Help me before I mess up. Radiator, transmission and more

Hey members, before anyone says to search within the forum, I have been reading different ways, ideas, suggestions and opinions as to the whole strawberry milkshake thing. I just need some clarity as to what to do first and how to go about it. I know and understand that there will be conflicting opinions and such but I will more than likely go the way of the masses. You know, the majority. Ok here I go.
I have a 2000 Limited w/278K on the clock. 2nd owner. 1st owner kept pretty good records of maintenance. The trans and cooling system has been flushed about 4-6yrs ago from what the records showed.
3 days ago I was pulling out of the convenience store and my truck accelerated slow and wouldn't go past 30mph though it revved as if it were going faster. I immediately pulled over and was baffled. I get out and look around the truck, thinking that I might have a flat or something. Nope, nothing wrong w/the tires. I get back in, start her up and everything is fine. I put her in gear and nothing. I tried R, D, D2 and nothing. Like it was in neutral. I turn it off, get out and lift the hood and my coolant reservoir's cap is off, drivers side of engine bay is soaked. Now mind you, a day or two before this I noticed my res tank was a little low and I filled it w/basic 50/50 coolant(green), and yes I know, its not the right kind now but didn't before.
Call a tow, get it home and the next morning I look at it again and add a bit of distilled water. Like lil less than 1/2gal. Put it in the res, and started her up. Put it in drive and it went. I only drove around the block and parked it again. Look under the hood and took off the rad cap and there is nothing but a reddish brown slurry around the inside of the cap. Checked the res and the black tube dripped the same thing. Checked the tranny stick and the same.
Ok, I have a radiator, trans filter, atf and toyota coolant on the way. My questions are:
1) Do I flush the rad or the tranny 1st?
2) If rad is 1st, do I disconnect the tranny lines?
3) If rad is 1st, do I flush it with old rad still installed and connected?
4) It tran is 1st, do I drain it 1st via tran plug or the hoses that go to rad?
Any and all help would be greatly appreciated. Thank you

 

So, what's done is done...and you may as well try and see if the tranny can be saved.

I assume you are flushing this yourself?

If it were me:

Drain the old radiator.
Disconnect the transmission lines to the rad, let them drain.
Remove the radiator.
Pull the drain plug on the transmission pan and drain it.
Remove the pan, I guess...not sure if it's any use to change the filter now.
Put in the new radiator. Fill it with just water (distilled...for now)

Go on youtube and watch how to change the ATF fluid using the fill/drain/fill dance. You have like 12quarts of atf/coolant in your torque converter that needs to be flushed out. The whole system takes like 16quarts of ATF. Put about 2 quarts of fresh ATF in the transmission filler on the top of the engine, run the car for a bit with the tranny hose disconnected and draining to a bucket. After 2 quarts drains, fill 2 more quarts, drain 2 more, etc until the atf comes out cherry red. May take you 24+ quarts of the stuff. *Not sure if this will do more harm than good*. You may want to go straight to a transmission shop or mechanic and see if they can do a flush with their machine.

Drain the water and whatever it cleaned out of the engine and put in pre-mixed yellow coolant. I don't feel anything left in the engine by the old radiator failing will hurt the new radiator.

Pray the transmission works again.

 

well waiting for the radiator, trans filter, gasket and rad cap in the mail. flushed tran w/3 jugs of atf fluid and now is a light strawberry color. prob will need another 3 jugs

 

thanks guys

 

So you flushed it with the broken radiator still in the car? If so, why? Won't it just refill the transmission with coolant? How did you do the flush?

 

Yeah but it is disconnected from the radiator. I removed the 2 small hoses that are at the bottom. everytime 2 quarts of trans stuff pumps out, I replace w/ 2 quarts of new clean fluid and I used 3 of the gallon jugs doing this. Now its freaking raining and its holding up my progress, lol

 

Got it.

Hope the transmission isn't toast. Keep us posted.

 

hoping for the best outcome...

 

For those who may be following, who may have read and especially for those who had helped me, here is the updates.

Eng. Cooling Sys:
ok, new rad installed, flushed engine w/dis. water (6gal total). Replaced the thermostat. Put almost 3 jugs of napa asian red/pink coolant in. There was like a chocolate milkshake color, not texture but color so i performed two flushes using that prestone cleaner stuff. and also flushed without thermostat installed.
Trans:
Replaced trans filter and gasket. B4 that I manually flushed trans with about 32-36qts of trans fluid. Its still not as clear as new fluid but its way way far from looking like how the milkshake was. Here is what I would like to know:
1) If trans uses Dex3(H), can you use this to just flush the bad fluid out but replace the final fluid that you will use while driving with the toyota brand or whatever? Reason I am asking is because of cost and amount. It is easier and more efficient cost and size wise to get a 5gal or more instead of buying the whole shelf at WM. What do you guys think?
https://www.walmart.com/ip/Multi-ve...-007-1789437688cf03&athancid=null&athena=true
Also my drain plug is leaking and noticed upon removal of drain plug that it is stripped. It goes into pan and stays but still drips.
What is the size of the plug anyway?
Is it the same as the oil drain plug?
Could I use a rubber grommet as a temporary fix?
Lastly I noticed that where my brake line goes into my drivers side caliper has a slow leak. this is something new. Last year b4 covid, I replaced rotor's, pads, calipers with the larger upgrade but not the biggest ones. Forget what size actually, but you have the factory size, then the size I choose (maybe 199mm?) and then theres the 231mm. Anyway any suggestions as to how

to correct the problem or diagnosis it?
thanks in adv brothers

 

My oil pan drain bolt gasket disintegrated. So I used a little white Teflon tape near the head and seems to be holding up...,,

 

the gasket? if you meant to say drain plug, then thats a pretty good idea. thanks

 

I just realized that and changed it. I never proof read.,,,