Where is the transmission oil cooler located on the 2010 Tahoe?

[abdullah_Zahra]

I have found coolant in my transmission's oil after tearing the thing apart. What could cause this? My mind went directly to the radiator but I am kinda lost. I opened the coolant reservoir and there were no signs of oil in, however when the transmission was taken down, the "strawberry milkshake" fluid went out!
If anyone could please guide me to what is in need of replacement here? Where is the oil cooler that could cause this mixing up? Is it on the radiator itself? or is it externally mounted on these vehicles? because I have 2 radiators in my tahoe. A noticeable big one (major radiator), and a factory oem smaller radiator sitting in front of it?

 

[strutaeng]

On the inside of the radiator (engine bay side) you should see the transmission cooler lines on the passenger side. If you have an auxiliary transmission cooler (was more like a towing option), you will see in addition a small radiator type cooler on the grill side, may 8"x12"-ish. Not all vehicle had the auxiliary cooler, but all have the radiator cooler.

 

[Doubeleive]

I have found coolant in my transmission's oil after tearing the thing apart. What could cause this? My mind went directly to the radiator but I am kinda lost. I opened the coolant reservoir and there were no signs of oil in, however when the transmission was taken down, the "strawberry milkshake" fluid went out!
If anyone could please guide me to what is in need of replacement here? Where is the oil cooler that could cause this mixing up? Is it on the radiator itself? or is it externally mounted on these vehicles? because I have 2 radiators in my tahoe. A noticeable big one (major radiator), and a factory oem smaller radiator sitting in front of it?

replace the radiator, the passenger side plastic end cap of the radiator contains the transmission cooler inside it is not serviceable.

 

[petethepug]

Whoa, I hope you caught this in time to save the trans.

I’m starting to wonder if these higher milage trucks are losing the integrity of the body on chassis bushings.

Could body flex up front be enough to allow flexibility of the radiator that leads to cracks?

Had a buddy with an OBS burb that lost 3 radiators in 2 years. The last one that burst was an all aluminum HD unit.

There’s the scenario that your truck could have a standard radiator, a thinner condenser (a/c) in front of it and an even smaller trans cooler in front of that.

The main radiator can also have an internally shared heat exchanger for coolant and trans fluid.

 

[strutaeng]

Whoa, I hope you caught this in time to save the trans.

I’m starting to wonder if these higher milage trucks are losing the integrity of the body on chassis bushings.

Could body flex up front be enough to allow flexibility of the radiator that leads to cracks?

Had a buddy with an OBS burb that lost 3 radiators in 2 years. The last one that burst was an all aluminum HD unit.

There’s the scenario that your truck could have a standard radiator, a thinner condenser (a/c) in front of it and an even smaller trans cooler in front of that.

The main radiator can also have an internally shared heat exchanger for coolant and trans fluid.

What year OBS is your buddy's truck?

My brother bought a 90 rcsb project truck and shortly thereafter his radiator leaked into the ATF and ruined his 700r4. So he got it rebuilt and bypassed the radiator cooler. I've got a 00 k3500 beater truck and the radiator was leaking externally when I had just bought it. It had 200k, no telling if it was the original one or any history with the truck.

My 99 Silverado had 260k on the original radiator. I only replaced it because I wanted the wider version. My buddy has 2 rcsb Silverados, an 01 and a 03 with each over 400k. I believe he's replaced a few, but due to external leaks. Both trucks have the original engine and transmission, which is remarkable. I don't believe internal leaks on the NBS radiators are common at all as far as I know. I would imagine it the same for GMT900s as well...

...actually it's the first time hearing this condition on this forum since I joined.

Of course, anything with over 200k and 20 years+ old is likely to have failures of any parts due to age, wear and fatigue.

 

[Marky Dissod]

Only time that it is NECESSARY for ATF to run through the radiator's HEAT EXCHANGER -
it is NOT a 'cooler', the coolant is using the ATF as a heat sink to bring some of the ATF to 212F -
is during cold-weather warmups where there would be an MpG penalty to winter-cold ATF.

Spring, summer, fall, the ATF heat exchanger is not needed - just drive gently for the first 10min.

Once ATF reaches 176F / 80C, it's warm enough ... unless you want better MpG,
in which case you want the ATF @ 203F / 95C to 212F / 100C ...
which is why radiators have ATF heat exchangers.

If you fear ATF & coolant turning to a monty python flavored milkshake,
don't let ATF & coolant share circuits near each other.

Oh, and by the way, if your vehicle is over 10 years old, the radiator bushings need replacing, if not upgrading.
Bushings get brittle as they age. Every bump you're not afraid of goes right through to the radiator,
and the barrier between the coolant and the ATF gets weaker.
(Same goes for every other bushing, by the way, but here the subject is ATF vs coolant.)

 

[petethepug]

Not sure on the year of his OBS. He retired to Utah about 5-6 years ago. I just remember him being pissed about three radiators in a row taking a dump.