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Help>transmission Leak

  • Thread starter Thread starter allblknblue
  • Start date Start date Sep 21, 2015
  • Tags Tags
    aod trans leak transmission leak
A

allblknblue

New Member
Sep 14, 2015
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Sep 21, 2015
#1
  • Sep 21, 2015
  • #1
I have a 91 notch 5.0 (Auto) and I am having issues with diagnosing where my trans leak is coming from.
The fluid is dripping from the exhaust and cross member. I thought the leak was coming from the trans pan (about 2-3 drops per day). I thought the gasket was bad so bought a replacement and installed. The problem persisted and this time even worse than before (2-3 drops per minute!). I figured the pan was probably bent somewhere so I invested in a new Summit deep pan with a Moroso gasket. When I was installing the new pan, I got everything bolted up ready to be torqued and realized that one of the threads was stripped and was causing the bolt to spin and not tighten. I went and got a helicoil and drilled out/tapped. I reassembled the trans pan and thought everything was good to go. I added half the fluid and nothing was leaking like it was before. I started the car and added another qt. about an hr later I went back to check and it was still leaking (about a 1/16th of a qt).

I am at a loss as to what else could be leaking, it does not appear to be coming from the bellhousing or anywhere up above. has anyone had experience with this or know other possibilities of what can be going on?

any help is greatly appreciated.
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
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Sep 21, 2015
#2
  • Sep 21, 2015
  • #2
Get some brakekleen parts cleaner...spray it down... Patiently watch. A lot of parts stores sell a UV dye you can add to the trans fluid. I've never had to go that route. Usually if you clean everything off and use a mirror you can find any leak.
 

mikestang63

SN Certified Technician
Aug 27, 2012
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In the garage
Sep 21, 2015
#3
  • Sep 21, 2015
  • #3
what side of the trans is it leaking on? There are about a dozen places it can be leaking from. Did you check to see if the dipstick tube is properly seated in the trans?

Wipe down the entire bottom and sides of the trans so it is dry and then get back under and inspect every side of the trans. You can take some foot powder spray and spray it around the trans pan, lines, etc. and it will then show you where the leak is.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Sep 22, 2015
#4
  • Sep 22, 2015
  • #4
I bet it's a trans cooler line leaking
 

89oem

Mustang Master
Dec 18, 2013
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Sep 22, 2015
#5
  • Sep 22, 2015
  • #5
check your speedo cable, if there is fluid follow it, there is a possibility your speed sensor or the o-ring could be leaking.
 
A

allblknblue

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Sep 14, 2015
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Sep 22, 2015
#6
  • Sep 22, 2015
  • #6
It is leaking on the passenger side only - speedo cable looked dry. Honestly, everything looks dry above the pan but with the exhaust and egr feed, it makes it hard to see. I am leaning toward dipstick or cooler lines but haven't gotten a chance to look yet.
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
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Sep 22, 2015
#7
  • Sep 22, 2015
  • #7
It's been a while since I've had an auto but I thought all of those were on the driver side?
 
A

allblknblue

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Sep 14, 2015
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Sep 22, 2015
#8
  • Sep 22, 2015
  • #8
The cooler lines are on the pass side but completely dry. It actually appears as if most of the fluid is coming out of the top of the bolt holes with a little bit coming out of the dipstick tube. When we refilled the trans, we put 4 in then checked then 2 after that and we think we may have overfilled? The capacity is 7 tho?
 
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