In general liquid to liquid heat exchangers do work better than air to liquid heat exchangers, but it all depends on the coolant temp to ATF temp delta. My coolant runs hotter than my ATF temp most of the time so if I was using a radiator ATF cooler it would actually increase my ATF temps.

 

X2. The coolant in the rad (even near the outlet) is always hotter than the ambient air temperature, and delta T has the biggest effect on HX efficiency.

 

1) Then does the rad actually help warm up a transmission during cold weather and actually help it?

2) it does seem like I have read about quite a few of failures on YT lately!

 

do a power flush, change the radiator, use some of that lucas transmission fix stuff in the tranny for the time being until your situation improves (if you're in a tight spot). then when it goes you can convert to 5 speed! wont have that problem, and you'll have more power! sucks to hear though bro, good luck! power flush the hell out of it.

 

https://www.yotatech.com/50638430-post10.html

https://www.yotatech.com/50694832-post33.html

https://www.yotatech.com/50695192-post35.html

 

Leak internally?
The leak is between coolant and ATF. If you only have coolant running through a radiator, the leakage into the trans cooler section is not an issue.

There aren't many complaints about the rad leaking externally, so makes no sense to replace what's not broken. You want the rad to keep coolant in, that's it.

 

As we all agree, the radiator is shot. The trans cooler that is inside the radiator cracked and allowed the trans to pump the fluid into the radiator which puked everywhere.

I would replace the radiator. Top off the trans. and drive it to a shop. Have a good shop power flush the trans. Drive it for a while and have it flushed again. If that doesn't work then have it rebuilt.

Better yet. Replace the radiator. Then call a good trans shop and see what they suggest.

 

Be specific... we don't all agree that the radiator is shot... but we all agree that the tranny cooler portion of the radiator is shot.

As mentioned previously, flushing the tranny cooler and short circuiting the tranny cooler ports on the radiator with a hose will provide him with a perfectly functioning radiator.

 

X3, I'd keep the radiator. Just bypass the ATF cooler part of it and flush the cooling system out.

 

I see you have been fiddling with this. (Maybe I shouldn't complain about my 5sp anymore)

 

Everything has is own problems. You get to mess with the clutch

 

Hey good post, I operate my truck in the winter time, I'm sure 90F to 140 F is perfectly fine temp for the trans fluid to operate at right?

Any issue with the bypassed ATF line causing low ATF temps in the winter? (for the time being, without being hooked up yet to the cooler)?

Thanks

 

That's a good question. I'm really not sure but like I said my BMW came from the factory like that (no radiator ATF cooler just a seperate cooler in front of the radiator).

I've had no issues yet but we don't have very bad winters here. I'd be sure to get a cooler with a built-in bypass for cold temps. Like the ones from IPT here http://www.importperformancetrans.com/coolers.shtml

 

i live in az and i plan to do towing in the summer time so i am looking at the 4739 the biggest one.

i dont think that i will ever be to cold here in az

 

It sounds like you have aspirations of running no cooler at all for the tranny in the winter. I would advise against that. Going up long hills generates a lot of heat in the torque converter, you could end up frying your tranny (even in the winter). The aux coolers are pretty cheap and you are going to eventually get one anyway so go ahead and put one on now. You've already traumatized the tranny with the liquid milkshake so don't turn around and fry it by not having a cooler.

 

My bad. Thanks for the correction.

I guess I should have said that if you want to fix it back to the way the manufacturer built it you would need to replace the radiator. It sounds like bypassing the cooler in the radiator works just fine.

I would agree that you should get a cooler on there.

 

Me 3, just covering the air flow on half of my ATF cooler got my ATF temp up to 175* F with the ambient temps in the high 30s F.

BTW have I mentioned how nice it is to have a tranny temp gauge?

 

No $h!t (suck in traffic, bushing cracking, stiff pedal movement, squeak, wife hates it - oh well)

 

Well guys,
After pulling the 4 runner into my home's garage today I had a chance to look things over...Drained the Coolant and It showed a nasty mix of red Trans Fluid and Red Coolant...no big surprise which I knew was the case already...

AND NOW FOR THE $3500.00 question??? and that question whether or not the coolant water combo mixed fully into my transmission...?
Now, as I worked the trans plug loose, I crossed my fingers and prayed that there wouldent be any coolant in my transmission pan...
HERE IT GOES: Drum roll .....Drum roll...drum roll


All I have to say is: WTF ATF!! WTF ATF!! WTF ATF!! pure FREAK'IN milkshake....
I am screwed

Well what do they say? The "hope springs eternal".

1st step I will bypass the trans line and begin the flushing process...My guess is that the transmission is cooked, maybe a 5% chance my trans is ok... The only saving grace is that I shut it off right away. Like I said maybe 1 in 20 chance....
Here is likely what I'm looking at
1) new or rebuilt transmission
2) tons of coolant and water mix for the cooling system flush
3) gallons and gallons of cheap ATF for my futile attempt to save my trans through crazy flushing...(like I said 1 in 20 chance)
and then if I run enough of the milk shake out I will put in the good DEX III
in and try to drive it...YIKES

4) A new radiator ...might as well, a good after market is about 175.00 ( oem is over $500.00)

5) a ton of time going back and forth to auto zone to recycle the "flushed" coolant and ATF Mix...they (auto zone) likely will not want the "contaminated milkshake combo" and refuse my humble offer to recycle, (and I can't say that I would blame them...)

well well well, time to start saving for a new trans.
great day for the icerunner... ROCK ON.. YEE HAH!!

 

Well, the foam that was circulating through the transmission does a poor job of maintaining pressure so that will cause the tranny to slip. The foam also does a poor job of lubricating which can lead to parts failure. Hopefully the tranny was slipping prior to the self-destruction process beginning.