Radiator Fail

clt750

New member
Anybody out there have cross contamination between coolant and tranny fluid due to a stock radiator failing? I now have red coolant and murky tranny fluid.

The current radiator is of the stock variety and only about 5 years old.

Not sure how long this has been going on. I just went to check and add coolant last night and noticed the red. And its not from an off color coolant. I have only ever used the green type.

Havent noticed anything weird with the tranny as far as shifting either..... at least yet.

Thoughts?
 
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Yes, lots of us have had this. Don't use the green coolant. Flush the crap out of your transmission (flush until completely red/clear ATF drains out). Don't drive it at all. Get a new koyo or denso replacement radiator. Use the Toyota Long Life Red coolant. Hope for the best. That strawberry milkshake can ruin the transmission. The coolant is in the trans and destroys the clutch packs. Yo need all that coolnat out of the trans. Sorry this happened, five years is not that long.

Drive 100 miles and flush again.

No question you need a new radiator and lots of ATF. Get the cheap Dexron III for IV or the flush. Hope you can save the transmission.

Adding for OP...the original coolant is red, just FYI
 
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Do not drive the truck a single mile until you have the trans flushed the right way. Very common problem. If you catch it fast enough, you can save your trans.
 
It would be best to exchange that Milkshake out with Dexron Fluid II , III or higher. Most 4x4 hold close to 3 gallon of fluid. Like others have stated this is very common in radiators that are over 10-15 years old. Lots of threads on here about it.

The faster you get it out of there the better chances your transmission may survive it. Exchange the fluid twice.

It may already be damaged but with the cost of the fluid, its worth trying to save it.
 
"Don't use the green coolant"-there is nothing wrg with using green coolant

"It would be best to exchange that Milkshake out with Dexron Fluid II , III..." - why is it best to exchange the trans fluid with dex II or III, these r outdated trans fluid and there r any # off trans fluids on the market that far exceed property's of said...

"Get a new koyo or denso replacement radiator."- for just a little more u can get a nice all aluminium 3 row and not have to worry about the plastic top or bottom degrading over time...
 
Anybody out there have cross contamination between coolant and tranny fluid due to a stock radiator failing? I now have red coolant and murky tranny fluid.
Thoughts?
First, the correct coolant for your truck is red. It should be a deep, transparent red - much like transmission fluid only much more watery in consistency (and not oily).

If the coolant and transmission fluid mix, it looks like a pink milkshake. You can try to flush the transmission as much as you can (it is going to take a LOT of fluid to do it) to save it. You may be needing a new/rebuilt trans if you can't save it. Coolant in the transmission fluid degrades the transmission internal materials if it stays in there very long.

-Charlie
 
I'm curious as to how you caught this problem with cross contamination. Sounds like this could have happened yesterday or months ago.

You might consider scoping out a new transmission or a known good used one from a wrecked T4R just in case the flushing doesn't work.

I strongly suggest you use this method to replace all the fluid - twice; like others mentioned. Use the cheap stuff first just so you don't waste money, then if it's still working good in 50-100 miles, replace it with the better stuff if you like. Lots of people say the cheaper stuff is just fine as long as it meets Dexron II/III standards.

YouTube
 
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Lots of good advice on how to combat what happened. I would just add that I would flush, flush, and then flush some more. Your best bet to save your transmission is to get the coolant out as thoroughly as you can. I'd buy at least 9 gallons of cheap Dextron 3 ATF and run that through your system. Then, I'd finish the process with another 12 quarts of whatever chosen ATF you want to run. This will give you the best chance of saving your trans from an early death. Here's a video you can use for the flush procedure: YouTube
 
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Lots of good advice on how to combat what happened. I would just add that I would flush, flush, and then flush some more. Your best bet to save your transmission is to get the coolant out as thoroughly as you can. I'd buy at least 9 gallons of cheap Dextron 3 ATF and run that through your system. Then, I'd finish the process with another 12 quarts of whatever chosen ATF you want to run. This will give you the best chance of saving your trans from an early death. If you look through the sticky thread for videos you'll find a trans flush video you can use for this procedure.

When I had the Milkshake the dealer put 64 quarts through. Trans drove another 95,000 miles. In fact, theGipper may be driving on it still after he bought my wrecked 3rd gen. The key to longevity was lots of flushing and zero driving after contamination.
 
"It would be best to exchange that Milkshake out with Dexron Fluid II , III..." - why is it best to exchange the trans fluid with dex II or III, these r outdated trans fluid and there r any # off trans fluids on the market that far exceed property's of said...

You missed or higher Dexron fluids. It does state or higher. The transmission sticks state II or III. Stick with a dexron fluid as there are Techical Bulletins against putting Toyota Type T fluids in the 3rd gen transmission. As they are not compatible.


There are a pile of fluids that are dexron type equivalent to choose from.

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I agree with the others that state doing several exchanges to verify all the contaminated fluid is completely gone. Very good thought indeed. :-)
 
When I had the Milkshake the dealer put 64 quarts through. Trans drove another 95,000 miles. In fact, theGipper may be driving on it still after he bought my wrecked 3rd gen. The key to longevity was lots of flushing and zero driving after contamination.

I think I remember the Gipper having to finally replace his trans but I could be remembering wrong. But, running that much fluid through bought you a lot more miles so maybe the OP should buy 13 gallons of cheap ATF and 3 gallons of the preferred ATF he wants to run permanently in his trans.
 
"Don't use the green coolant"-there is nothing wrg with using green coolant

"It would be best to exchange that Milkshake out with Dexron Fluid II , III..." - why is it best to exchange the trans fluid with dex II or III, these r outdated trans fluid and there r any # off trans fluids on the market that far exceed property's of said...

"Get a new koyo or denso replacement radiator."- for just a little more u can get a nice all aluminium 3 row and not have to worry about the plastic top or bottom degrading over time...

1) Different coolants have different chemical properties and additives as well as different life spans. Toyota red is recommended because it came with toyota red. Standard green coolant can be used but will cause more corrosion than toyota red and will need to be replaced more often.

2) Dexron II (early 3rd gen's) or Dexron III (later 3rd gen's) is what was called for in the owner's manual. Some new transmission fluids are backwards compatible such as Dexron IV is listed as backward's compatible, but Toyota Type T is not due to extra additives that promote lubrication and cause Dexron II/III applications to have excessive clutch slip/wear. Just because newer fluids "exceed" the original properties doesn't make that a good thing.

3) The problem isn't the plastic portions, but rather the transmission fluid heat exchanger corroding in the radiator causing fluids to mix. To avoid this there are several options. Most people just replace radiator's more frequently as a precaution. Other people (myself included) bypass the in radiator transmission fluid heat exchanger for an external transmission cooler.
 
You missed or higher Dexron fluids. It does state or higher. The transmission sticks state II or III. Stick with a dexron fluid as there are Techical Bulletins against putting Toyota Type T fluids in the 3rd gen transmission. As they are not compatible.

Didn't miss the "or higher" I was specifically addressing the dex II and III part. the trans stick being as old as the vehicle states what was best when the vehicle was build but is completely outdated now and peeps just need to make sure the container of trans fluid they r using states it can be used in place of the aforementioned. Many fully synthetic that replace II and III can be bought 4 penny's over II and III specific.

Not trying to be an A^& or imply that u r unaware of anything I have said. I generally reply to post with the lay person in mind that will be reading this down the road. The way I read ur post was as saying "make sure the op gets fuild with Dex II or III on the front of the bottle" and was just trying to convey there r better options...
 
When I had the Milkshake the dealer put 64 quarts through. Trans drove another 95,000 miles. In fact, theGipper may be driving on it still after he bought my wrecked 3rd gen. The key to longevity was lots of flushing and zero driving after contamination.

Yup! The tranny now has about 215k miles on it and has zero issues.

The key is to flush the hell out of it, then flush it more. 3 months later, flush it again. 6 months later, replace the filter and make sure there isn't any brown clay buildup in the bottom of the pan.

Good luck
 
I'm curious as to how you caught this problem with cross contamination. Sounds like this could have happened yesterday or months ago.


YouTube

I was replacing a headlight and decided to go through a fluid check and noticed the coolant was red. I have never used red coolant only green mixed with water.

Then I checked the tranny dipstick and noticed it wasnt so much red but a murky brown.

And yes I could have been driving with it like that for weeks. I had no signs of any tranny issues or slipping.

Time and money have been a constraint the last few weeks so this weekend Im diving in.
 
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Then I checked the tranny dipstick and noticed it wasnt so much red but a murky brown.

And yes I could have been driving with it like that for weeks. I had no signs of any tranny issues or slipping....

All i know is this, if my trans fluid were Brown of any sort, I'd figure out how to afford buying even some wallymart trans fluid (it really is good stuff) and at least do a few drain/fills. Why chance it?

Luck and enjoy that Runner. :cowboy:
 
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I was replacing a headlight and decided to go through a fluid check and noticed the coolant was red. I have never used red coolant only green mixed with water.
The OEM engine coolant is red! You only have a mixing problem if the coolant is a milkshake-like pink.

Reddish brown trans fluid just means it is old and worn. It will also be red when new.

While I'm at it... Your power steering fluid is also red! (standard ATF, just like the transmission) If it is anything but red, it should also be changed out to a Dexron compatible ATF.

-Charlie
 

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