Fresh motor and new radiator: should I switch coolants?

[wheming]

So was wondering if one of those newer coolants would be better to run in Slugmobile's fresh motor since I had to install a new radiator at the same time. I know my 05 PT uses that orangey looking stuff if I remember right.
Was wondering if you tech heads think going to the new coolant or different coolant is a good idea. I think that stuff is like 100k mile rated too. But wouldn't want to if there was some type of incompatibility I don't know about.
Thanks!

[Force Fed Mopar]

I have been thinking of switch to a newer coolant also. The orange Dex-Cool stuff seems to be disliked by many. Not sure if the Chrysler orange is the same or not. I was thinking of trying the pink or blue stuff used by Honda and BMW (and maybe others too).

[turbo84voyager]

I would use the green ( if you can still get it) Otherwise use the all makes and models antifreeze, most are some type of extended life. The HOAT stuff that chrysler uses is a little more pricy and only a few companies make it and I dont see a benefit to using it unless that is what is in there. I would not recommend Dex-cool in anything unless a GM product that came with it. GM had a lot of issues start (intake leaks etc..) after switching to dex-cool. This is one of those areas where there have not been any problems in 2 decades on our cars so I would not change types.

[contraption22]

I use Prestone All-Make & Models, mostly because, that's what I had, and when I flushed the cooling system of my SRT-4, I didn't feel like having to stock two different types of coolant for all my vehicles. I even used the premix 50/50 stuff because I didn't like feel like mixing in the distilled water.

I think the main things to keep in mind is do not mix incompatible coolants, and flush every couple of years.

Other than that, our vehicles really don't have much of an issue with cooling system rot.

[turbo84voyager]

One recomendation is to always test the antifreeze freezing point even with new antifreeze. About 10 years ago I put a new 302 in a friends truck. Filled it with 50-50 prestone and nothing else. A few months later in the winter it froze enough to cause a freeeze plug leak. Bad antifreeze. We tested it afterwards and sure enough there was almost no freeze protection. Probabily one in a billion chance, but it can happen.

[wheming]

I know at one point Gus was using or had planned to use some fancy (and get this: pricey!) supercoolant. It was supposed to have better heat transfer and be slicker. I can't really remember if he ever did.

Thanks for the tips. I have never seen much problem with our cooling systems, but wondered if a switch still wouldn't be a good idea. Now is the only time when there is no residual fluid in the system. Even plan on flushing and shop vac out my heater core.

[contraption22]

I remember Gus talking about Evan's coolant back in the day. It's a waterless coolant that has good points and bad points.

On the plus side it has a super high boiling point, so you do not need to run a high pressure coolant cap. It also is known to keep the temp more consistent thoughout the entire system, reducing hot spots and the chance for detonation.

The cons are that it is not compatible with water. So the entire system needs to be perfectly dry and clean before adding the Evans stuff. Not a big deal with a brand new motor and radiator, as long as you can get everything out of the heater core, etc. But a PITA if you're setup is already assembled. And if you ever run into a roadside emergency, you can't just throw in water without throwing away your very expensive Evans coolant. Also it is not as good at transferring heat as water, or 50/50 water/conventional coolant. So if your cooling system is marginal to begin with, this will make it worse. Generally, it is recommended to increase the vehicle's cooling capacity in order to run this stuff, which for a musclecar guy or a more mainstream performance vehicle, is a little easier, but for our cars, where space is preciuos, and we usually will give up some radiator capacity to run intercooler plumbing, it's not a great option.

One person in the community was having trouble keeping his L-body cool with this stuff.


I know at one point Gus was using or had planned to use some fancy (and get this: pricey!) supercoolant. It was supposed to have better heat transfer and be slicker. I can't really remember if he ever did.

Thanks for the tips. I have never seen much problem with our cooling systems, but wondered if a switch still wouldn't be a good idea. Now is the only time when there is no residual fluid in the system. Even plan on flushing and shop vac out my heater core.

[wheming]

Very good info!
Yes that was it, I remember now the incompatibility with water now.
I think I'll pass on that stuff.

[Tbird232ci]

My Trans Am has had Dex-Cool since it came from the factory. I got the car with 131K miles on it, and from what the previous owner told me, it has never been flushed. Only tested and topped off. I lost a head gasket due to a leaking upper radiator hose shortly after getting the car, and I did the tear down. Not a single hint of added corrosion or anything of the like on the car, even with the aluminum heads. I think the biggest issue with ANY coolant is the last of maintenence. Any coolant can develop a charge and become corrosive, and any coolant can get contaminated or deteriorate.

Unless knowledge: GM dealers would put in a red "clay" tablet or two in the radiator during the first service to help stop any leaks. The engine bays were cramped and it was hard to diagnose a leak, so they used the clay to prevent any leaks and save the hassle.

[supercrackerbox]

I also looked into the Evans stuff, and read that it was flammable. I don't know if that's true or not, but it was mentioned several times. What I do know is that it's expennnsive. Something like $45 a gallon. Which isn't terrible if it works, but it seems like I'm draining my cooling system for one reason or another about every summer.

Personally, I plan to run straight water in the GLHS with a bottle of Redline water wetter for corrosion protection. Since the GLHS will be kept indoors and only come out in the summer, I'm not worried about freezing.

[contraption22]

My Trans Am has had Dex-Cool since it came from the factory. I got the car with 131K miles on it, and from what the previous owner told me, it has never been flushed. Only tested and topped off. I lost a head gasket due to a leaking upper radiator hose shortly after getting the car, and I did the tear down. Not a single hint of added corrosion or anything of the like on the car, even with the aluminum heads. I think the biggest issue with ANY coolant is the last of maintenence. Any coolant can develop a charge and become corrosive, and any coolant can get contaminated or deteriorate.

Unless knowledge: GM dealers would put in a red "clay" tablet or two in the radiator during the first service to help stop any leaks. The engine bays were cramped and it was hard to diagnose a leak, so they used the clay to prevent any leaks and save the hassle.

I think most of the issues with dex cool originated from people mixing incompatible coolants to top off.

---------- Post added at 02:54 PM ---------- Previous post was at 02:52 PM ----------




Personally, I plan to run straight water in the GLHS with a bottle of Redline water wetter for corrosion protection. Since the GLHS will be kept indoors and only come out in the summer, I'm not worried about freezing.

You may want to look into a lower temp thermostat, and a higher temp pressure cap if you do that. Once water gets close to it's boiling point, it creates steam pockets in parts of the cooling system that get warmer than your temp gauge is reading.

[turbo84voyager]

I think most of the issues with dex cool originated from people mixing incompatible coolants to top off.


Completely agree here. I have seen countless cars where they have mixed and it turns into orange sludge. I have seen a lot of shops drain out the system when doing intakes on 3.1 and 3.4's and think they are doing a favor by refilling with green. Well the problem is many dont flush the system so there is still coolant in the heater core, parts of the block, etc.

The only thing that scares me about dex-cool is up until the time they started using it, how often did you ever hear of 3.1's or even the older 2.8's needing intake gaskets, almost never. Then all of a sudden there was a problem.

Another problem is Dex-cool (according to tests) is effected by exposure to air and will break down. I need to change the dex-cool in my 01 GTP. The car only has 5K on it but it is 12 years old. It tests good and looks good but I dont want to take any chances. In this case I am going to refill with GM brand dex-cool.

---------- Post added at 04:24 PM ---------- Previous post was at 04:18 PM ----------


Personally, I plan to run straight water in the GLHS with a bottle of Redline water wetter for corrosion protection. Since the GLHS will be kept indoors and only come out in the summer, I'm not worried about freezing.

Why not just run regular coolant (50-50). It also raises the boiling point. Our cars dont have issues with regular green or all makes and models coolant so I dont see a reason not to use it. Back in the early 80's when some of our cars were new, some of the antifreeze may not have been the best because might not have been properly designed for aluminium heads but those problems have been resolved decades ago

[black86glhs]

These aren't a sealed system like the newer ones, so don't use dex-cool. The overflow is open to the air and that is what will cause issues. The coolant works fine, but only in a fully closed system( the overflow is also pressurized).

[Force Fed Mopar]

If you just run water and and additive, use distilled water if possible. Has no minerals in it to leave deposits/cause corrosion. I believe this is something done from the factory and rarely gets done afterwards.

[roachjuice]

If you just run water and and additive, use distilled water if possible. Has no minerals in it to leave deposits/cause corrosion. I believe this is something done from the factory and rarely gets done afterwards.

Green coolant and Garden hose water ftw. :D

[fishcleaner]

One person in the community was having trouble keeping his L-body cool with this stuff.
That would be me. I was running hot (Evans will run 15* hotter than water but that's not a problem because it's boiling point is something like 400*) so I drained the Evans out and put
in standard stuff and the car still ran hot, maybe hotter than the Evans, so I'm not blaming the Evans, in fact I drained the water and put the Evans back in it. The down side of
the Evans is 1. cost, 2. it runs hotter, but in theory the engine is more efficient hotter. The upside is 1. you will never boil over, 2. no steam build up in the head which means no hot
spots and in fact I have yet to hear a pinging in my car. 3. Nothing will corrode even with dissimilar metals. 4. With the little expansion it has, you won't blow any hoses.

If your car is a toy, I would get it, it hasn't been a problem with draining it and putting it back in, just keep the jugs around to re-use it. For a street/strip car get the NPG+, I got mine
from a local shop and it was $38 a gallon, that is high but its a lifetime product.

[supercrackerbox]

Why not just run regular coolant (50-50). It also raises the boiling point. Our cars dont have issues with regular green or all makes and models coolant so I dont see a reason not to use it. Back in the early 80's when some of our cars were new, some of the antifreeze may not have been the best because might not have been properly designed for aluminium heads but those problems have been resolved decades ago

Primarily because the local(ish) drag strip prefers you don't run antifreeze in case of a mishap; it's harder to clean up. But also, while antifreeze raises the boiling point, it also slightly reduces the coolant system's ability to transfer heat. The pressurized system will keep the boiling point high enough.


You may want to look into a lower temp thermostat, and a higher temp pressure cap if you do that. Once water gets close to it's boiling point, it creates steam pockets in parts of the cooling system that get warmer than your temp gauge is reading.

I plan on that.


If you just run water and and additive, use distilled water if possible. Has no minerals in it to leave deposits/cause corrosion. I believe this is something done from the factory and rarely gets done afterwards.

Oh I plan on it that as well. There's also theories about running a ground strap from the radiator to the frame, which I need to research more.

[phantomrt]

In all my automotive experience, I do not see any clear benefits of one antifreeze to another. Just maintain the cooling system--you know, change the fluid every 5 years or so and you are good to go with whatever you use. I prefer green over the orange, yellow, pink, etc stuff simply because it is easy to identify. When you get the orange stuff mixing with oil, it isn't nearly as obvious. But the color itself doesn't mean anything. It can be dyed any color the manufacturer wants to.

Use distilled water--that is pretty important in my opinion. What coolant does evaporate will not leave minerals behind.

As far as the mixing ratio goes, you do want a 50/50 mix in the northern climates unless you don't mind draining your cooling system every fall. Even then, maximum efficiency cooling systems are not as important in the cooler climates, so there is no real need to run more water for a bit more effective cooling.

As far as boiling point goes, antifreeze raises the boiling point, but not by much--somewhere in the tune of 218 degrees per the last time I had it happen. They still rely on pressurization of the cooling system in order to prevent boiling. I can't recall the ratio of boiling point increase to PSI of pressure, but the normal 16 PSI radiator cap will take it to 250 degrees, and at which point you are going to have other problems.

My Dad's 2000 Impala had the original DexCool stuff in it for about 9 years / 110,000 miles with zero issues until the typical GM intake manifold gasket problem occurred, but those plastic gaskets will fail no matter what coolant you keep in there. They fail because the plastic deteriorates / breaks up / etc and without the plastic chassis of the gasket to support the O-rings, they leak. And those intakes are barely torqued down, probably to prevent crushing of those POS gaskets. In addition, a bit of corrosion at the gasket surface doesn't help things much. That can simply be caused by the PH of the coolant going out of balance because people never change their coolant. Felpro's metal / rubber gaskets are the way to go. It is just like General Motors' engineering to let the aftermarket produce parts better than their own. That usually doesn't happen in the automotive world.

[Reaper1]

Dex-Cool breaks down over time and becomes acidic and attacks aluminum stuff. I've seen it lots and lots of times. The problem stems from people not doing maintenance, but I don't like the stuff anyway. Just use the "universal" Prestone, or Peak. You can still get the green stuff, but I wouldn't do it...just in case you find yourself in a bind and NEED to use Dex-Cool in an emergency (but get it out and flush the system ASAP).

Also, I agree with using distilled water. I also throw in a bottle of Red Line "Water Wetter", as I tend to run a lower ratio than 50-50 coolant.

[shackwrrr]

I just use safetykleen kamelion from work. Pre mixed and ready to go.

[black86glhs]

I just pee in my radiator.

[Force Fed Mopar]

I just pee in my radiator.

That's just nasty...

[black86glhs]

That's just nasty...Yep..