Here’s Why There’s A Strawberry Milkshake In Your GM Truck Or SUV Engine Coolant Tank41
Some owners of 2021 and 2022 model-year full-size GM truck and SUV models may notice a thick pink liquid forming in their vehicle’s coolant tank that looks a bit like a strawberry milkshake. This is no sweet treat, though, and could be a sign that the engine coolant in the vehicle has been inadvertently mixed with the transmission fluid.
This problem can be traced back to an internal leak in the automatic transmission fluid cooling exchanger, according to a recent post published via GM’s Techlink service site, which may allow transmission fluid to mix with the engine coolant. The cooling exchanger leak may result in a discolored engine coolant “with a strawberry milkshake appearance in the coolant reservoir,” GM says. If this happens, the coolant reservoir may also become overfilled to the point where the coolant is expelled from the overflow.
In addition, the engine may experience an overheating condition due to the lack of proper coolant, while there may also be possible degraded transmission performance, including a shudder and/or vibration. The driver information center may also indicate that the transmission fluid level is very low.
GM technicians are instructed to perform the repairs listed in Bulletin #08-07-30-035, which includes a transmission disassembly and the replacement of the automatic transmission fluid cooling exchanger. Technicians will also flush and replace the engine coolant system to remove the contaminated engine coolant.
This problem may affect certain examples of the 2021 and 2022 model-year full-size GM truck and SUV models equipped with either the turbocharged 2.7L I4 L3B gasoline engine or the 3.0L I6 LM2 turbo-diesel Duramax, and either the GM 10L80 ten-speed automatic transmission or GM 8L90 eight-speed automatic transmission. The following models are affected:
- Cadillac Escalade
- Cadillac Escalade ESV
- Chevy Silverado
- Chevy Tahoe
- Chevy Suburban
- GMC Sierra
- GMC Yukon
- GMC Yukon XL
GM has not issued a recall for this issue. Customers experiencing this problem should contact their dealership to have the above-mentioned repairs performed from Bulletin #08-07-30-035.
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Leaking tranny coolers have been an issue for a while in a number of different MFG products. It not only gets into the coolant but has caused shift and shudder issues in the transmissions. Audi went rounds with this.
My 2002 GMC Sierra with 262,000 miles has a trans cooler and guess what? Never have had any problems with leaking or strawberry milkshake.
How are your brake lines?
They are perfect. Thanks for asking.
Stainless steel brake lines are easy to install and last forever.
It’s not on the list. Sorry you missed that.
Or…. We could have an external tranny cooler, you know like used to be popular???? Better cooling, better reliability.
Eh, I had an external oil to water cooler on my old Cummins. It cracked open, fortunately just leaking coolant to the ground and not mixing. I don’t think there’s anything more reliable about it, just easier to replace if they fail
The more I look at these new vehicles, the more I start to appreciate the simplicity of my 03 3.4L Impala.
I cringe whenever I look under the hood of the newer vehicles and see the spaghetti bowl of pencil-thin vacuum and coolant hoses.
And the transmission cooler is built into the radiator – a much cheaper and quicker part to swap out if things go south.
I hear ya! I found a ’95 Roadmaster sedan with 35K original miles over a year ago. It’s now my daily driver. Proven platform, engine and transmission and no meaningless redundant electronic gizmos.
Oh good Lord
I am dealing with this problem on my 2006 Nissan Frontier and its going to cost $3000 for a transmission.
The Sierra is not on the list of affected vehicles.
Sierra or Silverado, same thing.
Yes Sierra is on the list. Read it again.
Oh, I missed it! There’s the Sierra. Looks like the V-6 and 6 speed transmissions are not on the list? Looks like they are not on there.
Isn’t TECHNOLOGY wonderful?
And it’s all for the good of the Manufacturer to sell more parts.
More GM problems !!
My father had a 1980 Buick with same problem. They fixed radiator and changed fluids. Car had 300k or 400k miles before odometer broke. No other engine or transmission problems. Interior petty much shot.
I bought two Toyota Avalons from a customer. Both have over 300,000 miles. Run great. It’s sad that these people buy these trucks and have this crap happen to them. I have 5 GM trucks all between 2004 and 2011. Not perfect but they do their job. Pink goo in the overflow tank 🤦🏻
LEXUS owners find all these GM problems amusing and wonder why people insist on buying them…Japan rules!!!!
Yep Wayno just like Honda’s problem of oil mixing with gas in CR-V’s no problem there just a blow engine or my friends 2011 RAV4 with low mileage that needed a new transmission my father also owned one with a slipping transmission, Tacoma’s that rust prematurely… But Japanese cars have no problems… YEAH RIGHT! Get out from under your rock ALL cars from any manufacturer have problems!
Have driven a Lexus Hybrid for 143,000 miles..only oil changes and runs like a Swiss watch. GM can never match this superiority. Keep sucking up to GM and they will reward you with valve lifter issue, missing high-end components, and premature aging for your hard-earned money. BTW, I have a life, and it drives just fine.
I have a Chevy Silverado with a little over 387,000 mile with only oil changes and an alternator replacement at 220,000 miles, no other issues. It has hauled a couple of broken down Toyota products to the mechanics shop on trailers in that time as well.
Japan doesn’t rule…most of these rust buckets are made in the US now. All vehicles are having issues not just those made in the US. My sister in laws Lexus need a new engine because of and I quote from the dealer, “a small issue with water and oil mixing in the engine”. Six months later no engine and no car and the dealer won’t lemon law the car since it is “fixable”.
Think airbags, gas and oil mix, brake lines coming apart, doors not fully closing and the list goes on for these fabulous Japanese cars.
Get a life.
No matter what, this should not happen. So GM has the forbidden Strawberry milkshake and Ford has the forbidden chocolate milk. These two domestic automakers need to do better.
A real mess that can shorten the life of all components affected. Especially if the all aluminum engine gets too hot.
Anyone making a investment in any vehicle is a big thing. Having them break causing financial distress is not good.
When will GM offer the mocha shake as an option for the anti-freeze vessel? Probably at additional cost, right?
That option is on back order. They will install the problem for $109.00
Fixable as long as the coolant doesn’t get inside the transmission. If it does, replacing the transmission is required. Happened to my 2003 Saab 9-3; GM replaced my transmission and radiator under warranty.
1995 Chevy 9c1 with 2501,000 miles. My summer daily driver. The oil and coolant and transmission perfect.