I've read about the strawberry milkshake problem with the gen 3 4Runners for a while on here. As a result, I planned to get a Koyo A1998 radiator about a year ago but never got around to it. You can guess where this is going...

I have 116,000 miles on the truck and had returned from a 200 mile drive the day before. Next day, Monday Aug 30, I head to work and 4 miles into the drive steam pours from under the hood. I pull over immedatly and shut her down. Bad thoughts are brewing. I gather the courage to look in the coolant overflow reservor. I see foamy pink fluid and I knew what happened.

I had the truck towed to the dealer and they confirmed the trans cooler failure. The fluids mixed in radiator and spread into the engine and transmission. As we know, the engine is not such a concern but the contaminated trans is.

I hope that becasue the trans did not overheat it can be saved. We'll see. I had a new Koyo Radiator installed, an engine coolant flush and trany flush. They actually ran 60 quarts of synthtic blend through it, I know $$$$ but I give them a pass because they didn't know it was going to take that many quarts when they started. They ran new trans fluid thrugh the system until no pink foam or water was comming out.

So far the trans runs fine but every story I've read on here ends the same, trans replacement. We'll see....

Point of the post is just to document another Gen 3 trans cooler fail. And to let you know the trans overheating light never came on. Radiator failure was the indicator. So far so good, but I'm only two weeks in. Actually, it drives better now, I think.

 

Did you drop the pan and change the filter? I am hoping your seals make it for the long term.

Sorry to hear of another milkshake story. PM is the way to go to hedge against this problem.

It funny to see all the engine bay shots of 3 gen 4 runners on Ebay and to see some of them with new radiators and hoses, yet no mention in the description of engine coolant being dumped into the transmission.

 

How much is the Koyo and what site has good prices for one so i can ask Santa for one before I'm struck with the milkshake?

 

I did not drop the filter, good idea. I can handle that myself. I was told the filter is a lifetime part but probally not after the trans cooler fail.


I paid $198 through the dealer for the Koyo A1998. So far it looks like a good replacement. It's very similar to the factory part in appearance. I planned to buy from here until I was caught off gaurd.

http://www.go-part.com/9602-toyota-4...src=googlebase

Or ebay is an option

 

sorry to hear badattitude. i got my koyo thru ebay for 12x.xx shipped i think. its sold thru go part on ebay but its cheaper for some reason on ebay.

 

Does anyone know if there is a mileage threshold that would indicate the trans will be ok. For example, if I can get past another 20,000 am I "out of the woods so to speak" regarding trans failure?

Driving around wondering when/if I'll get stuck on the side of the road due to transmission failure is no fun. Kepping my fingers crossed.

 

With even possible slight damage it's impossible to tell how long the tranny will last and I wouldn't say you are out of the woods as it just might wear out sooner than a tranny that has had no issues.

You have 116k now on the tranny so it's got a little wear on it and if the flush really cleaned it out you could see another 100k from it of it could fail in 10k miles but if you get past that 10k mile mark I think you'll be fine for extended miles but might simply experience more than average wear thus needing a rebuild/replacement sooner.

Good luck and let us know how the tranny is doing since I don't recall too many "pink milkshakes" stories ending with a working tranny.

 

so replacing the radiator with the ones above will prevent this problem? or would getting a new/different trans cooler be the way to go?

 

Some people go with either an external trans cooler or an OEM replacement;the thing I've heard about sticking with OEM is it's factory reliable and it's more efficient in stop and go or crawling along a trail and will lasy at least another 10 years but on the other hand an external ensures your coolant and trans fluid will never meet.

 

Thanks for the feedback

Yea, not too many sucsess stories, I recall "save the money for the flush and just get a new/used trans" in one of the threads I read. I will post if/when it fails. Hopefully the fact it didn't overheat is positive.

Oh yea, I tow a boat sometimes

I still think this is fantastic truck. I'll say this is one of the best built trucks I've owned. I've had no other problems.

I think either the external trans cooler or a new radiator are equally as good at preventing this, just got to catch it in time, no procrastinating like me. Also, the koyo A1998 is the only non toyota radiator I would personally consider. I heard good reviews, and so far my personal experiance is good as well.

 

BA, that's a bummer to hear on the pink milkshake! Glad you got it fixed as quick as you did. I agree though, it's very rare to see the flushed tranny make it past 10K miles. Hope that's not your case...


Very true. Anyone interested, just search ebay for "KOYO Radiator A1998". This one's not but $106.00: Click Me

 

Badattitude,
thanks for sharing the information about yet another milkshake issue. The new radiator and tranny cooler moved up the list a few notches.

And to anyone else considering a new radiator and/or external transmission cooler. A while back I had found nice deals on both of those items.

96-02 Toyota 4Runner KOYO Radiator A1998 $137.95

Tru-Cool LPD thin 4454 $54.02

Hope that helps.

 

The radiator is fine. Why replace it?

 

transmission survival after milkshake depends on

dropping the pan and filter
and hosing everything out with ATF and a tranny machine until the stuff dribbling
out is clean. then install filter and new pan and use the tranny machine to pump
about 45 quarts of ATF through it.

if you do not drop the pan and change the filter, water WILL collect around the valve
bodies and solenoids and start rusting things....not good. you cannot get all the water
out if you do not drop the pan and toss the filter.

and yes it is still a crap shoot after that...but there are those who have survived the milkshake
and gotten 100,000 + more miles out of it.

 

I can't believe that happened with only 116k on your truck. I guess it has more to do with time than with mileage? Although I've got a '99 with 172k and no milkshake, though I've put in an external cooler now to make sure it won't happen. Still, 116k seems very early for this failure to be happening.

 

Yea, 116,000 is early and I agree it's an age related problem more than a mileage one. This truck has been well cared for. I should also note the coolant was flushed with Toyota red at 79,000 miles. So changing the coolant on time doesn’t do much to prevent this. At least in my experience.

Thanks the filter advice BigBalls. The filter was not dropped and I'll make sure that I get it out of there. I already had 60 quarts pumped though with the tranny machine. The mechanic said absolutely no more water was in the residual fluid. But to be safe I think I'll flush once more when I change the trans filter.

 

1) My 4runner was always serviced by the dealer at the recommended intervals,
and of course the 3 timing belt changes means full rad flush each time. milkshake still got me. it has nothing to do with maintenance it is time-based

2) yeah the ATF will show up clean because no more water is coming out, but
there is still water in there stuck. really only a 100% tranny rebuild will be the for sure method.

but water gets trapped in the filter and around the solenoids... so it makes sense to do as much as possible. and that means drop pan, force ATF in through the ATF cooling lines until nothing but ATF pukes out, then install new filter and attach pan, and then pump the next 45 quarts via the lines on a tranny machine.

 

What replacement radiator is a good option???

 

With all of these strawberry milkshakes being reported, what - if anything - is Toyota saying about the issue?

 

The two dealers in my town both say they never see this. And "if you change your coolant at the recommend intervals it won't be a problem".

It's a design flaw, it happens, but I wish toyota would at least encourage people to replace the radiator/trans cooler as part of regular maintance. I mentioned my concern about the potential trans cooler failure and it was downplayed as a non-issue. well we know that is not the case.