Has "pink milkshake" ever occurred in a newer Toyo radiator?

[dbsoundman]

Has anyone actually experienced coolant and ATF mixing while using a newer Toyo or similar radiator in their 4Runner? I feel like this is the definitive answer to all this discussion about transmission coolers and routing. I'm not sure that any of these radiators are really old enough to judge this adequately, but I figured it would be worth asking the question. Or, alternatively, does anyone know what exactly causes the pink milkshake in the original radiators, and what might be different about the Toyos that would prevent that from happening?

 

[blizz86]

Has anyone actually experienced coolant and ATF mixing while using a newer Toyo or similar radiator in their 4Runner? I feel like this is the definitive answer to all this discussion about transmission coolers and routing. I'm not sure that any of these radiators are really old enough to judge this adequately, but I figured it would be worth asking the question. Or, alternatively, does anyone know what exactly causes the pink milkshake in the original radiators, and what might be different about the Toyos that would prevent that from happening?

From what ive read: it happens when the radiator corrodes, and thus pink milkshake.

Use good anti-corrosive coolant (toyota's red coolant) and replace your radiator is you can see corrosion through the coolant fill cap. good to go!

 

[Kung]

Nope.

 

[dbsoundman]

From what ive read: it happens when the radiator corrodes, and thus pink milkshake.

Use good anti-corrosive coolant (toyota's red coolant) and replace your radiator is you can see corrosion through the coolant fill cap. good to go!

Interesting, so this suggests that people who get pink milkshake tend to use non-Toyota coolant as well.

 

[Drcoffee]

The search function works fairly well here. But for a better understanding of the tranny cooler within the radiator take a look at the picture below.

The mass of the cooler is inside. The ports are threaded and made of aluminum. The threads (inside the radiator) is where the break occurs. Its unseen until its too late. The coolant and trans fluid will mix quickly because the radiator is under pressure when hot. Something on the lines of 12-15 psi. So once the port cracks, the coolant will be forced into the transmission fluid path and mix together.

So why is this radiator more prone to breakage than your typical sedan? Good question, I'm glad you asked. On a typical sedan, the radiator has 4 doughnut rubber isolators (one at each corner) to absorb vibrations and shocks. So when you hit road imperfections, the radiator is buffered from the shock.

Now lets look at the 4runner radiator. It has a steel frame integrated into the radiator which is directly bolted (4 bolts) to the radiator surround which is essentially part of the frame of the truck. So each time you hit a bump in the road, the shock is transferred directly to the radiator and to the internal transmission cooler. That tranny cooler inside is vibrated at the threaded port and aluminum hates vibration. Over time it will fracture and break.

What factors contribute to breakage? Great question. If the coolant isn't maintained properly, aluminum will corrode weakening the metal. Add daily vibrations and shocks and over time the ports slowly weaken.

Replacing the radiator is the only fix for the problem.

 

[blizz86]

Good information above. There was also a post a few days ago about the electrolysis (again corrosion) of the aluminum in the radiator having to do with ionized coolant and the cars electrical system but i dont remember many of the details.
You should be clear with good coolant and a new radiator. Also if you buy toyota make sure to distinguish between concentrated and premixed lol.

 

[dbsoundman]

So does the Toyo radiator have the same issues with shock absorption that the stock Toyota one does?

EDIT: OK, so based on the above, it would fundamentally have the same problem, since it's an issue of the shock absorption of the radiator and not an internal component fault. The next question I would then ask is could the stock radiator be mechanically isolated via rubber grommets or some other means?

 

[blizz86]

So does the Toyo radiator have the same issues with shock absorption that the stock Toyota one does?

EDIT: OK, so based on the above, it would fundamentally have the same problem, since it's an issue of the shock absorption of the radiator and not an internal component fault. The next question I would then ask is could the stock radiator be mechanically isolated via rubber grommets or some other means?

I would say you shouldn't worry about dampening any vibrations to the radiator as much as maintaining the coolant and checking to see if there is any corrosion currently present in your radiator. Thats where the real issue is.

 

[zgensler31]

To eliminate the pink mikshake issue there is another option. You can stop using the stock tranny cooler and cool your atf using an external cooler. I'm not saying this is the way you should go or the best way as there are a lot of things to consider before making this change. Things like how will using an external cooler(whichever one may choose) affect the temp of the atf fluid. Will it cool enough or too much? Will it warm up enough and in a reasonable amount of time?

These things have been discussed numerous times and there are a number of threads on the topic. This thread is not about tranny coolers so I don't want to stray too far off topic. Just wanted to make sure you knew that eliminating the issue is an option.

 

[zooroadbaja]

Mods need to make a sticky about this radiator, B&M situation. Way to many post in the past few days about this.