Radiator Replacement and tranny drain

[clt750]

2000 3.4 220K plus mileage

So I posted up a few weeks back that Im getting cross contamination between coolant and tranny fluid. Ive been assembling some of the items to start the radiator replacement and tranny drain but Im a little miffed on where to start.

Obviously I want to do a coolant flush, and want to do it before installing the new radiator, thermostat, hoses etc. Id like to remove any coolant/tranny fluid mix before the new rad goes in. But since there is a leak between the 2 systems can I disconnect and temporarily cap the tranny lines so I can run the engine to do the flush? Do the coolant flush and radiator and then re install tranny lines to new radiator? Is that a suitable idea until the new radiator is installed, or bad idea? OR...... can I just leave the lines free while flushing the tranny out and let the fluid drain into a pan?

I mean..... I want to have the new radiator in so I can start a tranny flush right? How much should I be concerned on what gets done first?

Im just looking for the best way to do this without having to do something twice....... and crossed fingers its done right.

Thanks in advance
Curt

 

[thezentree]

I haven’t ever done that, but I would imagine that you’d want to plumb the two tranny cooler lines together. Otherwise you’re going to pump fluid out through the trans cooler send line while starving the trans of fluid because there’s nothing coming in the return.

 

[Brian.]

The transmission lines (feed and return) connect to the bottom of the radiator with 3/8" flex lines. Get a double-ended 3/8" connector like this:

and remove the radiator from the equation. Or, if you're going to install an extra, external, ATF filter you could just use that. You do not want to "plug" the transmission lines, though you may need to plug the trans cooler ports on the radiator, depending on how bad of a leak you have.

Steps I'd take are the above to remove the transmission cooler, then multiple coolant flushes before replacing the radiator and moving onto the transmission. Timmy has videos on both the coolant and the trnamission flushes.

YouTube

YouTube

 

[BoomerBob]

It was already covered on how to connect the return lines together but one other thing you might consider besides completely flushing the transmission a few times with cheap trans fluid like what Walmart carries which is good fluid; just cheaper in price than most.

Replace the thermostat but put the housing back on before installing the new one so when you start the engine to flush it; it won't have to warm up enough to open the thermostat. Just keep using distilled water ($.80 a gal at Walmart) to flush the radiator and engine several times until it looks clear enough. Then after you pull the old radiator, install the new thermostat while you have more room, then install the new radiator.

I personally chose to bypass the radiator for trans cooling and installed a Hayden 678 trans cooler. If you do install a trans cooler; install it before you install the radiator so you can always remove the radiator without having to cut the trans cooler mounting ties. They will then be in front of the radiator mounted to the AC condenser.

 

[clt750]

Things were going decent while taking everything apart, but I have an aftermarket TRD Supercharger. There is a pulley in the way of getting to the top thermostat housing bolt. Ugh. Not sure on how to remove this to get to that housing bolt.

I ran it through several cycles to drain the coolant through the radiator drain plug and then pulled the old radiator and hoses, but still don't think its 100% clean.

If I can get this Supercharger pulley removed and thermostat housing off can I run it with no radiator by putting a hose in the top inlet and just let it blow out the bottom with no radiator?

 

[Bad Luck]

Things were going decent while taking everything apart, but I have an aftermarket TRD Supercharger. There is a pulley in the way of getting to the top thermostat housing bolt. Ugh. Not sure on how to remove this to get to that housing bolt.

I ran it through several cycles to drain the coolant through the radiator drain plug and then pulled the old radiator and hoses, but still don't think its 100% clean.

If I can get this Supercharger pulley removed and thermostat housing off can I run it with no radiator by putting a hose in the top inlet and just let it blow out the bottom with no radiator?

You can, but I would flush it a couple times after that with distilled water to make sure all the tap water is out of the system. You don't want any lingering tap water in your system if possible. Tap water has a lot more minerals in it than distilled water and cause corrosion in the system if there is too much.

 

[3bears]

on the tranny return line...doesn't that just dump into the tranny pan ?
when doing the flush like MTBTM does ( and I do that way now) no fluid is going back to the return line anyway...right ?
So I would think you could flush the tranny the MTBTM way using the inlet line to radiator.., capped or disconnected return line.

Sounds like you might not be able to pull your thermostat easily for flushing the engine...but I would try to, then replace with a new TOYOTA thermostat when done..dont forget jiggle valve at 6.

you could flush with tap water a few times to get all the tranny yuck out of block...then many many times with distilled water...or flush from the start with distilled water

then TOYOTA or Asian red antifreeze...no green stuff.

also a new TOYTOA rad cap

cross your fingers...it can work out good if you did not go too long on the milkshake......I know...my 4runner is a milkshake survivor.. ( happened to previous owner..I did not know at time I bought it..till I saw dealer service records weeks after...repair done at dealer...went in drivability issue..tranny and cooling flush and new radiator....to me...that was a milkshake fix) 8ok since ( plus several flushes, magnafine filter and running synthetics and another radiator as preventative a short time ago)

 

[gamefreakgc]

Things were going decent while taking everything apart, but I have an aftermarket TRD Supercharger. There is a pulley in the way of getting to the top thermostat housing bolt. Ugh. Not sure on how to remove this to get to that housing bolt.

I ran it through several cycles to drain the coolant through the radiator drain plug and then pulled the old radiator and hoses, but still don't think its 100% clean.

If I can get this Supercharger pulley removed and thermostat housing off can I run it with no radiator by putting a hose in the top inlet and just let it blow out the bottom with no radiator?

There's a drain plug on the block itself to drain the engine without removing the thermostat. I don't remember where but that will solve your pulley issue.

A little oil in the radiator is more acceptable than water in the transmission. Water will kill the transmission but oil can be flushed out over time in the engine. I think your flush attempts will be sufficient, can also find that drain plug on the block.