Coolant in ATF - 2007 GM 6.0L w/ 4L80E

[illusha]

My radiator seems to have a leak. Coolant is low. ATF level is high by 2-3 quarts (maybe more). Will get a pressure test kit rented. Just getting started.

Working on a 2007 Chevy with 6.0L and 4L80e with deep pan and no aux cooler. Running red ACDelco DexCool in radiator. Switched to TranSynd-668 from Dexron-VI. Double flushed 10K miles ago. Checked tranny fluid level and drove around 200 miles, a few days, then noticed the motor started running hot quick after initial startup, checked fluids, here I am. Going to replace the radiator with OEM of course, and no, I don't want to eliminate the internal radiator cooler. How can I save the tranny?

Questions:
- is red Dex Cool much different from green coolant in acidity (I think its PH is 8.7 or so)?
- is TranSynd much different from Dexron-VI ATF in stability and does anyone know their PH specs?
- any ideas on using test strips or anything else to test TranSynd 668 ATF for coolant presence?
- can anyone enlighten me about different test strips, some test Molybdate (MoO4) and Nitrate (NO2), some just PH?
- does coolant in ATF mean a certain death of tranny clutches and/or converter or is there hope?
- can torque converter in 4L80 drain back if pan was dropped for a few days, I doubt it, but double checking?
- what's the best method to change the ATF here - pump flushing leaves fluid in valvebody and clutches - pan draining leaves fluid in converter?

 

[burbguy82]

I would say that if your transmission is 3 quart overfilled with coolant, it would likelike be a dead tranny pretty quick. Is the ATF milky?

 

[Lubener]

Coolant in the transmission will destroy clutch and band material. Your best bet is to flush out all ATF ASAP, replace filter and hope for the best. I would have a good transmission shop do this as they may have what is necessary to get all contaiminated ATF out.

 

[vwmaniaman]

I would guess you need to start finding one at the U-Pull-it.

 

[zrxkawboy]

This is the one time I may seek out a shop that has a machine to do an ATF exchange. If you want any chance of saving your trans, you want all the coolant out of there ASAP.

 

[Marcozi]

ATF heat exchanger is the likely culprit.

 

[kschachn]

Please post a picture of the fluid condition.

 

[Kira]

Coolant in the transmission will destroy clutch and band material.

I read that the glues used to affix clutch material is water based; never a word about how long damage takes.
I wouldn't be surprised if a complete disassembly and rebuild was required.
How many miles on it?

A 2007 Chevy, you say. That's the same time period for the end of the bad Nissan inner-radiator cooling loops.

 

[jetman]

multiple flushes with fresh dex6, maybe even over fill it by a qt or 2 when doing these flushes.

 

[clinebarger]

I read that the glues used to affix clutch material is water based; never a word about how long damage takes.
I wouldn't be surprised if a complete disassembly and rebuild was required.
How many miles on it?

A 2007 Chevy, you say. That's the same time period for the end of the bad Nissan inner-radiator cooling loops.

Correct the water in the coolant will de-bond the frictions, If it's been sitting in the unit more than a few days....Looking at a 100% failure rate.

 

[Kira]

OP's vehicle, right?
So....completely rebuilding an 18 year old popular transmission (parts are likely available), while expensive and inconvenient, might be in order.
How many miles on it?
Why not eliminate the internal radiator cooler and add an auxiliary/external cooler?

 

[nascarnation]

Correct the water in the coolant will de-bond the frictions, If it's been sitting in the unit more than a few days....Looking at a 100% failure rate.

At Allison we had a series of failures from this, sent a service guy to look at the fleet, and it turned out they were garbage trucks that got pressure washed frequently and were getting a surprising amount of water through the transmission breather.

 

[illusha]

Let me put this topic to rest by stating that I think maybe the ATF level was not higher than it was before after all, it was checked when hot immediately after driving and that may have caused an error, previously it used to be checked when cold and after the truck has been sitting for a while, rented a pressure test kit and found a crack in radiator plastic near the PS lines, took a sample of ATF and sent it to Blackstone for Analysis + TAN just to be sure...

I got my original transmission-related questions answered by calling a few very reputable tranny builders, in short, they agreed that glycol is known to eat glue, but they also agreed that it won't hurt to first try changing the fluid to see if that helps before rebuilding anything, torque converter won't drain regardless how long it sits, some prefer just a double drain and some said it's ok to drop a line and use internal pump if you don't let it run dry and refill the fluid, some said it's ok to switch to using only an aux cooler and some prefer to leave the heat exchanger or at least have a thermostat in line...

Never got an answer here to a single question I've asked about PH or differences between different fluids, but got some info from other sources, so this thread can be closed, or carry on discussing, your call...

 

[clinebarger]

It's the water in the coolant that dissolves the bonding adhesive.

Large amounts of coolant/water will turn the ATF pink...Looks like a strawberry milkshake.

GM products are not known for ruptured trans coolers.

Only one way to remove coolant/water/ATF mixture from a transmission, Complete disassembly & clean every component, New frictions & a Converter.....Flush the cooler/s & lines.

 

[kschachn]

Never got an answer here to a single question I've asked about PH or differences between different fluids, but got some info from other sources, so this thread can be closed, or carry on discussing, your call...

It would have helped had you posted a picture of the fluid condition.

 

[demarpaint]

Odds are the transmission is done if 2-3 quarts off coolant mixed with the ATF and circulated through the system.

 

[Chris142]

I saw coolant in transmissions often at the Radiator shop. I have never seen a transmission survive it.

 

[MolaKule]

Never got an answer here to a single question I've asked about PH or differences between different fluids, but got some info from other sources, so this thread can be closed, or carry on discussing, your call...

PH of the disparate fluids should be the least of your worries if coolant contaminated the ATF.