Recently bought a 99 V6 4x4 automatic. Checked the radiator today (should've done this before I bought it :bash: ) and noticed that the coolant is a sludgy grey color. The overflow has it too and is a bit gooey. The engine oil looks perfect, haven't had it long enough to tell if it's losing oil somewhere. The auto tranny fluid looks nice and red. I drained the coolant and most of it is green/yellow. I'm thinking it's oil from somewhere cause it doesn't want to mix and the grey ends up on the top. I added in some Prestone radiator cleaner/water and it says to run for a few days(3-6 hours at least). I opened the cap and all I see is grey. Hopefully it's just the cleaner doing the work and needs to be drained. Someone said it could be stop leak. I read somewhere else it could be related to the tranny for cooling or from a tranny cooler. It has 2 radiators could the front one be a tranny cooler? Anyone have any ideas on this one? The truck seems to run strong. After I put the cleaner in I drove it around for about an hour, got up to 80-90 a few times, had the heat running full blast. It shows no signs of overheating. One other thing, I put in the Prestone cleaner which was like 2 quarts and then I added 1 gallon of water plus maybe a few more ounces. It was full, I thought it would hold more. Thanks for any assistance...
GREY coolant?????
- Thread starter surfh2o
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blk runner00
New member
just a thought but it could be something like barsleak or a pour in sealer that was tring to cover up leak. not to sure about the a/t fluid although a know problem on these 3rd gens. try running cleaner a couple times and keep an eye on it. plus tranny cooler is the two lines going in/out of rad. on bottom.
I flushed the radiator a week ago and the coolant looks like it sits on the bottom and oil on the top. Didn't seem like much. I ran radiator cleaner in it for a week and flushed it on Saturday. Still looks about the same. I'm thinking it has to be engine oil. I changed the oil and it looks perfect. I'm just not sure what to do at this point. I heard that the crank case builds more pressure than the radiator and that's why it's only a one way leak. So i'm thinking it should be a small leak right? Should I get a true diag or should I buy something that claims to seal the leak? Do I just need a new head gasket??? Would it be worth it to do it now or wait? If I wait and it blows couldn't that potentially cause more damage?? Please help I'm desparate.
Jay
Jay
Qyota
New member
If you have oil in your coolant, chances are the head gasket is already "blown". Oil in the coolant is the "better" of the two problems (versus coolant in the oil), but it's still not good.
There might be other ways oil can enter the coolant, but I'm not familiar enough yet with the T4R to know where those points might be. Water pump is a guess.
FWIW- my coolant is bright pink!
There might be other ways oil can enter the coolant, but I'm not familiar enough yet with the T4R to know where those points might be. Water pump is a guess.
FWIW- my coolant is bright pink!
Jordan Petry
New member
Have it fixed right, definitely do NOT put in bars leak or stop leak...they are meant to seal small holes in your engine, not only the ones that are the cause of your leak, but coolant passages and other things...think about it, do you really want to put that crap in your engine? IMO it's not worth it to do a half ass job the first time. Jm .02c, good luck
Yeah I just bought it though and it's my fault I didn't check it out better. I already spent more than I was planning. Anyone have any ideas of the costs? I guess it's better I do it now then have it blow bad later causing more damage. Guess it's hard to price the fix when I really don't even know what's wrong yet. Should I mention it at all to the seller, or is it my fault?
Jordan Petry
New member
Did you purchase it from an individual or a dealer? I know in some states there is an implied 30 day warranty on vehicles sold from an individual and if it's a dealer you might be able to squeeze some money out of them. Good luck and I hope it works out for you. I've been driving my t4r w/ a head gasket leak for about 6k miles now w/ no problems...I just add a little coolant every now and again but the coolant has stayed clear and my oil is not milky. Best of luck to ya, Jordan
scotts97T4Rltd
New member
If i were a betting man, id say that its not oil, its transmission fluid.surfh2o said:
Just replace the radiator, it sounds like you have transmission fluid mixing with your coolant. (which is a common problem) your radiator is busted.
The radiator actually looks new. I'm pretty sure it isn't factory at least. I guess red and green could still make the color I'm seeing. I wonder if it would be a darker color if it was engine oil. I just did a change and the oil was dirty. So maybe that would make the color darker and since the color hasn't changed since the oil change maybe it is the radiator, possible as well since it does look like some generic one and could be crap or a crap install...hmmmmmmmm. There isn't anyway to tell for sure is there?? Thanks
DavidAlexander
New member
If it is grey blobs not mixing with the coolant, sounds like engine oil in the coolant. Hopefully it is just the head gasket, not an overheated car with a warped head. I wouldnt go just by how the oil looks, send it to blackstone to see if it has other fluids in it.
The problem could have already been fixed too. It can take many flushes to remove the oil that is in the cooling system if that is what happened. If just a small amount appears after each flush it could be residual in the cooling system.
One thing to think about though, if it is oil in the coolant, the hoses that run to the radiator can be impregnated and compromised by the oil. They loose their strength and will eventually fail.
The new radiator and the small amount of globs in your coolant makes me think it was fixed before you got it. Just not flushed enough to remove all the residual oil.
Like Scott said, their are many stories of the transmission cooler that runs through the radiator failing also. Those seemed to sludge up the coolant though (strawberry milkshake), not separate into to layers.
The problem could have already been fixed too. It can take many flushes to remove the oil that is in the cooling system if that is what happened. If just a small amount appears after each flush it could be residual in the cooling system.
One thing to think about though, if it is oil in the coolant, the hoses that run to the radiator can be impregnated and compromised by the oil. They loose their strength and will eventually fail.
The new radiator and the small amount of globs in your coolant makes me think it was fixed before you got it. Just not flushed enough to remove all the residual oil.
Like Scott said, their are many stories of the transmission cooler that runs through the radiator failing also. Those seemed to sludge up the coolant though (strawberry milkshake), not separate into to layers.
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This is probably from mixing Toyota red coolant with the green coolant. These motors can use their but they should not be mixed, this creates sludge. I would do a very good flush including cleaning the overflow tank. It may take a couple rounds to get it all out. Then choose what color coolant you want to go with.
Many owners and shops mix these without ever knowing.
Many owners and shops mix these without ever knowing.
Well I was driving into work this morning so I could take it to the shop. I overheated quick and had no heat. Not sure why all of the sudden the t-stat is stuck/bad. Maybe the flush got something in the valve. Is there a way to check the t-stat to see if it's broke or just stuck? At that point should I just replace it?
I topped the coolant off and started it up, added a little more coolant. Blasted the heat and it came to temp and held this time. Maybe it burped itself somehow. I still might do an incline "burp", but it seems fine now. I took it to the Toyota shop and told him about the oil in the radiator. He said first of all it is very rare for the 3.4's to gave head gasket failure. He said if there was a head leak then there should be water in the oil. He said a gasket leak is not just a one way leak and would show in the oil. When I pointed out the after market radiator. He said well they replaced it for a reason and was probably associated with the tranny. He thinks it is just residue left over from that and it's hard to get out cause it doesn't mix well. He said it could be a leak occurring at the water pump. All he said was watch the oil. It was cool they didn't try to rob me but I wish they could've done some kind of diagnostic. This could make sense cause when I changed the oil the level was good and the oil was nice and dirty.
DavidAlexander
New member
surfh2o said:
Glad to here it is working fine. How long ago did you buy this? If they replaced the radiator due to the transmission cooler leaking it is almost positive that coolant came in contact with the internals of the transmission. There have been some that have tried the flush method but you really need the tranny rebuilt if ANY coolant reached it. That is why I suspect the previous owner got rid of the car with a cheap $150 radiator fix and radiator/tranny flush.
I would go back to where you got it and demand to know why they replaced the radiator and let them know that your Toyota mechanic suspected it was from the tranny cooler. If they just replaced the radiator, flushed, and sold it to you they did not act in good faith. If they previous owner did this "easy fix" and traded it in, you may be out of luck.
Either way, the place/person from whom you bought it owes you some answers.
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The tranny fluid looks great. See and I have this issue when I'm coming to a stop it feels like it grabs and shutters to the left, a little loud too. The guy I bought it from said that this was the only issue he knew about. Says it's somthing with the front brake sticking. Also, claims his mechanic took a look at it, but we all know that may not be saying much. I'm hoping it isn't something with the tranny somehow. Sometimes when I bring it from Park to Drive I let the brake go and the vehicle doesn't move. I hit the gas and it feels like it breaks free. I put it in neutral when stopping and had the same effect. Neither happens every time. I'm also in the process of ripping out the rear bumper. That sucker it rusted the F out. The more I try DIY the more I find out that I break a lot of bolts. I want my Taco back. :bash: I'm gonna get this baby straight though hopefully.
blk runner00
New member
jordan,
i wasnt saying to put barsleak in i said that could have been part of the problem. i also wouldnt use this product as is doesnt really really do the engine any good.
surf hope it all works out and maybe try to take it by to a tranny shop and let them drive it, and check the fluid.
i wasnt saying to put barsleak in i said that could have been part of the problem. i also wouldnt use this product as is doesnt really really do the engine any good.
surf hope it all works out and maybe try to take it by to a tranny shop and let them drive it, and check the fluid.