27
Location
Jessup, MD, USA
Thread Starter #3
GearHead_1 said:
Trans cooler? These have been known to leak.
Click to expand...
I wish it was that, it would be an easy fix.

I looked on the driver's side and the cooler area, it looked pretty good.
 

OP
jwuonog

jwuonog

Member
Thread Starter #4
Messages
221
Reactions
89
Points
27
Location
Jessup, MD, USA
Thread Starter #4
Here's the passenger front corner. When I put a dry paper towel in that area above the pan, it came back with red fluid on it.

20240507_011156.jpg

Cooler lines seem ok.
20240507_011156.jpg
 

Attachments

MKdude

MKdude

Member
#5
Messages
59
Reactions
16
Points
7
Location
Cape Girardeau MO
Vehicle
2020 Ford Explorer ST
#5
im experiencing a leak with a hose by the transmission it has a white plastic plug and is slowly leaking
 

OP
jwuonog

jwuonog

Member
Thread Starter #6
Messages
221
Reactions
89
Points
27
Location
Jessup, MD, USA
Thread Starter #6
Had an appointment with the dealer today, but their transmission guy is booked until June.

Apparently this car has had some leaks at the output shaft seal and some harsh shift issues in 2021. The trans has definitely been out of the car at some point, possibly rebuilt.
 

hbalek

hbalek

Active Member
#7
Messages
950
Reactions
530
Points
232
Location
Kensington, MD, USA
#7
jwuonog said:
Had an appointment with the dealer today, but their transmission guy is booked until June.

Apparently this car has had some leaks at the output shaft seal and some harsh shift issues in 2021. The trans has definitely been out of the car at some point, possibly rebuilt.
Click to expand...
jwuonog said:
Had an appointment with the dealer today, but their transmission guy is booked until June.

Apparently this car has had some leaks at the output shaft seal and some harsh shift issues in 2021. The trans has definitely been out of the car at some point, possibly rebuilt.
Click to expand...
Mine was rebuilt at 25K miles and now I'm at 50K miles. There's a TSB for the 6-7 gear shift problem and A Clutch and clamp replacement.
 

OP
jwuonog

jwuonog

Member
Thread Starter #8
Messages
221
Reactions
89
Points
27
Location
Jessup, MD, USA
Thread Starter #8
I don't want to speak to soon, but my leak seems to have gone away on its own. I'm quite confused by it, but I'm not complaining.

I did do a trans filter and 5 qts of Mercon ULV back in November and reused the pan gasket. I noticed the leak in late April, who knows if it was leaking the whole time.

I ordered a new pan gasket and more fluid recently, just in case it was my error or a bad gasket. It still had a tiny drip, which led to this post. I vacuum suctioned the fluid out before dropping the pan. I got about 4 quarts out, and didn't change the filter this time.

My theory is that maybe it was leaking since November due to bad gasket or improper installation, and I was seeing residual fluid after.
 

MKdude

MKdude

Member
#9
Messages
59
Reactions
16
Points
7
Location
Cape Girardeau MO
Vehicle
2020 Ford Explorer ST
#9
My leak comes from the trannie cooler and it magically stopped yesterday as well. im still getting it in to the dealer
 

OP
jwuonog

jwuonog

Member
Thread Starter #10
Messages
221
Reactions
89
Points
27
Location
Jessup, MD, USA
Thread Starter #10
1731047061992.png

I noticed a while ago that there was some old fluid in the circled area.

I don't believe it has gotten any worse, several months later. Any indication of what kind of fluid that may have been? I know the owner before me had some transmission issues in the past.
 

C

Cdubya

1000 Post Club
#11
Messages
1,693
Reactions
842
Points
262
Location
NE Ohio
Vehicle
2020 Explorer ST
#11
jwuonog said:
View attachment 26221

I noticed a while ago that there was some old fluid in the circled area.

I don't believe it has gotten any worse, several months later. Any indication of what kind of fluid that may have been? I know the owner before me had some transmission issues in the past.
Click to expand...
You better check for FADA oil leak. Remove that center rectangular undershield. It'll be on the driver's side. Do not ignore an oil leak!
 

OP
jwuonog

jwuonog

Member
Thread Starter #12
Messages
221
Reactions
89
Points
27
Location
Jessup, MD, USA
Thread Starter #12
Cdubya said:
You better check for FADA oil leak. Remove that center rectangular undershield. It'll be on the driver's side. Do not ignore an oil leak!
Click to expand...
I had the FADA leak done earlier this year. Could it be oil from that?
 

23 Explorer ST

23 Explorer ST

Member
Firefighter/EMT
#13
Messages
280
Reactions
157
Points
37
Location
NC
Vehicle
2023 Ford Explorer ST
#13
jwuonog said:
View attachment 26221

I noticed a while ago that there was some old fluid in the circled area.

I don't believe it has gotten any worse, several months later. Any indication of what kind of fluid that may have been? I know the owner before me had some transmission issues in the past.
Click to expand...
Rear main seal possibly? Hard to tell by the pic.


Sent from my iPhone using Tapatalk
 

OP
jwuonog

jwuonog

Member
Thread Starter #14
Messages
221
Reactions
89
Points
27
Location
Jessup, MD, USA
Thread Starter #14
23 Explorer ST said:
Rear main seal possibly? Hard to tell by the pic.


Sent from my iPhone using Tapatalk
Click to expand...
That is my fear, but it hasn't gotten any worse. I'll keep an eye on it. I really should clean it thoroughly and see if it returns.

I don't have any issues with losing oil or anything.
 

23 Explorer ST

23 Explorer ST

Member
Firefighter/EMT
#15
Messages
280
Reactions
157
Points
37
Location
NC
Vehicle
2023 Ford Explorer ST
#15
jwuonog said:
That is my fear, but it hasn't gotten any worse. I'll keep an eye on it. I really should clean it thoroughly and see if it returns.

I don't have any issues with losing oil or anything.
Click to expand...
Keep us posted what you find. Could be just a very slow minor leak.


Sent from my iPhone using Tapatalk
 

OP
jwuonog

jwuonog

Member
Thread Starter #16
Messages
221
Reactions
89
Points
27
Location
Jessup, MD, USA
Thread Starter #16
I cleaned it thoroughly with some brake cleaner and engine degreaser, it hasn't returned so far.

I think it may have just been residual oil from when I had the FADA leak addressed a few months ago.
 

You must log in or register to reply here.

Explorer ST Posts



Top