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transmission fluid in my coolant....

7051 Views 7 Replies 3 Participants Last post by  dieselenthusiast
Ok...Im faced with what appears to be a huge problem.
i have trans fluid in my coolant....after doing some searching im concluding my torque converter cooler or trans heat exchanger has failed.
first off..What or how do i proceed in fixing this thing?
Is there any step by steps on removing or eliminating this ? all I have found in searches is people suggesting to remove it before problems...but I already have a problem?
what is the proceedure...( i just put a water pump on it and did a coolant flush service 13k ago..FWIW)
Can someone steer me in the direction of protocol for what to do first?
I have cooant in trans
i have transfluid in coolant.
now what..? as i understand it the exchanger is a PITA to work on..
I need to read up on the protocol to remove by pass and or what to do in my situation.
any help ..links or advice..?
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Removing the heat exchanger is the easiest and cheapest. If you warm the trans in really cold conditions and run a radiator block you can do with out it, just takes fore thought.

Engine is realtively easy to flush. granulated diswasher soap and multiple flushes is easiest.

Transmisison is the problem. The coolant mixed with fluid crates a sludge that will sit in all the dead end passages and nooks it can find. Water in the coolant eats the glue on the frictions and they come apart. There is no fix but a bebuild and a thorought cleaning of the trans. You can flus it severla times with good fluid and it will work if nor too much collant has gottne in there but will always be a potential failure point.

Soory, absolutely no good news when that happens.
i put a section of hose to connect the coolant lines and bye passed the coolant lines into and out of the exchanger.
I then did the same for the trans fluid lines..basically added small section to the in and out lines and skipped the exchanger...
i am getting ready to drain the trans and put a new filter and fluid in it.
it mostlikely is in need of a trans rebuild anyway ..but i was trying to nurse it with the new governer pressure switch and overdrive selonoid and harness..just did this a few days ago...
im gonna cross my fingers..i need 5k for a new trans..hope this doesnt put me out of commission before i can arrange a new trans.
its got pink fluid in its contaminated pretty good..will see with the pan dropped..
atleast this happened before i got a new transmission and T/Q
thanks for your quick response..

fwiw i thought at first it was a head gasket...not sure if im glad it was not the head gasket at this point cost
Ok an update.
basic radiator flush with detergent..ill drive it a day or so and flush it a few times..its pretty nasty.
i loosened and removed the trans lines that run in and out of the coolant exchanger..i then cut off the flare nut and fitting which created a straight pipe end...i did this to both lines...then i added a small section of rubber trans line of the correct diameter 1/2 ID. and two hose clamps and completed the connection effectively bypassing the exchanger.
i then did the same to the coolant line..its a aprox 7/16 ID. with coolant line.
and two hose clamps..
this allowed me to bypass the exchanger all together..
i then pulled my pan..and found pink milkshake trans fluid so i drained the fluid . cleaned the pan wiped off every think i could on the exposed valve body and replaced the filter and pan. I filled it with new ATF4 . and let the truck warm then took it for a test appeared to function as is it did before the mishap. I put about 15 miles on it..of normal driving.
tomorrow i will dump and replace the trans fluid again..(walmart was out of ATF4) its late on a ill do this agian and report back.
I am or was expecting to rebuild/upgrade the trans soon..and have been doing my home work..and its i need to buy some time to acquire the funds for a new trans.. fingers crossed i hope i can make this last until then.
i have just under 200k and believe its the original trans.
Bypassing the exchanger only took about 45 min..and my only reservation was cutting the factory lines..(i have a truck salvage yard not far "crest truck salvage" )so I can get replacements if i have to at a later point.

i live in Georgia and it doesnt get real cold..or atleast only in the early mornings so ill just run/plug in the block heater in the coldest weather (mostly for convenience and quick heat)and let the trans warm up before i leave on cold mornings..i have a fluid trans temp gauge.

If i knew more detail about this calamity before i may have bypassed it sooner...

ill report what the fluid looks like after this first flush and report...on how many times it needs to be drained and filled to clear it up.
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In Gerogia, unless we see a major climate shift, I would not even worry about replacing the heat exchanger. The themostat in the front cooler will help it warm fast enough in any conditions we see here. The only thing you might do is add a secondary thermo activated cooler with a fan if you tow heay a lot. The heat exchanger removes a LOT of heat in the slow moving hot conditions.

Sometimes you get lucky and flushing it enough will but you time. I have never seen one yet that has lasted any amount of time if the fluid looked like strawberry milk. A little discoloration adn usually you can get by but that much is almost always fatal. Might get you 20k or 2k, hard telling.
cerberusiam, how common is this type of failure? Since I have an auto, I'm wondering if I should be proactive and do something prior to a heat exchanger failure. I live in the mountainous regions of northern New Mexico where temps can get down to -30. I don't drive the truck much during the winter months. What would you do in my shoes?
This failure is just not that common considering the numbers. There will always be a few that are an actually quality issue with the part but my guess is a lot of the failures are self induced.

Removing\replacing the lines, adding a line with a temp port in it, etc, seems to contribute more than anything. The fittings MUST be held on the back side with a wrench when the line is installed or removed. Not doing that is causing cracks and internal failures.

The heat exchanger is a pretty well made piece for what it endures.
Aside from bad maintenance practices, its failure is probably no more frequent than the oil cooler.
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Thanks cerberusiam, I think I'll leave mine alone! :thumbsup:
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