I am getting close to firing my motor.....I hope....and i am making a list of the fluids I need. I am not sure what coolant to use.

I don't know what was used previously with this engine....it is 99 with 34k miles so I am guessing it probably has what it came with from the factory

I know mixing coolant can mess things up so I want to be careful with this. What coolant did you guys use and what is the best way to flush the LS1
Thanks guys

 

get the stuff from the parts store that mixes with both(so it doesn't matter if you mix the 2 or not)

-Matt

 

stay away from the Dex-cool, run the stuff that is safe for both colors

 

thanks guys

does this coolant have a name......I am looking through the brands at advanceautoparts and don't quite see it

I'll keep lookin though

 

use the G05 stuff. works great! would never go back to dex.

 

I ran water and water wetter for all of last summer, but then I put coolant in it for the winter. I bought mine at advance autoparts. It was prestone, it was the extended life stuff 5yr 50 thou miles, I was looking for the old green stuff and could not find it anywhere. If you look at the jug of prestone it will probably say right on it that it mixes with anything, I think they changed to the extended life stuff and no longer sell the good old green. Just make sure you stay away from GM`s own dexcool, it is not cool at all. I would run the motor for a little while on water, I changed my water probably 3-4 times before I put coolant in it and it always came out tinted orange because that dexcool sludge/coolant was stuck in the motor somnewhere. Also don`t forget to fill the motor via the upper radiator HOSE, if you fill via the radiator cap the motor will not fill and will overheat before the theromostat opens.

 

Dex Cool is made for longevity and for aluminum as it was designed for the Corvette. If it is good for the Corvette it should be good for my LS1 swap. I have a C5 and use Dex cool and now I have an LS1 in my El Camino so it makes sense to keep them the same.

The point with Dex is that it is suppose to be better for aluminum blocks as it isn't as abrasive as the green stuff. I know of someone mixing Dex and Green and the whole coolant gelled up like jello. It took them a while and many flushes to get most of it out of their Camaro's coolant system.

I personally think that Dex is ok, green is OK, and generic stuff is OK. I just chose to go with what GM recommends and also to keep my two cars insink using the same stuff.

(Note: I have the aluminum LS1 and installed a aluminum radiator so it made sense to use Dex Cool)

 

I have a brass/copper radiator. The dex cool would destroy the solder on the radiator.

 

In my past experiences the dex cool is very hard on seals in the waterpump and on intakes. I know on a ls1 water doesnt flow through the intake but figured I would throw that in. It eats up seals for some reason. I prefer the good old green stuff. If you compare the two in a feel test the green has alot more lubricating properties than the dexcool, it feels very dry for some reason. I use a blue coolant made for bmw's as I work for them and can get it for nothing. It is 5 year coolant, and is very easy on aluminum. Just my 2 cents, hope it helps. Josh

 

If you have worked in a shop every day, You know how nasty dex can get.

 

the advance brand is fine and cheaper. you dont need a brand name , just if you want premixed or not. and as far as coolong system lubricants, there is an additive you can add. i dont remember the name but its in a small white jug bythe lucas stuff in advance. that stuff works good as a lube and is suppossed to be safe on aluminum.

 

I have seen GM dexcool turn into sludge in a couple different cars even when people had never added any other brand of coolant to the cars, in fact I think that a couple of them never even had to add coolant. From what I heard GM was having a lot of problems with their dexcool turning to sludge, so I avoid it like the plague. I have not heard of any problems with any of the aftermarket extended life coolants though.

 

I use the orange stuff. I forget what it is, I think its the prestone.

 

Dexcool is crap - I've seen it eat a radiator in 80k, and then another one just under 20k later on the same Suburban.

I run the new 'compatible with anything' Prestone. It's green but it says it's compatible with the red stuff...I'm sure my LS1 was very dry of the old red stuff (it sat long enough to get dirt caked in the cylinders!) but I figured it was an easy 'safe' choice to make. On top of that, it seems to be the only Prestone left around here - all of the stores have pallets of the new stuff, and little-to-none of the old standard green Prestone.

With a bottle of water wetter and a 160* stat, my fans don't even kick on in 100-105* heat on the way home. Yes, I need to get them reprogrammed

 

http://www.imcool.com/articles/antif...l-macs2001.htm

MACS 2001: GM and Texaco “Bare All” about DEX-COOL®
As in the past, the MACS 2001 Convention and Trade Show in Orlando provided some very interesting and helpful air conditioning information. However, the sleeper presentation at this show was not about refrigerant, but—of all things—engine coolant! (Sleeper does not refer to making you sleepy; it was anything but boring.)

Marketing departments of major consumer goods manufacturers are known for their attempt to conceal even a shred of negative publicity about their products. You can’t blame them; you do the same in your business. That’s why it was refreshing to witness a candid GM/Texaco presentation about DEX-COOL coolant and its related field service problems. I give the big guys credit for even bringing up the subject because, well, let’s face it, there are not a lot of kind words being spoken about this coolant at automotive service shops today. (Especially at radiator shops.)

Left: 14-Minute GM Training Video is now available to help technicians service known cooling system contamination problems in specific GM vehicles.

GM’s Jay Dankovich and Equilon Enterprises’ (Texaco) Stede Granger directed a 2-year study of thousands of DEX-COOL cooled vehicles. Armed with the results, they really didn’t have anything bad to say about the coolant. In fact, they strongly defended the product’s reputation. What they revealed to the audience is that specific models of GM vehicles have specific cooling system contamination problems. And essentially, that DEX-COOL is not the culprit!
Their presentation started with a 14-minute video that is now being circulated to technicians at GM dealers nationwide. In the video, GM’s trainers succinctly described the problems that have been found and the corresponding corrective actions to be taken by technicians.

Suggestion. This video is a “must see” for all technicians considering themselves antifreeze/coolant experts. Without this information, your cooling system service knowledge of late model GM vehicles is severely limited. Seriously!
Fortunately, you can buy the video for only $10 (plus S&H). Call MSX International of Auburn Hills, Michigan at 800-393-4831. Ask for the DEX-COOL Video: “Understanding Radiator Cap and Cooling System Contamination.” Part number: RADCAPK. Immediately following this article is a report on this training video by John Brunner, recently retired GM field service representative.

What was said at the presentation? Besides the video, Jay and Stede included their personal observations about the study. At the end, they fielded several questions from the audience. Here’s a recap of their entire presentation.

1. Keep the cooling system filled. In fact, fill the reservoir bottle to “Hot” level when the system is cold. Problems arise when a system’s coolant level is not maintained. (Fleet vehicles receiving regular maintenance, and with reservoirs kept slightly above normal, do not show signs of contamination. This even applies to the specific “problem” vehicles.)

2. The coolant problems found in this survey were caused by system contamination, and not due to the breakdown of DEX-COOL.

3. Check and keep the pressure cap clean and functioning. A contaminated and/or malfunctioning cap causes low coolant levels, which in turn causes overheating and a greater loss of coolant: the notorious vicious cycle. No matter what the vehicle, if the cooling system acts suspiciously, test the pressure cap.

4. On the ST vehicle models mentioned in the GM DEX-COOL video, you “must” replace all suspect radiator caps, especially those with a Drop-Center design, with a Stant Model 10230 or 11230 (Spring-Center type). (Just do it.)

5. Make sure that the coolant is at a 50-50 mix. Often, the flush water was not being removed from the engine block. Consequently, when a 50-50 mix is added to the system the resultant mixture could approach 30-70. Like any fluid that has been diluted beyond its recommended levels, the lowered level of inhibitors will not be able to protect the coolant system effectively. Low levels of inhibitors can cause pitting on aluminum surfaces and general corrosion of cooling system metals.

Left: Drop-center, “vented” radiator pressure cap. GM found this cap (like the Stant 10231) to be less helpful than a Spring-center cap (shown below) in controlling the formation of contaminants in the cooling system. If contamination forms, the debris fouls the valve and restricts its ability to seal. In turn, the coolant boils at a lower temperature. Coolant loss is accelerated and so is the accumulation of contaminants.

Left: Spring-center, sealed radiator pressure cap (like the Stant 10230). This is the preferred cap for GM applications that are more prone to accumulating cooling system contaminants.

6. A safe method of achieving a true 50-50 mix is to first determine the actual capacity of the system (use the owner’s manual). Then add 50% of “that” amount of undiluted DEX-COOL (or any coolant), and top it off with water.

7. Mixing a “green” coolant with DEX-COOL reduces the batch’s change interval to 2 years or 30,000 miles, but will otherwise cause no damage to the engine. In order to change back to DEX-COOL however, the cooling system must first be thoroughly drained and flushed.

8. Bacteria cannot live in a hot, Ethylene Glycol environment and is therefore not a threat to DEX-COOL.

9. While there have been intake gasket failures on CK Series, V8 powered vehicles for various reasons, DEX-COOL has never been found as a cause.

10. Use a refractometer to check the condition of DEX-COOL. Its inhibitor package is strong enough that if the batch still provides proper freeze protection, it is probably still providing proper corrosion protection as well.

11. DEX-COOL can handle the minerals in hard water better than silicated conventional chemistry coolants. Drinkable water is suitable for top off.

12. In ST Blazer applications where the radiator cap is mounted at an angle to the ground, the vehicle is more susceptible to radiator cap contamination and its related problems. The Stant 10230 is a wise choice for these vehicles. $$$

Below are findings from local Northern California cooling system service shops that supplement the article above.

Left: A check with local cooling system shops revealed this cap. It's from a mid-90’s Blazer with about 50K miles.
Below is the neck.


Left: This cap is from a later model Blazer with under 15K miles (notice the onset of corrosion). The cause was not verified, but appears to be iron oxide. If so, the system will need to be chemically flushed.
Left: Notice the buildup in the coolant reservoir. This too appears to be the iron oxide problem. The system can be cleaned, and if not plugged excessively, the radiator can be salvaged.


Editor: Soon you will be able to check in with “current” radiator and a/c industry vendors on the web at: www.imcool.com/buyersguide/.
Vendors: If you would like to be listed as a vendor to the automotive (and Heavy Duty) radiator and A/C service industry, please call, fax, email or fill out the form on the imcool.com web site. Look for Buyer’s Guide Data Entry Form.
Your cost to be listed on the web site and in the 2002 Annual Guide is only $12. For that, you also get a subscription to Cool Profit$ Magazine. In addition, your web listing will be maintained for free (name, contact, address, phone, email, URL, etc.). One heck of a deal.

 

http://www.getahelmet.com/jeeps/maint/dexcool/

Here is more information about Dex Cool.

Let's look at the facts then decide if Dex Cool is crap. I have a 6 year old C5 with Dex Cool, no leaks, no sludge, no problems.

http://www.imcool.com/articles/antifreeze-coolant/CPM-52-DEXArticle-Excerpt.pdf#search='dex%20cool'

Here is a article on a class action lawsuit going on however there is no factual scientific proof Dex Cool is the issue, just hear say and emotional finger pointing. I personally need proof.

 

Well, my personal thought is the old smoke and fire thing. There seems to be many accounts of cooling systems having problems with Dex Cool that are not showing up with other coolants. Personally I have a hybrid system that has an aluminum motor with a brass radiator. Conventional coolants seem to work just fine protecting the system and cooling the car, so why should I take a chance on a product that appears to be so unforgiving? Especially if there is no significant benefit. Based on what I have read here and elsewhere there will be no Dexcool in my rig.

Pat

 

Great Pat! I hope everyone makes a decision that is right for them. What I also hope is that everyone find out the fact first before making a decision. Many people just go off of hear-say, I knew a friends uncle who..., without finding out the facts.

My decision is I am going to stay with Dex Cool. My conversion I also changed to a aluminum radiator so now the whole system is one type of metal which is suppose to be the reason to use Dex Cool.