Coolant

[HiHoeSilver]

Definitely none of the old mix still around. Get the specs for the current mix, like Steve said, and can double check at RA for the Dex-Cool listed there and buy it at a store or auto parts shop you trust. Follow all directions to the letter. Distilled water mix is the best so if the numbers are close, like Nate says, the pre mix could be the way to go. Is there a shelf life difference between pre mix and full strength?

Should not be a shelf life difference. My point on price was that usually they are similar, so 1 gallon of concentrate + 1 gallon of water will be less costly than 2 gallons of pre-diluted.

 

[swathdiver]

Is there a shelf life difference between pre mix and full strength?

You mean after opening the bottle? Yes, but I don't remember! HA! I have that same bottle as Nate somewhere in the garage.

 

[OR VietVet]

dexcool or equivalent, flush it annually. I don't care if they say it's good for 5 years that's just asking for it. It's not like it's a high cost maintenance item, better safe than sorry....

Plus, a maintenance item like that is something you can plan on ahead of time and know the cost of. Instead of letting it go too long and then dealing with a surprise repair and not knowing the total cost.

 

[JonnyTahoe]

Yup. WalMart, any autoparts store, ranch store, etc.

This is a new jug as of about a month ago. Date on the back sticker is 2019. Look on the bottom of the back side of the container and you should see what appears to be a Date code but it's not the actual date. mine is 02 06 31

 

[JonnyTahoe]

Should not be a shelf life difference. My point on price was that usually they are similar, so 1 gallon of concentrate + 1 gallon of water will be less costly than 2 gallons of pre-diluted.

Directions on back label of Prestone Dexcool 50/50. Top off: Fill overflow tank to Max level with 50/50 Prestone. Drain and Fill: 'Requires 2 gallons of Prestone 50/50'. Only the Concentrate has mixing directions on the back label.

 

[OR VietVet]

It has been accepted in the industry for years and years that while you can run straight coolant it is better to mix 50/50 with either Dex or regular coolant for optimum results. Water is a better heat dissipator than straight coolant is. Coolant absorbs heat at high temps but water is even a little better so when mixed it all does a better job. If you watch NASCAR they run water in those engines. If straight coolant was better they would run it. Kind of like some cleaning fluids work better mixed with water than straight cleaning fluid.

 

[Fless]

Directions on back label of Prestone Dexcool 50/50. Top off: Fill overflow tank to Max level with 50/50 Prestone. Drain and Fill: 'Requires 2 gallons of Prestone 50/50'. Only the Concentrate has mixing directions on the back label.

I might agree with a couple of gallons of 50/50 IF you're just letting things drain and you're not doing a good job of draining the block. Really, though, while you're at it why not flush the whole thing and have all-new antifreeze mix instead of mixing new with old?

The listed capacity for the 5.3L V8 cooling system is around 16 quarts. That's 4 gallons for those of you who are mathematically challenged. A 50/50 mix would take 2 gallons of straight antifreeze, not prediluted. Personally I like to start with about a 60% antifreeze mix in the entire system in case I need to add just water in a bind.

 

[Livebai8]

I drive a 2005 Tahoe z71. I Have about 160k miles on it.

What coolant should I be using in it? I know it calls for dex-cool but I’ve read on other GM and Chevy forums that it’s bad and eats away seals and gaskets over time.

So when I bought it I put in a new radiator and water pump and filled it up with Peak 50/50. I haven’t had any issues with it. It’s been running great for the past year and it looks just as clean as the day I put it in.

Recently, I had a small leak. Turns out my thermostat housing wasn’t tightened down to spec. That was my own fault. My mechanic noticed that I was using the wrong coolant though and mentioned that I should be using dex-cool - so here I am lol. He claims that GM has a new dex cool formulation that doesn’t eat away at seals and gaskets and recommended that I switch.

Is there truth to this? Should I stop using Peak 50/50 and switch to the new dex cool?

Any insight or wisdom would be much appreciated.

Thanks

I had my system flushed several years ago. I'm in the Houston area so...yesterday was low 30° to 50°...today it's about 72°!! Anyhow I've only used the 50/50 coolant since the flush and I haven't had any issues.

Sent from my SM-N920T using Tapatalk

 

[HiHoeSilver]

Directions on back label of Prestone Dexcool 50/50. Top off: Fill overflow tank to Max level with 50/50 Prestone. Drain and Fill: 'Requires 2 gallons of Prestone 50/50'. Only the Concentrate has mixing directions on the back label.

I was just using 2 gallons as example to illustrate the cost. The 5.3 needs 4. My point was it's usually much cheaper to buy full strength and dilute it yourself.

I might agree with a couple of gallons of 50/50 IF you're just letting things drain and you're not doing a good job of draining the block. Really, though, while you're at it why not flush the whole thing and have all-new antifreeze mix instead of mixing new with old?

The listed capacity for the 5.3L V8 cooling system is around 16 quarts. That's 4 gallons for those of you who are mathematically challenged. A 50/50 mix would take 2 gallons of straight antifreeze, not prediluted. Personally I like to start with about a 60% antifreeze mix in the entire system in case I need to add just water in a bind.

Agreed on the flush. Here's my method, that avoids needing to be crazy on draining (like removing the block plug), and is easy on math (knowing how to divide the system capacity by 2):

1. Drain that puppy from the lower radiator hose AND the hose from the pump. Put it back together and fill it with the garden hose.

2. Run it. Drain it. Fill it. Run it. Drain it. You get the idea. I do it until it's draining good and clean. Maybe 6-8 times. Anything left in the system after the last drain will be "clean" water.

3. Add full concentrate coolant based on 50-60% of the system capacity.

4. Add distilled water to full.

This removes any guess work, as you know the system capacity and exactly how much full concentrate coolant you put into it. The rest is obviously water, either from your garden hose or your distilled final fill.

 

[JonnyTahoe]

I might agree with a couple of gallons of 50/50 IF you're just letting things drain and you're not doing a good job of draining the block. Really, though, while you're at it why not flush the whole thing and have all-new antifreeze mix instead of mixing new with old?

The listed capacity for the 5.3L V8 cooling system is around 16 quarts. That's 4 gallons for those of you who are mathematically challenged. A 50/50 mix would take 2 gallons of straight antifreeze, not prediluted. Personally I like to start with about a 60% antifreeze mix in the entire system in case I need to add just water in a bind.

I just replaced my Radiator hoses a month ago. Unless you have a lot of rust in your cooling system in which case a complete flush would make perfect sense. I had decent coolant already and it was less than ideal working conditions so no need for a complete system flush just a drain and fill.