Which Coolant?
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
Which Coolant?
The other (very cold) day I got a warning for coolant level. I checked the level, and it is a bit low, so I was going to add a little to get through the rest of the winter, then change it in the spring.
I don't know whether the coolant has ever been changed in the past; the car had 70k miles on it when I got it. I pulled a sample from the reservoir, expecting either pink/purple (G40) or blue (G48), but it was a pale yellowish green. Not neon green like the old stuff, more like light blue mixed with yellow, or maybe blue yellowed with age?
So, I could add some distilled water and worry about it later, or I could get some G40 or G48 and use that. As far as I can tell, G48 is what was in it originally, but G40 is allowed (recommended?) for drain and flush. I'll probably go with G40 in the spring. as that is what is in our other Benz.
Checked the Zerex (Valvoline) web site and they recommend G40 for both cars.
I've also heard that G05 and G48 are compatible. I have G05 on hand and could add a little of that, too. Or I could soldier on the way it is as there aren't going to be many more really cold days this year.
What do you think?
I don't know whether the coolant has ever been changed in the past; the car had 70k miles on it when I got it. I pulled a sample from the reservoir, expecting either pink/purple (G40) or blue (G48), but it was a pale yellowish green. Not neon green like the old stuff, more like light blue mixed with yellow, or maybe blue yellowed with age?
So, I could add some distilled water and worry about it later, or I could get some G40 or G48 and use that. As far as I can tell, G48 is what was in it originally, but G40 is allowed (recommended?) for drain and flush. I'll probably go with G40 in the spring. as that is what is in our other Benz.
Checked the Zerex (Valvoline) web site and they recommend G40 for both cars.
I've also heard that G05 and G48 are compatible. I have G05 on hand and could add a little of that, too. Or I could soldier on the way it is as there aren't going to be many more really cold days this year.
What do you think?
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From: South Texas
2014 GLK350 base model (active) ; 2001 E320 base (retired); 2001 Wrangler soft-top
A year or so ago (two? memory is the first thing to go in older ages), I replaced the radiator in the wife's 2001 E320 ... I used Zerex G05 (yellow), which is Zerex's call for the OEM requirement.
Yea, it's an older model than our GLKs, but your post got me curious, as I need to flush the wife's 2014 GLK350 soon. Page 340 in the Owner's Manual states, "the following product is strongly recommended for use in your vehicle: MB 325.0 anti-corrosion antifreeze agent".
Which when I do a search for "2014 MB 325.0 coolant", I get hits from various sites for "blue".
I also stopped at a MB dealership website, which has an extensive description about coolant ... it mentioned, "different types of coolants can be the same color, so don't choose based on color alone". It never mentioned exactly what should be used, but to consult your manual.
Gotta go out to the barn in a bit, so I'll swipe a syringe from the horse's tack trunk and check the color of our GLK.
Yea, it's an older model than our GLKs, but your post got me curious, as I need to flush the wife's 2014 GLK350 soon. Page 340 in the Owner's Manual states, "the following product is strongly recommended for use in your vehicle: MB 325.0 anti-corrosion antifreeze agent".
Which when I do a search for "2014 MB 325.0 coolant", I get hits from various sites for "blue".
I also stopped at a MB dealership website, which has an extensive description about coolant ... it mentioned, "different types of coolants can be the same color, so don't choose based on color alone". It never mentioned exactly what should be used, but to consult your manual.
Gotta go out to the barn in a bit, so I'll swipe a syringe from the horse's tack trunk and check the color of our GLK.
Last edited by calder-cay; Mar 2, 2023 at 01:57 PM.
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2013 glk 350
I would put in water then flush it out and use the proper stuff when you can. Since it’s probably not original judging by color, get a 3$ tester to be sure you’re near 50/50. Corrosion protection is something you get with a 50/50 mix and that is needed.
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From: South Texas
2014 GLK350 base model (active) ; 2001 E320 base (retired); 2001 Wrangler soft-top
This is a follow-up to my previous post.
I syringed out some coolant from the reservoir and it's yellow.
I syringed out some coolant from the reservoir and it's yellow.
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From: South Texas
2014 GLK350 base model (active) ; 2001 E320 base (retired); 2001 Wrangler soft-top
Yes, but this is "educational", for better understanding about choice:
https://blog.fcpeuro.com/how-to-pick...t-for-your-car
For example: the Zerex GO5 I used in the older MB, is yellow. G48 is blue. Remember, color should not be the main consideration. From the link above:
-----------
G05 (yellow) and G48 (blue) should be compatible with each other.
... and further on:
Glysantin G05 (HOAT, Silicates)* pH-value 6.5
Chrysler MS-9769
Mercedes-Benz DBL 7700.20 Page 325.0
John Deere JDM H 24
Leyland BLS.22.AF.01
Ford North America WSS-M97B51-A1
(G05 can be mixed with G48 coolant regardless of color. It is advisable to switch to G48 due to current availability after performing a full cooling system drain, flush, and re-fill)
So, for my 2014 GLK350 Base, my best guess is I'll use Zerex G05 to top it up ... I may switch to G48 when doing a flush... of course, I'll investigate a bit more.
https://blog.fcpeuro.com/how-to-pick...t-for-your-car
For example: the Zerex GO5 I used in the older MB, is yellow. G48 is blue. Remember, color should not be the main consideration. From the link above:
-----------
Below we list the different coolant compatibility and what we offer to service your car:
G30, G33, G34, G40, G44 should all be compatible with each other.G05 (yellow) and G48 (blue) should be compatible with each other.
... and further on:
Glysantin G05 (HOAT, Silicates)* pH-value 6.5
Chrysler MS-9769
Mercedes-Benz DBL 7700.20 Page 325.0
John Deere JDM H 24
Leyland BLS.22.AF.01
Ford North America WSS-M97B51-A1
(G05 can be mixed with G48 coolant regardless of color. It is advisable to switch to G48 due to current availability after performing a full cooling system drain, flush, and re-fill)
So, for my 2014 GLK350 Base, my best guess is I'll use Zerex G05 to top it up ... I may switch to G48 when doing a flush... of course, I'll investigate a bit more.
Last edited by calder-cay; Mar 2, 2023 at 04:26 PM.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
The available information is very confusing, as far as I'm concerned.
(Hope I get this right!) The two concentrate candidates for the GLK are 325.0 and 325.6 which translate to G48 (blue) and G40 (pink) respectively. The cutoff is April 2014. (Mine is pre-cutoff, so should be 325.0/G48/blue.)
To further confuse things, 326.0 and 326.6 Are the same things except premixed.
So it's the number after the decimal point that differentiates the coolants.
Since mine should have G48 (blue), and G05 is yellow, and blue + yellow makes green (which is probably what I have), I think I'll just add some (more) G05 for now. I have pre-mixed G05 on the shelf. G40 is the newest spec, and suitable for all years, and what is spec'd for the GLS, so I'll flush the system and switch to that in the spring.
Unless someone has a good reason not to!
(Hope I get this right!) The two concentrate candidates for the GLK are 325.0 and 325.6 which translate to G48 (blue) and G40 (pink) respectively. The cutoff is April 2014. (Mine is pre-cutoff, so should be 325.0/G48/blue.)
To further confuse things, 326.0 and 326.6 Are the same things except premixed.
So it's the number after the decimal point that differentiates the coolants.
G05 can be mixed with G48 coolant regardless of color.
Unless someone has a good reason not to!
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
You have it right. If your build is prior to April 2014, then you need spec 325.0 Mercedes BQ 1 03 0004 which is the blue coolant. And yes, the blue and the yellow coolant are supposed to be compatible.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
Yeah, the only fly in the ointment is that you can flush the system and refill it with 325.6 and the color of mine doesn't match either! Still, I'm guessing adding a pint or so of G05 50/50 mix isn't going to ruin anything.
