New here and have a question.

[NathanY]

This is a great site. I have been lurking for a long time and decided to sign up today because I am starting a project on a 1997 1500 SB Regular cab 4.3L. My water pump went out the other day so I am in the process of replacing it. When I noticed it was leaking I knew that it would have to be replaced, so I drained all the antifreeze out of it, pulled the thermostat, flushed real good and added just water and two bottles of Prestone HD radiator flush. Drove it around for a couple of weeks, making sure to keep the water level full since it was leaking. Yesterday, I pulled the water pump and flushed the block real good to make sure all the rusty looking water and crud was out of the system. It took about thirty minutes to get clear water, but I am confident the block is clean. I back flushed the radiator until clear water came out of it. I am sure that my system is now clean and clear of all the DexCool antifreeze and any remaining radiator flush that was still in the system.

Now my question, when I put this all back together, what antifreeze should I use? Should I use the pink DexCool or just use any extended life antifreeze like the yellow Preston or Peak, or should I use regular green antifreeze? I did a search of the forums and could not find and answer to this question. I would like an expert opinion. I have had good luck with the Napa extended life yellow antifreeze in Fords and the heavy equipment that I work on, like skid steers, Mack dump trucks, loaders, and excavators, but have never used it in a Chevrolet where DexCool is recommended.

Thank you for your help and thanks for having a great site dedicated to the GMT400.

 

[barebones 1500]

I prefer the good o'le green antifreeze. I have heard too many stories about the dexcool destroying parts. As long as you have all the old flushed out you can put whatever you want in there.

 

[Southern Pride]

Do NOT use the orange dex cool! It's been proven to gunk up and cause all kinds of troubles. I go to autozone and get the green prestone stuff!!! Make the switch bro and good decision signing up there is quite an abundance of all kinds of info on here. WELCOME!!

Here you will find great info since the knowledge is all concentrated to GMT400's, you don't have van owners telling you what fluids to use. I've switched to the green and it has worked great 95 350 TBI

Griffin

 

[NathanY]

When the truck was new it came with DexCool and the previous owner also used the DexCool. He gave a jug of it when I bought the truck from him.

SP, when you say the green Prestone stuff, are you refering to the regular green antifreeze or the light green extended life?

 

[RHamill]

When I had my intake gasket replaced, the guys at the shop found a jug of extremely cheap ****** green antifreeze I bought just to top off my radiator to limp it to the shop, and they poured that in there when they were done..

I was hoping they would flush it and put the good green stuff in there..

 

[Southern Pride]

When the truck was new it came with DexCool and the previous owner also used the DexCool. He gave a jug of it when I bought the truck from him.

SP, when you say the green Prestone stuff, are you refering to the regular green antifreeze or the light green extended life?

Alot of these gmt400's had dexcool in them a while back, because GM called for it, and later Recalled it. When I bought mine in 2002 it had dex cool. My water pump went bad and like you I got on fullsizechevy or whatever and the guys were telling me how bad dex cool is. As far as the prestone goes, it's completely up to you man. Want to pay extra get the extended life or the regular green will be absolutely fine. It's actually a good thing your pump went bad or else you wouldn't have flushed and rid yourself of the dexcool crap. It's been a while since I did mine but I remember getting the prestone yellow jug and doing the 50/50 mix.

 

[Solid94]

Yea I heard the dex cool eats up parts faster but I just have been using it since it's what came from the factory. All I know is run one or the other. Ever mix it and it turns into sludge. Don't ever waste the money for the pre mixed 50/50 antifreeze. It's just water and antifreeze. Just buy the regular and pour it in the. Fill the empty jug back with water and pour the water in.

 

[RHamill]

Yea I heard the dex cool eats up parts faster but I just have been using it since it's what came from the factory. All I know is run one or the other. Ever mix it and it turns into sludge. Don't ever waste the money for the pre mixed 50/50 antifreeze. It's just water and antifreeze. Just buy the regular and pour it in the. Fill the empty jug back with water and pour the water in.

Is that how much the radiator takes from empty? 2 full jugs (1 antifreeze and 1 jug of water) I know what you are saying about mixing it that way, but is that a perfect way to mix it in the radiator?

 

[darren250r]

Yea I heard the dex cool eats up parts faster but I just have been using it since it's what came from the factory. All I know is run one or the other. Ever mix it and it turns into sludge. Don't ever waste the money for the pre mixed 50/50 antifreeze. It's just water and antifreeze. Just buy the regular and pour it in the. Fill the empty jug back with water and pour the water in.

You need to be using distilled water. Tap water will give your system a lot of corrosion and deposits.

 

[Z71Sierra]

You need to be using distilled water. Tap water will give your system a lot of corrosion and deposits.

^^This^^

You would think that auto parts store would sell the water as well, but I guess that's why premix is so popular. As far as mixing it goes I always have an empty jug that I fill half full with coolant, then top off both jugs with water. This way it's mixed before it goes in. I dunno if it matters, just my .02