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Discussion Starter · #1 ·
Hi everyone. I did search i promise... Ok, my 1994 K1500 Ex Cab 4X4 with 170k miles on it has transmission fluid leaking from what appears to be somewhere above my oil cooler lines where they go into the oil filter adapter. I can see anything from the top, and looking from below all i can see is the oil filter housing. What is above that that could be leaking transmission fluid? I'm stumped!
 

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Power Steering high pressure hoses are right above the oil filter.
A lot of people are using ATF for P/S fluid.

Those hoses are covered by plastic loom so it is not easily seen when leaking.
 

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Discussion Starter · #3 ·
Interesting...what's the best way to access them? from the top or underneath?

Could it be the transmission pump itself leaking out the front? the leak seem worse when i was parked with the front downhill on my driveway...
 

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It is right there when you open the hood go to the driver side and you will see a few hoses crisscrossing each other.
Cannot miss it.
It is usually the part where it has hydraulic crimps from metal tube into rubber hose.
Those crimps gave up.
Same type of crimps on the oil cooler lines, brake lines, AC lines.

To replace it is a different story.
One of the end goes to the Steering Pump and it is accessible from the bottom unless you are a really tall person then you can hunch over it from the top.
It has been a while, so this is my recollection.
 
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Discussion Starter · #5 ·
It is right there when you open the hood go to the driver side and you will see a few hoses crisscrossing each other.
Cannot miss it.
It is usually the part where it has hydraulic crimps from metal tube into rubber hose.
Those crimps gave up.
Same type of crimps on the oil cooler lines, brake lines, AC lines.

To replace it is a different story.
One of the end goes to the Steering Pump and it is accessible from the bottom unless you are a really tall person then you can hunch over it from the top.
It has been a while, so this is my recollection.
I just checked something...the fluid leaking is bright red...the fluid in my PS pump is brown and smells like brake fluid...so i'm back to thinking maybe the front of the transmission pump is leaking and it just happens to be leaking out through by the filter housing?
 

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I just checked something...the fluid leaking is bright red...the fluid in my PS pump is brown and smells like brake fluid...so i'm back to thinking maybe the front of the transmission pump is leaking and it just happens to be leaking out through by the filter housing?
I would invest in a cheap inspection camera like harbor freight and inspect the area to see what you can find
(y)
 

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I just checked something...the fluid leaking is bright red...the fluid in my PS pump is brown and smells like brake fluid...so i'm back to thinking maybe the front of the transmission pump is leaking and it just happens to be leaking out through by the filter housing?
That can be. Check everything as OkD said with camera.
Is the ATF level go down?
Is the P/S fluid level go down?
Is the oil level go down?
Is the brake fluid level go down?

The ATF may also be brown unless you just changed it.
 
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Discussion Starter · #8 ·
That can be. Check everything as OkD said with camera.
Is the ATF level go down?
Is the P/S fluid level go down?
Is the oil level go down?
Is the brake fluid level go down?

The ATF may also be brown unless you just changed it.
I'm stumped... I went on my hunt...so no time to buy the camera yet...but everything seems to work fine...i'll check the fluid level tomorrow... But what's weird is if i part the truck with the front pointed downhill...it leaks worse. Now...maybe it's pooled up somewhere and when pointed down it pours out...but i'm stumped. I took it to two shops and they glanced at it...one said it's not trans, the other said it's not the trans but some hydro boost thing...but I don't see anything there...
 

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I'm stumped... I went on my hunt...so no time to buy the camera yet...but everything seems to work fine...i'll check the fluid level tomorrow... But what's weird is if i part the truck with the front pointed downhill...it leaks worse. Now...maybe it's pooled up somewhere and when pointed down it pours out...but i'm stumped. I took it to two shops and they glanced at it...one said it's not trans, the other said it's not the trans but some hydro boost thing...but I don't see anything there...
Usually, when the hydro-boost leaks, the frame rail directly behind the driver's side, front tire will become wet from leaking fluid.
 
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Put some fluorescent die in the P/S pump and find where it is leaking.
 

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Discussion Starter · #11 ·
Put some fluorescent die in the P/S pump and find where it is leaking.
I will try anything and will get some die. When I checked my power steering fluid...it's brown and smells like brake fluid...the stuff leaking is bright red transmission fluid. The hydro boost uses the power steering or brake fluid doesn't it?
 

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Bright red and 2 mechanics say it's not ATF? That's strange.
Hold off on the dye and try this.
P/S fluid should be clear, but some have added or changed to ATF.
The HB uses the P/S pump pressure.
Master cylinder and HB fluids do not mix.
There is a vent between them on the bottom to prevent that.
Take a white rag or paper towel and let the mystery drip collect on it.
Then put a sample of your ATF from the dipstick and a sample of the P/S fluid
on the rag and compare.
 

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Discussion Starter · #13 ·
Bright red and 2 mechanics say it's not ATF? That's strange.
Hold off on the dye and try this.
P/S fluid should be clear, but some have added or changed to ATF.
The HB uses the P/S pump pressure.
Master cylinder and HB fluids do not mix.
There is a vent between them on the bottom to prevent that.
Take a white rag or paper towel and let the mystery drip collect on it.
Then put a sample of your ATF from the dipstick and a sample of the P/S fluid
on the rag and compare.
Ok. Fair enough. Will be plenty easy to do... I'll do that in the morning and post pics. Thank everyone so much for the help!
 
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