Over the past 5 months I've had 6 or so big drops of coolant from the area of the overflow. That is based on location of the drops. Once in December and then today.
What would cause this and should I be concerned? No overheating.

Just picked it back up after service yesterday. They are indicating that it was related to a leak in the AC system. Ironically I had it serviced a week or so ago and they "fixed" one O ring leak and recharged it that day. It was the next day that I noticed the fluid on the ground. This time they "fixed" another O ring.
Kind of makes sense as the snot green color is from the black light dye in the AC fluid and where it dripped was back near the firewall of the vehicle. (that was part of what was a mystery to me). I and the tech couldn't even find the radiator overflow. Not sure if its not opaque like most or just really well hidden.
Hopefully they finally have everything fixed!

This message has been edited. Last edited by: Powers77,

Is there transmission fluid getting in your coolant? I remember some Nissans having an issue of coolant contaminating the ATF or ATF in the coolant.

Looks like it was coolant getting in the ATF:

http://www.nissanproblems.com/...estroy-transmission/

Don't think so. Pretty much snot rocket green. ATF is still only red, right?

Recall hearing the same but this is a 2018. Pretty sure that was earlier version.

If it’s a 2018 and under warranty I’d take it in and have the dealership check it out. And get a receipt to prove you did so, in case a problem develops down the road.

Combustion pressure getting access to the coolant via head gaskets, crack, piston rings, etc.

quote:

Originally posted by arfmel:
Is there transmission fluid getting in your coolant? I remember some Nissans having an issue of coolant contaminating the ATF or ATF in the coolant.

Not to be a poopy-pants, but that's been a while back, and the OP mentioned his vehicle is a 2018. Looking a bit further at the article, it appears the vehicles affected (Frontier, Xterra, Pathfinder) were models equipped with the 4.0-liter V6 engine; Armada uses the 5.6-liter V8.

I'm totally with you on the suggestion to have it dealer-checked.

Yeah I'll be getting it in early this week as I'm only 100 miles from going out of warranty.
More curious than concerned really. Think it's just pushing "extra" out. Just don't understand why it's so irregular. Neither time was it really hot or anything like that.

quote:

Originally posted by Excam_Man:
Combustion pressure getting access to the coolant via head gaskets, crack, piston rings, etc.

Agreed. I had a car do that years ago and it was caused by blown head gasket.

There is a pressure cap either on the radiator or the reservoir. It might be bad.

quote:

Originally posted by grumpy1:

quote:

Originally posted by Excam_Man:
Combustion pressure getting access to the coolant via head gaskets, crack, piston rings, etc.

Agreed. I had a car do that years ago and it was caused by blown head gasket.

I'm thinking head gasket, too, BTDT. I'd have that checked out very carefully.

quote:

Not to be a poopy-pants, but that's been a while back, and the OP mentioned his vehicle is a 2018

OP didn’t mention the year model until after my initial post about the possible issue of ATF/coolant intermixing, Mr Poopy Pants

Is the coolant level in the radiator and the coolant overflow tank normal. A bad radiator cap can cause issues here if it won't proper PSI rating all the time.

Check your radiator cap. If it's bad, the coolant can boil at normal operating temperatures and it will blow coolant out of the overflow.

quote:

Originally posted by Powers77:
Yeah I'll be getting it in early this week as I'm only 100 miles from going out of warranty.
More curious than concerned really. Think it's just pushing "extra" out. Just don't understand why it's so irregular. Neither time was it really hot or anything like that.

My 18 Titan xd has a 5 year / 100k warranty. Your truck should too. Same engine and all.

quote:

Combustion pressure getting access to the coolant via head gaskets, crack, piston rings, etc.

I'd be worried about this. Go see the dealer.

You may have a cracked block or blown head gasket. Check your oil, does it look like frothy chocolate milk?

Definitely check your engine pressure and such to see if it is a broken Head Gasket/rings/piston/ issue.

As it is probably under warranty, I'd run it by the Stealership.

Don't forget to have the temp. sensor/thermostat/thingy checked as it could be wonky and causing overheating.

H&K-Guy

quote:

Originally posted by walker77:

quote:

Originally posted by Powers77:
Yeah I'll be getting it in early this week as I'm only 100 miles from going out of warranty.
More curious than concerned really. Think it's just pushing "extra" out. Just don't understand why it's so irregular. Neither time was it really hot or anything like that.

My 18 Titan xd has a 5 year / 100k warranty. Your truck should too. Same engine and all.

Interesting, Basic warranty is listed at 3 years and 36,000 miles. Powertrain 6 years 60,000 miles. Odd that they appear to be different.
Taking it in tomorrow morning.
Looking at where it dripped I can't figure out where the heck it's coming from. Almost directly under passenger side foot area.

Based off of the area you mention- passenger side- maybe the heater core or hoses to it?

quote:

Originally posted by Bulldog:
Based off of the area you mention- passenger side- maybe the heater core or hoses to it?

That would be my guess also and if it's the heater core, better get it in before the warranty is up.