Oh? @thegreendrag0n ? I wasn’t aware…or maybe thinking of the process as having that option. Perhaps so Grasshopper…perhaps so…
This is what’s coming out of the vent tube
It appears you’re looking at a radiator replacement job. Also if even a little coolant got into the transmission fluid through a defect in the radiator’s transmission-cooler loop, it’s very important to get all the coolant removed from the transmission and torque converter. Otherwise corrosion will get a toe-hold inside the transmission, and that’s no-good.
Radiator is being replaced as we speak, it’s at the shop now. I’m just hoping the leak hasn’t caused transmission damage beyond what just a flushing can repair. I think it might though because that nasty white sludge really seems to be a death note for transmissions. And seeing as the trans won’t engage into gear I think I’m looking at bad news however it goes. Anyone know about what it costs for a new (Used) transmission in one of these? I assume over $1000
for this case, I would rather be concerned about electronics (valves block) getting damaged first.
Check sites like http://car-part.com/ to get an idea about availability and costs.
If you get lucky, it may be not far from your location.
Why valve block electronics? Not too sure what that means but how would this effect it?
Valves block is inside and is immersed in fluid.
Fluid is supposed to be not electrically conductive.
Now, having water/coolant there…
That’s actually the scenario of Nissan R51 failure I mentioned above, it was reported to fail very fast from the leak to the irreversible damage.
Inside of the engine? Or transmission
I’d guess well over $1000. More like $2500-$3500 for a warranted used transmission, w/parts and labor. If I had that problem I’d remove as much coolant from the transmission as possible, replace
the radiator, and cross my fingers. If there were still remaining transmission problems I’d give up and move it on. This problem may prove a tough nut to crack.
Transmission.
These valves control ATF flow/pressure, which actually engages gears.
Hard to guess for me.
I helped a friend of mine to swap transmission on his old Toyota Echo.
He paid $200 for transmission with under 50K on it from the local salvage yard, we made a swap in one day, it works great for a year already.
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OK… wait a minute. I think I might want to revise my assessment … Not that the diagnosis of the trans cooler is the culprit…but after thinking about it a moment I will now say that yes… the trans cooler failure CAN actually allow coolant to get into the trans.
The heat exchanger that is the “cooler” runs trans fluid in a sealed metal tube through the rads coolant…thus cooling it. If that tube carrying the trans fluid were ruptured it would introduce trans fluid into the coolant… However the return line going back into the trans…could then suck up coolant and run it back into the trans (as part of its circulation of flow, In and Out basically.
So I am now in agreement with @thegreendrag0n on this type of failure mode (had to ponder that a moment). But that failure of the trans cooler tube would need to be rather severe in my opinion. Certainly possible. Usually the breech is a small crack that only allows a one way contamination of trans fluid into the coolant.
Don’t be confused about the sludge or milk-shaky consistency of what you are seeing. This is precisely what oil and water will look like when combined in various systems in vehicles. Technically that milkshake is made up of two-ish items… Coolant and Trans Oil… If you put the milkshake stuff in a glass jar and let it rest a good long time, you will literally see the Oil come out of suspension in the coolant and sooner or later in that jar you will see two distinct liquids…Actually maybe even three… Ethylene Glycol, Water and Trans Oil actually. Ugh…
What you are seeing is what happens when they are mixed together violently by moving parts such as the spinning water pump impeller…and or anything moving inside the trans…like the inside of the torque convertor, the trans pressure pump etc… Those items will be able to mix them together to form that substance.
So wherever you find milkshake…that’s basically oil and water in suspension, a normal suspension of fluids…and the abnormal condition that allowed them to be mixed together.
so… once we settled that indeed we might have water/coolant in the transmission, and once we correlate that to “gears do not engage”, the failure scenario becomes quite clear
let’s assume @Oliver_Pantoto does next steps:
- replaces failed radiator
- flushes engine coolant system
- flushes transmission (many times!)
the mystery question is: will it suffice to recover transmission functionality?
I would say “flip a coin and check if you are lucky”
first two items need to be done regardless of transmission
some cheap ATF of compatible spec will be the bet… if it works, bingo!.. if not, it will be wasted, but it’s not that much to compare to transmission replacement costs
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That’s the plan, fingers crossed. Thanks again for the help everyone
if you get to replacing transmission, make sure to blow air through ATF loop in radiator to remove any remaining water (which may get there from experiment of attempted old transmission CPR)
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Agreed… I think this is a “Recoverable Shituation”… If you really want to split hairs and in a laboratory setting… Technically could fill both the rad, and trans and torque convertor with Coolant or water and it would function… for a time, at some capacity…
So…with careful measures and proper flushing… I dont see why this issue cant have a happy ending.
I say go for it man.
When I was buying my R51 Pathfinder, I researched their failure areas in depth, and this “ATF cooling loop” was really the only scenario which might result in really bad failure, so once I found on the 2006 one I was about to buy the radiator was replaced in 2012, with updated OEM part, I wrote a check on the spot (given the rest of the car passed my inspection).
So… I’m a little bit familiar with the similar issue, although on another make/model.
From what I knew of R51, if owner recognized failure in time and if flush was performed, sometimes the coin landed luckily, but much more often, the car was kept driven for few more days, until transmission was completely destroyed.
Hopefully, @Oliver_Pantoto will get on lucky side 
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I wonder what the trans cooler loop has to look like to be able to suck coolant into the return side of the trans. It must literally snap the tube in half or something. Usually the breech is like a crack or a seep type area within the tube wall or something.
It’d have to be a fairly large breech to cross pollinate the way we are discussing… Traditionally its ATF in the coolant and not much more… but… yeah I can see how it would be able to cross over. Not pretty.
But I think its recoverable… I’d sure as hell try, I know that.
Just from my memory on R51 OEM radiators… they used to have the loop attachment points to develop some kind of crack on the return side, right in connector, where the pressure of ATF was lesser than pressure of coolant and the rest was the history of Nissan’s R51 owners nightmare: no reverse gear first, quickly followed by complete failure.
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Jeezoo… Yup… That’d do it now wouldn’t it. Rather shocking for Nissan… or at least it should be considered so if you been around long enough to remember what a Datsun was…
Nissan seems to have fallen from grace quite a ways… It used to be in tight formation with those two other Japanese titans of reliability. I personally don’t like seeing that happen honestly as I have loved several Datsun and Nissans in my day.
Dare I say…it’s happening to those other two a little bit now too isn’t it? smh