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Hi NitroForumz experts, my Nitro is a 2007 3.7l 42rle, bought it used with 183k km on it. I just notice my coolant from reservoir tank which is always on Max level are now almost on the minimum level, go to dealer and bought coolant they sold me the one that I share pic here. It's just confusing for me, do I need to mix this type of coolant with water? I was about to top up my reservoir tank, when I visit another auto mechanic shops to get some advice and got more confused, cause when the mechanic open the radiator cap, what seems to be inside is water, and when we check the coolant that dealer sold me, the color is red but my coolant reservoir have a greenish blueish color in it. I'm hoping to get some clarity here, it will be highly appreciated.🙏

 

[2ndgen]

Mopar sells this same coolant in two versions:
mopar 68048953AB - what you have in the photo, is 100% coolant, you need to mix/dilute it yourself
mopar 68163849AB - 50/50 premixed, it says in big bold letters "50/50 PREDILUTED - DO NOT ADD WATER"

If you don't know what's in the car, flush it first. Mixing coolants can be problematic. Who knows what the prior owners or quick-change oil jockeys put into it.

Get a bunch of distilled water (gallon jugs are like $1ea at walmart)--get 8-10 gallons, and find a few videos on how to flush it.

The basic idea is:

• you drain it with the petcock valve at the bottom of the radiator, then close the valve
• then take the top hose off the radiator and run it while filling it with just water until it flows out of the hose clear
• drain it from the petcock again
• put the top hose back on
• do your final fill w/coolant and water mixed 50/50 (or whatever ratio your climate needs)

There is a bleeder screw up top right before the top hose--remove that, then run it for a few minutes until it stops bubbling out the bleeder hole while checking the level/topping it off--then tighten that down and you should be good to go

Now, the bad news:
You probably have a leak.
Coolant levels generally should stay very stable--the fact that your coolant level decreased indicates you have a leak somewhere in your system.
Check:

• all your coolant hoses
• your radiator
• your heater core
• your exhaust for water
• your oil for water

The last two are worst case scenarios, but better to know than not.

 

[[email protected]]

Mopar sells this same coolant in two versions:
mopar 68048953AB - what you have in the photo, is 100% coolant, you need to mix/dilute it yourself
mopar 68163849AB - 50/50 premixed, it says in big bold letters "50/50 PREDILUTED - DO NOT ADD WATER"

If you don't know what's in the car, flush it first. Mixing coolants can be problematic. Who knows what the prior owners or quick-change oil jockeys put into it.

Get a bunch of distilled water (gallon jugs are like $1ea at walmart)--get 8-10 gallons, and find a few videos on how to flush it.

The basic idea is:

• you drain it with the petcock valve at the bottom of the radiator, then close the valve
• then take the top hose off the radiator and run it while filling it with just water until it flows out of the hose clear
• drain it from the petcock again
• put the top hose back on
• do your final fill w/coolant and water mixed 50/50 (or whatever ratio your climate needs)

There is a bleeder screw up top right before the top hose--remove that, then run it for a few minutes until it stops bubbling out the bleeder hole while checking the level/topping it off--then tighten that down and you should be good to go

Now, the bad news:
You probably have a leak.
Coolant levels generally should stay very stable--the fact that your coolant level decreased indicates you have a leak somewhere in your system.
Check:

• all your coolant hoses
• your radiator
• your heater core
• your exhaust for water
• your oil for water

The last two are worst case scenarios, but better to know than not.

Whooaa! This gives me clarity on a lot stuffs regarding radiator and coolant for my nitro. Thank you so much @2ndgen

 

[2ndgen]

Also, you can't tell anything by coolant color.
Different brands use different colors, even for the same (compatible) coolants.

Another option (what I use) is Zerex G05

 

[2ndgen]

I forgot to mention, you also should check your water pump for leaks.
If there's a drip (or more) of coolant out the bottom of your car (wait till everything is dry, and park over dry pavement and wait and see), that would be because your water pump gasket is leaking and it's coming out the internal weep hole.

That one is harder to tell because in that area you could get leaks of oil, ATF from the power steering pump, or coolant from the water pump weep hole--none of which are good, but a coolant leak there is the easiest of the three problems to fix (just replace the water pump).

If you identify a leak, usually you need to drain the system to repair it--but as long as you use a clean bucket you can reuse the fluid you empty out of it once your repair is done--no need to waste money on fresh coolant again.

 

[Nitrogen]

if you think you have a leak, just top up the reservoir with water and find/fix the leak, then flush and change all the coolant fluid,

 

[2ndgen]

You can also put some dry cardboard under your engine when you park to catch any drips--a good option if you're parking outside and the pavement is always wet.

 

[2010NitroHeat]

Nitros use HOAT type coolant. The yellowish green stuff they sell in the stores these days tends to be a "universal" type coolant that they claim is good for all vehicles, and can mix with all coolants. I don't know if that's true or not though. The Mopar HOAT coolant is either orange or reddish. They changed the color at some point. When I buy HOAT coolant, I just buy concentrated Zerex G05, which is light gold color, and mix it with distilled water.

 

[2ndgen]

Also, not all brands of HOAT are the same. I prefer mine without 2-EHA. Both the Mopar and Zerex G-05 are without 2-EHA. Several other brands of HOAT do have 2-EHA.

 

[[email protected]]

if you think you have a leak, just top up the reservoir with water and find/fix the leak, then flush and change all the coolant fluid,

@Nitrogen this is what I am planning to try. Still I am observing the coolant level, is it still a possible leak even if the coolant level stays just above the minimum mark of the reservoir? I was just observing it, although it lost a fair amount of coolant from Max mark of the reservoir, the coolant stays on minimum level, it's a been a week now. if the coolant goes beyond minimum, I will add distilled water and observe if the level will go down again. Then I will do a flush this week. Thank you @Nitrogen

 

[[email protected]]

Nitros use HOAT type coolant. The yellowish green stuff they sell in the stores these days tends to be a "universal" type coolant that they claim is good for all vehicles, and can mix with all coolants. I don't know if that's true or not though. The Mopar HOAT coolant is either orange or reddish. They changed the color at some point. When I buy HOAT coolant, I just buy concentrated Zerex G05, which is light gold color, and mix it with distilled water.

@2010NitroHeat I've read that this brand is the best, and I will try to look for it, I'm working and living here in the middle east, it can be tricky to find some stuffs here. Even the dealer here at most times don't have parts, specially for older models. Maybe someone here can answer if that "universal" type coolant is really good, I think there will be a lot of people that will be curious to know truth. Thank you!

 

[[email protected]]

I forgot to mention, you also should check your water pump for leaks.
If there's a drip (or more) of coolant out the bottom of your car (wait till everything is dry, and park over dry pavement and wait and see), that would be because your water pump gasket is leaking and it's coming out the internal weep hole.

That one is harder to tell because in that area you could get leaks of oil, ATF from the power steering pump, or coolant from the water pump weep hole--none of which are good, but a coolant leak there is the easiest of the three problems to fix (just replace the water pump).

If you identify a leak, usually you need to drain the system to repair it--but as long as you use a clean bucket you can reuse the fluid you empty out of it once your repair is done--no need to waste money on fresh coolant again.

I will visit an automotive shop this week and I will point this out to the mechanic just in case they missed knowing about this. You all guys are really helpful! I will update you all, hoping someone can refer back to this post and help them in case they face the same issue. Thank you @2ndgen

 

[Nitrogen]

if the coolant level keeps falling, you have a leak, 'Find/Fix It Now ' it will only get worse and then you will damage the engine, the most common cause of this is the water pump leaking But you do not always see the leak because the coolant leak evaperates with the hot engine, then as the engine cools down the pressure in the cooling system drops and the leak stops (no pressure forcing coolant out), so you never see the leak when the engine is cold but as each day passes the leak gets worse untill something bad happens, so fix it as soon as possible,
BUT it could be something else, the water pump is the common starting point, unless you had overheating issues then that could be very different

 

[[email protected]]

Just an update. I bought a green coolant and decided to top up my reservoir a week ago, so for me to see if the there will be a lost of coolant, using my nitro only 3x a week, and checking all fluids and oil before my drive, I am relieved to see the coolant level is stable. Some told that it's normal for coolant to go low especially if it's hasn't been change for a long time. Still I am thankful for all the tips, I heard from you guys. Now I definitely know where to look for just in case I encounter the same issue.🙏

 

[2ndgen]

I wouldn't risk mixing unknown coolants together.
When coolants aren't compatible they can turn to sludge quickly and block coolant passages--and on these 3.7L motors that's a death sentence.
I'd highly recommend you flush it and put all new coolant in so you know exactly what's in the system.

 

[[email protected]]

I wouldn't risk mixing unknown coolants together.
When coolants aren't compatible they can turn to sludge quickly and block coolant passages--and on these 3.7L motors that's a death sentence.
I'd highly recommend you flush it and put all new coolant in so you know exactly what's in the system.

Thank you for reminding me @2ndgen, I will.🙂