Milky White ATF, Please Help!

RE: 2010 Tahoe LT 5.3L, Hydra-Matic 6L80 6-speed rear-wheel-drive transmission, 75,450mi

Hi Members,
I was just doing a fluid check on my Tahoe and noticed the dip-stick tube so loose it felt like it was off of the transmission housing. I carefully pulled out the dip-stick and almost freaked out! My ATF was white, like milk!
I just returned from a long trip, a week ago, using this truck to drive about 1500 miles. For 1000 of those miles, I was pulling 2000 pounds!
I need to fix that dip-stick tube and flush that milky fluid. Any help would be appreciated. Thank you,
Prof H :runaround:

It could be milky for a few reasons.

I would venture guesses that it is milky from being a little low and the milkyness is frothing. Or the radiator is leaking into the trans cooler, meaning a new rad is on order too.

Just checked the radiator fluid, can't really see much into the storage tank other than it has pink antifreeze, which is what it always had. The radiator is sealed, no cap, so can't really see inside the radiator.
I think water got into my transmission via the broken dip-stick tube, could this be a possibility?
Truck is running and shifting perfectly, I didn't even know anything was wrong. I check the fluids often, so any low fluid level, I would have noticed. Didn't notice "froth/foam" just liquid white on the stick, not even pink, white.

The only way to prove your theory on the broken dipstick is to check the fluid again. I honestly can't see how enough water would get in that way to make the milkyness you saw though.

Okay, will check the fluids again. Rad fluid should be clear pink, right? If it is mixing w/tranny fluid it would be milky as well, right?

Since I don't have a rad cap, do I remove the top rad hose and check fluid inside? I don't want to cause an air pocket, as I've heard on these sealed units, this can be a problem.

Okay, will check the fluids again. Rad fluid should be clear pink, right? If it is mixing w/tranny fluid it would be milky as well, right?

Since I don't have a rad cap, do I remove the top rad hose and check fluid inside? I don't want to cause an air pocket, as I've heard on these sealed units, this can be a problem.

guessing I would say the radiator tranny cooler is with a leak from the engine coolant . coolant pressures are high tranny pressures low at idle so the way to find out is the fluid in the tranny will be high level . tranny fluid in coolant hard to see.

also being too high the fluid will have bubbles in it because of this .

the tranny dip stick tube maybe defective GM part . some have had this occur it fractures !

you drive threw any deep water cause the water can enter threw the tranny vent tube .

the fluid if it does have these issues will require the fluid exchange method to remove this water. the pan is dropped and the filter replaced . filled with about 5QTS . then before starting the radiator tranny cooler line is disconnected . engine started and as the fluid comes out you installed fluid in the dip stick requires 2 people though you can do it with one but will have to shut down the engine several times. will take about 12-14QTS you do this until its a nice red color. then adjust the fluid level.. I use a 4 ft 3/8 plastic tubing down the dip stick and a hand pump to suck out any over filling .

RE: 2010 Tahoe LT 5.3L, Hydra-Matic 6L80 6-speed rear-wheel-drive transmission, 75,450mi

Hi Members,
I was just doing a fluid check on my Tahoe and noticed the dip-stick tube so loose it felt like it was off of the transmission housing. I carefully pulled out the dip-stick and almost freaked out! My ATF was white, like milk!
I just returned from a long trip, a week ago, using this truck to drive about 1500 miles. For 1000 of those miles, I was pulling 2000 pounds!
I need to fix that dip-stick tube and flush that milky fluid. Any help would be appreciated. Thank you,
Prof H :runaround:

Hello Prof_h,

We regret to hear that you have discovered a strange color liquid in your ATF. As we certainly can understand your concern with this, please be advised that any transmission flushes should be done at the dealership level. I would be more than happy to facilitate in setting an appointment for you to have this concern addressed. If this is something you are interested in please send us a private message with your full contact information, VIN, and the mileage of your vehicle.

Best,

Netty J.
Chevrolet Customer Care

Had the truck flushed at the Dealer. Dealer didn't have the dipstick tube, so I went to a local mechanic and he said it took two guys two hours to get that dipstick tube out and the new one in. It was a bear. He did a pressure check of the radiator and there are no leaks. We are all stumped as to why my fluid was so milky.

Pressure check of the radiator will not show a leaking internal trans cooler.

Had the truck flushed at the Dealer. Dealer didn't have the dipstick tube, so I went to a local mechanic and he said it took two guys two hours to get that dipstick tube out and the new one in. It was a bear. He did a pressure check of the radiator and there are no leaks. We are all stumped as to why my fluid was so milky.

they replaced the dip stick tube yes ? if they did then it was broken yes ? that would do it esp if you drove thru deep water.

Monitoring the cold radiator pressure with a tester/cap while pressurizing the engine oil cooler or transmission cooler with air can reveal leakage. The pressure in the cooling system will increase if there is leakage in either of the tanks.

Yes, the trans. dipstick tube was replaced, my truck has been running fine and was checked by a respectable mechanic, so I'm sure he checked things when he tested the cooling system and told me there were no leaks.
Thank you all for your comments to this post. I did run through a deep puddle on a trip, so maybe that was where I got the water.