Bastor

Hello guys,

We recently picked up a 2006 GX 470 and tossed it in the shop to have the oils, cooling, timing belt/water pump, break pads, plugs, etc - pretty much everything looked at/changed.

The good news is that the oils are perfect - both transfer case, diff and engine oils have been well looked after.

The issue we encountered though - the radiator was leaking. The guy who took it apart to change it and flush the coolant send us some pictures of the gunk that's gathered in there and it looks pretty bad:

https://imgur.com/a/M3Xs3

He is confident that he can replace the rubber hoses, replace the radiator, flush the coolant and it will be as good as new.

So far so good - one thing that worries me after cosulting another mechanic - what he said (and bare with me as I'm not that mechanically inclied) that if there was rust and the block is a steel block and if the engine has overheated - the cylinders might have expanded and might lead to excessive pressure inside the cooling system and overheating issues.

He claims that we can do the radiator swap and coolant flush and then try to load the engine up and see if it starts overheating or having radiator issues before investing more money into the water pump and timing belt replacement.

We have 2 months to actually return the car if it show any major mechanical issues so I'm starting to wonder what exactly we should do here.

Any advice would be very much appreciated.


PS I do realize I might just be overreacting and a standard flush + cooling system changes should be enough. Just not 100% sure if the engine might not be damaged in some way - the mechanic servicing it claims that the engine looks and works like new.

BlackCat81

Radiator leaks are very common on GX’s. If it’s got coolant in it, but just has some crusty goo forming in the corners of the radiator, it’s 99.9% going to be absolutely fine. My truck has 165k on it and it’s on it’s 3rd radiator.

Bastor

Thanks for responding BlackCat!

Yeah there was a lot of crust on the original radiator and a bunch of gunk, so I was pretty worried that it might cause a big engine issue but you're right - I'm just overthinking it.

chiph9

Normally, the radiator leaks around the edges, at the join from the metal fins to the plastic end caps. You'll see red "crystals" form along there.

This ... looks worse. Probably the wrong coolant was put in, or someone put windshield washer fluid in the overflow tank by mistake. Or ran plain water that then rusted.

Start by swapping the radiator and doing a cooling system flush to get whatever it is out of there. Replace the thermostat, and hoses for good measure. Let the water run a good long time so that the heater core in the dash gets cleaned out.

Refill with Toyota Long-Life coolant. Ask the mechanic to give you about a half-bottle to take home, as it will burp out air over the following couple of days and you'll want to top-off the overflow tank to the "min" line when the engine is cold.

Chip H.

Ali SC3

iTrader: (10)

I agree with Chip, flush the system or if at home stick a hose in it and get the rest of the bits out, insert new radiator, insert correct coolant and enjoy.
looks like they put the wrong coolant in or even something else. Also what the second mechanic said, would not happen.
The headgasket would blow or the head would warp way before anything happened to the block, and it would already be overheating all the time.

DiabloX22

I owned a shop for many years and never even heard of what that mechanic said! The guys that made the comments are absolutely correct. The head gaskets would blow if the engine over heated. there is a test that your mechanic can do easily to detect coolant in the air/fuel system. Just make sure when the flush is performed they flush the block also. If you do some research on here the best replacement radiators guys seem to go with are Koyo and Denso, also change the thermostat. You will be fine.

Bastor

Hey guys, thanks for all the responses.

You were 100% correct - the rust was quite bad but no signs of the engine overheating or any such issues - the radiator, water pump, hoses and thermostat were replaced, the coolant was flushed and everything is A+

Really appreciate all the replies.

artinist

make sure to replace the thermostat

Luap

Would it be silly to replace my radiator now , at 105K miles , as a preventative ??

JLee50

On my first GX, I preventatively replaced mine with the timing belt (a little late, around 109k). My current GX had the radiator replaced at 150k (timing belt is due at 210k) so I'll probably replace it at the 300k timing belt service, whether it needs it or not.

DiabloX22

It depends on the history also, has it been changed before or is it the factory radiator? I think if you are at 105k its time for the timing belt service, so do it all at once. If the radiator doesnt have signs of leakage, its fine. Look at where the plastic and metal meet, the seams, do they have a pinkish white corrosion? If so its time, if not, its fine.

chiph9

If you use it as a daily driver, you'll have plenty of warning (just check every week or two for the red crystals along the edges).

But if you're going on a cross-country trip and your miles are getting up there, you might want to think about it so that you're not stranded for a day along the way.

Chip H.

Bastor

Just a quick update - the car drives perfectly, only thing left is to have the wheels aligned.

bought it at over 160k miles so we serviced a lot of stuff (t-belt, CV boots and axels, filters, plugs, all oils, all air and oil filters etc)

Back on topic - the radiator was flushed, replaces with a new Denso Radiator, new cap, new thermostat, new water pump, new radiator hoses + full engine flush and fill it up with original Toyota coolant - after all of that I'm feeling pretty safe, the car has no issues (except for the need to get the axle aligned but that will happen with the wheel change in a few days)

Thanks for all the advice guys.


Are you losing any fluid? Any reason to worry about that? If there is a reason or it looks bad - go ahead. But these things might last. I'd check it for sure but I'm not sure it's worth to swap.

The reason mine was so badly rusted (I'm guessing) --> It was leaking from the top driver side, losing fluid, someone thought they can just top it up with water, which means the cooling fluid lost its anti-corrosive properties and rust went crazy.
In your case - I wouldn't worry unless you need to top up coolant.


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Not wanting to start another topic - I have a bit of a weird question.

Are the front driver and passenger side windows factory tinted or not?

I can't tell just by looking at them and I kind of wish to get rid of the foil - if there is any, since at night I sometimes have an issue seeing someone crossing on a crosswalk at night - visibility is kind of bad and I just don't like this type of tint.

But I really can't tell if there is foil or not - any way to check this? Sorry for hijacking my own topic