SOLVED! Coolant in transmission fluid

tucker12

Registered Member
Well I get the dumbass of the year award. Turns out my issue was not putting the big 21mm bolts on that hold that lower control arm/bracket in. when the rack was turning it pushed it out and it making it all messed up. I pushed the lower control arms in as far as they go and bolted it all up and she turns great with that new pump and fluid.

Now to the bigger issue. I drove her 1/3 of a mile round trip to the speedway to give her some fresh gas. on the way back she didnt want to shift at all. Pulled the dipstick and its straberry milk colored. Somehow water/coolant from the radiator is getting into the trans. I parked it immediallty at this revelation.

From my understanding and what my dad tells me. I have to replace the radiator or get a separate trans cooler, drop the pan and drain all the bad fluid out by removing the cooler line and pouring new fluid in until it comes out good.

I thought I would run this by the hive mind before I do anything.
 

MRRSM

Lifetime VIP Supporter
Because Anti-Freeze-Colant Chemistry is quite actively Acidic ... If you find a "Brown Gravy" on your Engine Oil Dip Stick, you will need to drain the Old Oil and R&R the Oil Filter and then re-fill the Crankcase with Cheap Organic 5W-30. Pull the Spark Plugs, the Fuel Pump Relay and the Coil On Plugs Fuse and with a Battery Charger hooked up... Cycle the Motor in (15) Second Intervals separated by (5) Minute Breaks to avoid damaging the Starter Motor. This will flush the out the GM DexCool,"OAT" Organic Acid Technology acidic mixture from within the Oil Galleries. If you do NOT find any issues with the Motor Oil... then the Strawberry Color could mean that Automatic Transmission Fluid is migrating into the Water Column of the Radiator via a Failed ATF line Coil inside of the Radiator.

Just to be on the safe side... Remove and leave the Spark Plugs OUT during this investigation so you don't accidentally Hydro-Lock the Pistons and Connecting Rods during Engine Turnovers and examine them for Cleanliness. Observe whether or not any of the Piston Tops are Shiny and Clean. Anti-Freeze tends to scour Carbon Deposits whenever these situations occur and its presence within certain Cylinders will narrow down where the MLS gasket has leaked. You've got to figure out ALL of the possble pathways that these Fluids might be using to get Cross Contaminated.

If the Oil Flushing becomes necessary, hopefully this effort will prevent the Bearings from suffering from Electrolytic Corrosion setting up in between the Crankshaft and Con-Rod surfaces and the Wrist Pin bosses of the Connecting Rods. You could also try using the alternative mixture of (6) Quarts of Cheap Organic Motor Oil and One Quart of ATF. Be meticulous in this effort and Check for the appearance of the Oil on the Dip Stick after cycling the Motor Oil through the Engine Block for any additional presence of the Odd Mixture. It may take several Flushing Procedures to get rid of all this Stuff.

When the engine was running... did you happen to notice any "White Smoke" billowing out of the exhaust pipe? This would be a sure sign of the presence of Propylene Glycol or Di-Propylene Glycol entering the Cylinders from a poor MLS Head Gasket leak. Normally... a "Chocolate Pudding" appearance of the Motor Oil develops as more and more of the Coolant invades the Oil Pan and gets mixed together with Motor Oil during the running of the Engine. The only other source for this problem will come either from having a Cracked "Lost Foam" Engine Head or from within the Engine Block Casting along the Water Jacket to oil Gallery areas.

At some point, you might need to Pull the Valve Cover and lightly attempt BY HAND ONLY to unwind the Head Bolts using an H-10 Hex Socket fitted to a 3/8" short Extension... using ONLY Finger Pressure in order to seek out any Broken Bolts that may have Snapped Off during Engine Heating will become immediately evident as this is another possible cause of having a Lost Head Gasket Seal. Finding any Broken Bolt Shanks will indicate a TTY Bolt Failure just after Engine Head Installation.
 
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Because Anti-Freeze-Colant Chemistry is quite actively Acidic ... you will need to drain the Old Oil and R&R the Oil Filter and then re-fill the Crankcase with Cheap Organic 5W-30 . Pull the Spark Plugs, the Fuel Pump Relay and the Coil On Plugs Fuse and with a Battery Charger hooked up... Cycle the Motor in (15) Second Intervals separated by (5) Minute Breaks to avoid damaging the Starter Motor. This will flush the out the GM DexCool,"OAT" Organic Acid Technology acidic mixture from within the Oil Galleries.

Leave the Spark Plugs OUT so you don't accidentally Hydro-Lock the Pistons and Connecting Rods during Engine Turnovers and examine them for Cleanliness. Observe whether or not any of the Piston Tops are Shiny and Clean. Anti-Freeze tends to scour Carbon Deposits whenever these situations occur and its presence within certain Cylinders will narrow down where the MLS gasket has leaked.

Hopefully, this effort will prevent the Bearings from suffering from Electrolytic Corrosion setting up in between the Crankshaft and Con-Rod surfaces and the Wrist Pin bosses of the Connecting Rods. You could also try using the alternative mixture of (6) Quarts of Cheap Organic Motor Oil and One Quart of ATF. Be meticulous in this effort and Check for the appreance of the Oil on the Dip Stick after cycling the Motor Oil through the Engine Block for any additional presence of the Odd Mixture. It may take several Flushing Procedures to get rid of all this Stuff.

When the engine was running... did you happen to notice any "White Smoke" billowing out of the exhaust pipe? This would be a sure sign of the presence of Propylene Glycol or Di-Propylene Glycol entering the Cylinders from a poor MLS Head Gasket leak. Normally... a "Chocolate Pudding" appearance of the Motor Oil develops as more and more of the Coolant invades the Oil Pan and gets mixed together with Motor Oil during the running of the Engine. The only other source for this problem will come either from having a Cracked "Lost Foam" Engine Head or from within the Engine Block Casting along the Water Jacket to oil Gallery areas.

At some point, you will have to pull the Valve Cover and lightly attempt to unwind the Head Bolts using an H-10 Hex Socket fitted to a 3/8" short Extension...using ONLY Finger Pressure in order to seek out any Broken Bolts that may have Snapped Off during Engine Heating as this is another possible cause of having a Lost Head Gasket Seal. Finding any Broken Bolt Shanks will indicate a TTY Bolt Failure just after Engine Head Installation.


Ummm, I am fairly sure he was talking of the TRANSMISSION fluid dipstick and not the engine oil dipstick.
 

MRRSM

Lifetime VIP Supporter
...Agreed... but ALL of the other possible Fluid Cross-Contamination should also be looked at so soon after the Engine Head R&R... Just to be sure the Machinist performed the TIME-SERT Repair 100% Perfect, too.
 
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paul2005tb

Active Member
1) disconnect the transmission cooler lines from the radiator (the internal trans radiator sits in the engine radiator).

2) flush the transmission two times. Use the cheaper older generation fluid during the flush.

3)install a new stand alone transmission cooler/radiator.

4) fill with fresh transmission fluid.
 

NJTB

Silver Supporter
Coolant in the trans fluid will damage the transmission real fast. Like your dad said, replace the radiator (problem is the trans coolant tank in the bottom of it is cracked), and flush the trans until there's no evidence of engine coolant. Replace the trans filter.
Good luck.
 
the transmission fluid will cause "significant" issues with any clutch material causing delamination and such. Depending on how long the problem (mixed fluids) existed before the shifting problem appeared. :-( Odds are high that your tranny will have further problems.
 

tucker12

Registered Member
Thread Starter
Sorry I have been MIA. Work has been extremely busy
I have fixed this issue. I wish I took pictures, but working with dad I end up holding the flash light or finding him Tylenol.
Just to preface this, I didn't take anything apart in the transmission. With 210k miles on her, we figured its better to let sleeping dogs lie, Especially since we change the fluid every 30k.

What I ended up doing with my dad after the discovery of the milkshake in the coolant and the trans was:
Draining the coolant,
Droped the pan[there was very little debris in the pan]
removing the trans filter and sprayed the underneath of the trans with non chlorinated brake clean.
As that dried, We removed my custom braided trans lines and made a new pair from 6an hydraulic braided line. We also removed the 6an to 4l60e side connectors and cleaned them.
Installed a hayden standalone trans cooler. In front of the ac radiator
Plugged the stock trans cooler inlet/outlet with jb weld
Installed a new filter,
Bolted pan on
Filled with dex3
Installed lines. Put discharge line in a oil drum
Put a funnel in the dipstick
Ran to every autoparts store. Ended up buying 15 gallon jugs of dexmerc
Started the truck up and fed her fluid, keeping her fed and shutting her off once we ran out but before the pump had spit out air. After all that fluid it was coming out dark cherry red.
Dropped the pan, cleaner than a new dinner plate,
Removed filter
Cleaned everything again with cleaner
Went to the gm dealer and bought 14 quarts of AcDelco Dex 6 full synthetic and a delco filter
Installed the filter and pan
Fed her 12 quarts of the delco dex 6
Hooked the lines back up.
Put her on the ground, level.
Checked the fluid level cold.
Added a bit.
Idled till warm.
Checked it again
Cycled through the gears going up and down the drive
Checked again
Its deep dark red at the crosshatch
Prayed to the hydramatic gods
Drove her around town with dad. Shifts like butter.

Since I did this I've put 300ish miles on her and no leaks, no weird shifts. I've checked the fluid twice since then and its still red and full.

The only issues I have now with the envoy is traction control/abs and the class 2 com issue [I think its the aftermarket radio my dad installed in 2006 causing that]
I will drop the pan and change the filter again before it gets snowy just to see what's in the pan and put a fresh filter in. I will let you know if anything changes.
I also flushed the cooling system with alot of water, Its just plain water now, clean plain water. I have dexcool in the garage. This weekend will be another flush or two then a proper coolant fill.

Thank you all for the suggestions and help.
-matt
 

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