I've been battling the corroded freeze out plugs behind the tranny for a few years now.
Last time i added good ole stop leak....the stock rad plugged up.
No biggie..... To bypass a possible strawberry milkshake issue, i Replaced it with an aftermarket and filled it with red toyota antifreeze.l
Been fine for about a year and a half but the minor leak is back.
My question is..... Has anyone ever added stop leak and made a bypass tube to connect the 2 hoses and bypass the rad or have a recommendation for a good stop leak?

Yea.... Had intentions of pulling the tranny but it looks like a complete ball buster job.
With gas at 4 bucks.....the runner rarely gets driven anyhoo.
Just wondering......kenny s

 

Are failing freeze plugs common on these engines? If so, what's the root cause?


Andreas

 

I've never heard a bottled stop-leak story that had a happy ending (typically costing as much or more in the end to right everything). If it were me, I would either keep driving it and topping off the fluid or fix it properly.

 

^^^this..there have been a couple recent examples of the damage products like stop leak cause.

 

Those^^, stop-leak is evil stuff.

It's only use is extending the life of an engine just a little further before replacing it. You can pretty much wave goodby to an engine with that stuff in it sooner or later.

 

Using standard coolant in a 3rd gen 4 runner will cause
internal corrosion over time
the steel freeze out plugs for example.
Has to do with silicates in the antifreeze.
Red toyota antifreeze is formulated to prevent
internal corrosion.
I did not know this until a mysterious leak
appeared behind my trans bell housing.
How is radiator stop leak going to kill my engine?
I know it will clog things like heater cores and rads and thats
why i used it right before replacing
the stock milkshake radiator.
I'm not referrring to any form of engine oil stop leak.

Kenny s

 

It will also clog the coolant passages inside the engine, while not as deadly as oil stop leak it can still very much cause the same kind of issues. It can also kill the water pump/clog it up ect.

 

Stop leak is a bandaid that does not address the main problem. It creates more problems than the inital one and it may not do what it claims it will do. If you have to bypass something inorder for it to not do harm, what is it doing to the rest of the engine?

Keep topping off the fluid and change the actual problem when time and money allows. It really is a no brainer

 

When I was working for Subaru, a car was brought in for HG replacement, I took it all apart and unbolted the heads and the heads would not come off, I had to hit on it with a rubber mallet for about 10 minutes before it gave loose. The stuff holding it together was stop leak, the coolant passages were all gunked up with the stuff and eventually they had to just buy a used engine.

If all this stuff actually worked the way they say it does, I would be out of a job since everybody would be adding this snake oil to their cars to fix it. You think a transmission is a tough job, sooner or later you will be doing an engine instead.

 

No doubt....... An ounce of knowledge in this case can be dangerous to an engines health.
I'm no noob to mechanics or 4runner issues....... Just not ready to dig into the jigsaw puzzle that is transmission removal.
I'm sure people have dumped numerous doses that stuff thinking more is better.
Kenny s

 

The fan on my '90 grenaded a few years ago and put a few pinholes in my brand new radiator. Not about to buy another radiator, I cracked an egg in it (much less lethal than stop-leak) while cold and then warmed it up to slowly cook the egg. Before the nay-sayers chime in, it hasn't leaked a drop for over 2 years and there were no ill side-effects. Now, I know it's not the best idea, and I need to solder the pinholes eventually, but it might be worth a shot if you're just looking for a temp fix.

 

I have seen this before as a temp fix, never seen anyone use it long term though.

 

I know, I need to get in there and fix it the right way but it's held great so far. I would definitely not recommend it as a long term fix.

 

The egg trick... I have used it before, and it does works, but 2 years??? Anyway... I would certainly use the egg over any "stop-leak" stuff, that stuff is just horrible to a motor! If ur gonna use the stop leak, or my personal favorite "blue devil" U might as welll just be pouring super glue in....

 

Just goes to show that it can work pretty well. I DD that rig too. I'm well aware that two years is way too long for any temp fix, especially egg in the rad lol, but it's holding up great and to be honest I just keep forgetting about it.

 

Lol..... 1 egg coming up........gonna give dat a go! Ha ha!! Thanks

 

I still don't get it, you say you never drive the truck and that you are a capable mechanic, why not just pull the tranny and fix it right, doesn't take that long and pulling a trans is a pretty straight forward job that isn't hard to do at all.

 

It will get done.... Someday!
In the meantime......i've got a tip for future egg droppers....... Mix the yolk because dat baby aint gonna slide into the little runner spout!!!
It jumped out , slid down the fan shroud , through the skid plate and on to the floor!
Ha ha!! Funny stuff!!
Kenny s