2002 4runner radiator/head gasket issues

[maxthedog]

Have a 2002 4runner SR5 Sport with about 175K miles. Looking for advice -

In Dec. started spewing foam - was told transmission cooler ruptured into radiator mixing antifreeze/transmission fluid. Replaced radiator, flushed transmission and coolant. Eventually replaced hoses. 7 months later started overheating and losing antifreeze. Dealer says original failure gummed up engine block, causing lack of coolant, head gasket failure etc, never mind that it happened a day after dealer serviced it.

Basically says transmission is questionable, although it's gone 7 months no issues, and head gasket need to be replaced at a minimum + probably other engine damage. Looking for feedback on whether it's worth trying to salvage. Otherwise it's in decent shape for 175K miles.

The original problems seems like a pretty horrible design flaw, interested to know if anyone else ran into this, or thoughts on why it might happen other than just bad luck - the vehicle has been serviced like clockwork...

[kball]

The OEM cooler built into the radiator is a very common setup with many makes of cars. It does fail however and since these 4runners last so long the chances of it happening sooner or later are great. It has happened to a lot of people. Search the internet you will find many links. Search for "strawberrry milkshake" "pink milkshake". The dealer actually calls it the pepto bismal problem. Everyone reading this, please bypass that OEM cooler and install an aftermarket trans cooler if you have over 100,000 miles on your truck! Some people replace the radiator which is fine and should give you another 100,000 miles of trouble free running. I just never wanted to take the chance. I bought my runner with 176K on it and bypassed the OEM built in radiator cooler right away. Here's some links.

http://www.toyota-4runner.org/3rd-ge...milkshake.html

http://www.yotatech.com/f2/strawberr...48/index3.html

http://www.yotatech.com/f2/bypass-oe...cooler-126953/

How did the dealer fix it originially? Did they just flush the trans and engine coolant system and put in a new radiator? You say the trans is basically fine so I would not worry about it at this point. After the milkshake it could go anytime but you've gone 7 months and it seems to be fine so I'm thinking you got it taken care of quickly enough so there was no real damage to the trans. You say the engine is overheating again and "foaming"? Is it another milkshake? Or is it just coolant foaming?

[maxthedog]

Thanks for the links... too bad I didn't see these a year ago...

So the dealer flushed the transmission with about 20 gallons of transmission fluid, flushed the coolant. replaced the radiator,. Eventually also replaced the radiator hoses and the radiator cap when they started leaking.

Unfortunately ,I wasn't driving it and circumstances are such that I haven't seen it yet. From what I've been told, it was leaking coolant, not the pink foam again, but it was blowing white smoke and overheating, which does sound like a blown head gasket.

However common it may be, I still think it's a horrible design flaw. At a minimum Toyota should at least recommend as part of standard service what was suggested here - replace the radiator at 100K or so. A minor price to pay.

So with 7 months and probably 10K miles the transmission is probably not going to be a problem?

[kball]

Head gaskets blowing on the 3.4 engine aren't too common but after overheating before with the milkshake you never know...

After coolant gets into the trans everything is up in the air. You've gone quite a while and put some miles on it so hopefully you caught it in time before the coolant ate away at the trans internals. It's not the water that causes the problem it's the actual coolant that eats up the seals and clutches.