Can I mix Zerex G-05 and Mopar MS9769 coolant?

[hardtailpan]

I have a gallon of each and was planning on doing a system flush and changing my hoses over labor day. I can't see any reason why it wouldn't be ok to mix em', but I'm questioning that reasoning. Anybody do this? Anybody see a reason not to, other than it will create a weird color?

 

[Ante_Up]

I think as a general rule... No. If it's the same type of coolant besides the color, like both are ethylene glycol... It's fine. If it's two different chemical make ups, it can actually form a gel that could cause overheating issues, etc

 

[Ante_Up]

That being said... From a quick Google search it appears that they are compatible, but antifreeze is relatively inexpensive... I'd likely opt for a full flush and fill with the same type

 

[pagrey]

I'd use all g-05, it isn't too expensive.

 

[hardtailpan]

Yeah, you're both right, there is no reason not to use all of one or the other as the cost is negligible. No reason to take a chance.
Thanks for pointing out what should've been obvious to me lol!

 

[Aviatortroy]

I just did a drain and flush last week when I did my water pump. Make sure you pull the block drain too. I pulled my heater hoses off and flushed them too. Some people get uptight about not using distilled water, but if you pull the block drain, open the radiator petcock, and the heater hoses, and let ‘er rip with a garden hose, it WILL all drain back out. Then I hooked up everything, and refilled with the Zerex GL05 mixed 50-50 with distilled water. That’s where having distilled actually counts.

And one of these type of funnel kits makes things way easier as well.
https://www.amazon.com/dp/B01A2CQSU6/?tag=wranglerorg-20

 

[hardtailpan]

I just did a drain and flush last week when I did my water pump. Make sure you pull the block drain too. I pulled my heater hoses off and flushed them too. Some people get uptight about not using distilled water, but if you pull the block drain, open the radiator petcock, and the heater hoses, and let ‘er rip with a garden hose, it WILL all drain back out. Then I hooked up everything, and refilled with the Zerex GL05 mixed 50-50 with distilled water. That’s where having distilled actually counts.

And one of these type of funnel kits makes things way easier as well.
https://www.amazon.com/dp/B01A2CQSU6/?tag=wranglerorg-20

Yeah, I got the socket for the block drain, though I think a decent enough job could be done without pulling it. As far as distilled water, I agree if I can pop the block drain I'd have no problem running a hose through it. I have well water but I've had it tested and it's not hard, but I would flush the system with distilled before filling with antifreeze/distilled mixture.

I've got a Dodge Ram as well, which I did a radiator/water pump on recently and used the Mopar coolant, so I'm gonna grab another gallon of the Mopar coolant and use it in the Jeep so they both use the same.

I've also ordered the themocure flush.

Thanks for the link to the funnels, thats a pretty trick setup!

 

[hardtailpan]

I guess if I just read the FSM better I'd have my answer. Direct from FSM:

CAUTION: MoparT Antifreeze/Coolant, 5
Year/100,000 Mile Formula (MS-9769) may not be
mixed with any other type of antifreeze. Mixing of
coolants other than specified (non-HOAT or other
HOAT), may result in engine damage that may not
be covered under the new vehicle warranty, and
decreased corrosion protection.

Bold by me.
That seals the deal.

 

[IAmTodd]

I just did a drain and flush last week when I did my water pump. Make sure you pull the block drain too. I pulled my heater hoses off and flushed them too. Some people get uptight about not using distilled water, but if you pull the block drain, open the radiator petcock, and the heater hoses, and let ‘er rip with a garden hose, it WILL all drain back out. Then I hooked up everything, and refilled with the Zerex GL05 mixed 50-50 with distilled water. That’s where having distilled actually counts.

And one of these type of funnel kits makes things way easier as well.
https://www.amazon.com/dp/B01A2CQSU6/?tag=wranglerorg-20

I did this exact same thing with mine but used a couple extra jugs of distilled water - hey, they're cheap! I have nice, clear G-05 flowing in there now. Don't forget a new rad cap if yours is original.