Coolant overflow tank question

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Jan 3, 2021
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Hello. I bought a used 08 Toyota Highlander Limited yesterday with the V6. Drove it for quite a while and noticed when I got home that there was coolant on the ground. I lifted the hood and the overflow tank is completely full and dripping on the ground. I checked the oil again and checked the coolant level this morning and they both are full, look good with no apparent oil/coolant mixture. I noticed Thursday when I test drove it that it and checked under the hood, that the tank was full but I’m new to highlanders so I wasnt sure if that was an issue or not.
what I THINK happened is their mechanics just topped it off and I need to remove some fluid from the overflow tank. Ive got approx. 100 miles on it already and it drives great, no mechanical issues, no overheating, etc.

is there anything else I can check and does my thinking seem correct or do I need to have a chat with the dealer?
thanks in advance for your assistance.
 
I would have checked for leaks BEFORE selling it. Most dealers just unload a car from the transporter, detail it, then put it out on the lot.
Exactly my point.

And still, sometimes things get missed, and sometimes **** just happens.

In any case, a new coolant tank is a drop in the bucket to a volume dealer, and worth the cost to keep a happy customer.
 
I'm assuming it was dripping because it was full and when warmed up it pushed coolant out the tank vent. If it is a cracked coolant tank, then the dealer should replace that for you.

If the tank isn't cracked, I'd bet they just topped it off. When I buy a used car, I drain and fill the coolant system asap just to make sure it is fresh and that the right stuff is in there. But I wouldn't worry about it. Just check it before and after each drive a few times. Once it pushes out the excess it should settle into a normal level. I'd test it with the little Prestone tester, too. Then swap it out when time/weather permits.

My cousin just a 2018 Jeep JK Wrangler and brought it over so we could go through it. Everything was perfect except one thing. The coolant in the bottle was very low, as in barely any in there. I happened to have the proper Chrysler coolant and started to fill it when it began dripping all over the floor underneath. It was a cracked bottle and appears to have been that way from the factory. It had 30k on it. Fortunately, there still was enough that it appeared to have caused no problem. I ordered a new tank for him for 30 bucks at Advance Auto, picked it up and then installed it and topped it to the proper level. He took the receipt to the dealer and they reimbursed him. All is good now. But we went over EVERYTHING. It was probably 3 days after he brought it home. He had a 90 day warranty from them which also got him a new windshield. He found a small crack in it, so they replaced it, too.
 
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I would think you would have noticed on your inspection if the coolant was overfilled. You did check fluids before buying?
 
It can't hurt to have a conversation with the seller just in case it reoccurs. Most likely it was just overfilled and should be okay since whatever amount was extra has already spilled over.
I’ll continue to drive it as it seems to be operating fine, I just wanted to make sure it didn’t indicate something more. I have over 70 receipts/maintenance records all from the Toyota dealer (not the one I bought it from) that shows they did everything Toyota told them to do maintenance wise. Since it’s not leaking from anywhere aside from the overfill hose, all the fluids appear to be correct in level and appearance, aside from the overflow tank in question, I suspect their shoo guys just overfilled it. I’ll keep an eye on it and see how it does. Thank you.
 
I would think you would have noticed on your inspection if the coolant was overfilled. You did check fluids before buying?
Of course I did. Apparently I’m not perfect and something slipped thru, which is why I posted here. Please accept my apology for letting you down.
 
I'm assuming it was dripping because it was full and when warmed up it pushed coolant out the tank vent. If it is a cracked coolant tank, then the dealer should replace that for you.

If the tank isn't cracked, I'd bet they just topped it off. When I buy a used car, I drain and fill the coolant system asap just to make sure it is fresh and that the right stuff is in there. But I wouldn't worry about it. Just check it before and after each drive a few times. Once it pushes out the excess it should settle into a normal level. I'd test it with the little Prestone tester, too. Then swap it out when time/weather permits.

My cousin just a 2018 Jeep JK Wrangler and brought it over so we could go through it. Everything was perfect except one thing. The coolant in the bottle was very low, as in barely any in there. I happened to have the proper Chrysler coolant and started to fill it when it began dripping all over the floor underneath. It was a cracked bottle and appears to have been that way from the factory. It had 30k on it. Fortunately, there still was enough that it appeared to have caused no problem. I ordered a new tank for him for 30 bucks at Advance Auto, picked it up and then installed it and topped it to the proper level. He took the receipt to the dealer and they reimbursed him. All is good now. But we went over EVERYTHING. It was probably 3 days after he brought it home. He had a 90 day warranty from them which also got him a new windshield. He found a small crack in it, so they replaced it, too.
I always change out fluids when I buy a used car. This one shows the Toyota dealer changed ALL of them along with plugs, etc at the 100,000 mile service so I’m gonna wait on that.
 
Exactly my point.

And still, sometimes things get missed, and sometimes **** just happens.

In any case, a new coolant tank is a drop in the bucket to a volume dealer, and worth the cost to keep a happy customer.
It was a local trade from an older couple. I actually found out I know their neighbors and they bought it new, always garaged and took it to the dealer for every service. It looks mint.
would you suggest I drain out some of the overflow fluid or just leave it? I have an old turkey baster in the garage I can use to remove some.
 
I always change out fluids when I buy a used car. This one shows the Toyota dealer changed ALL of them along with plugs, etc at the 100,000 mile service so I’m gonna wait on that.

Then unless I misunderstood something, I wouldn't worry about it. Just check it before and after each drive until it looks like it has settled down and the coolant is at or above the proper marks in the coolant tank. It sounds as if they just overfilled it. No biggie, if that's the case. And being dealer serviced, it should have the proper Toyota coolant. I'd double check at least the color on that, but I'd be surprised if a Toyota dealer put anything else in it.

Sounds like you got a good one!
 
Then unless I misunderstood something, I wouldn't worry about it. Just check it before and after each drive until it looks like it has settled down and the coolant is at or above the proper marks in the coolant tank. It sounds as if they just overfilled it. No biggie, if that's the case. And being dealer serviced, it should have the proper Toyota coolant. I'd double check at least the color on that, but I'd be surprised if a Toyota dealer put anything else in it.

Sounds like you got a good one!
It’s Pink which i believe is what Toyota uses now versus the old red?
I hope I did get a good one. When I buy a used car with this many maintenance records, I get down right giddy. Lol. Thanks for your reply.
 
"I have an old turkey baster in the garage I can use to remove some."

Were it my vehicle I'd take my baster out in the morning when everything is cold and reduce the coolant level to the COLD or MIN mark.
Any level you can easily spot is a good place to start.

I hope you did get a good one. Sounds like your dealer is an OK sort.
 
"I have an old turkey baster in the garage I can use to remove some."

Were it my vehicle I'd take my baster out in the morning when everything is cold and reduce the coolant level to the COLD or MIN mark.
Any level you can easily spot is a good place to start.

I hope you did get a good one. Sounds like your dealer is an OK sort.
Thank you for the advice. I plan to do just that. Have a good day.
 
I think you said you have a 30 day warranty? I didn’t catch how many miles were on the Highlander, but no matter...it probably was overfilled (it’s easy to do that on an overflow tank) and then it just simply comes out. Keep an eye on it, drive it a bunch in the next week and if there is no problem? I wouldn’t worry about it. You could call the dealer you bought it from just to document...maybe you should actually, but I’d also tell them that you’ll just be keeping an eye on it and will call back if it happens again.

Know what’s funny? I checked my coolant overflow tank on my 2016 Avalon last night, it was maybe an inch low...so I filled it up and I ended up going over the fill mark. Wonder if it spilt out? I put a good 20 miles on it last night, I’ll have to check.

Edit — Checked it, now it’s back to being an inch underfilled again...remind me to not look under my hood anymore.
 
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Of course I did. Apparently I’m not perfect and something slipped thru, which is why I posted here. Please accept my apology for letting you down.
Then it wasn't likely overfilled, drain the excess and see what happens. Not a big deal unless a headgasket issue forced the coolant out.
 
I think you said you have a 30 day warranty? I didn’t catch how many miles were on the Highlander, but no matter...it probably was overfilled (it’s easy to do that on an overflow tank) and then it just simply comes out. Keep an eye on it, drive it a bunch in the next week and if there is no problem? I wouldn’t worry about it. You could call the dealer you bought it from just to document...maybe you should actually, but I’d also tell them that you’ll just be keeping an eye on it and will call back if it happens again.

Know what’s funny? I checked my coolant overflow tank on my 2016 Avalon last night, it was maybe an inch low...so I filled it up and I ended up going over the fill mark. Wonder if it spilt out? I put a good 20 miles on it last night, I’ll have to check.

Edit — Checked it, now it’s back to being an inch underfilled again...remind me to not look under my hood anymore.
I drained it out to the max fill mark, the. Drove it about 125 miles today, no issues and it’s about where I left it level wise so I think it was just overfilled. Thanks for those ofmyou that helped.
 
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