2007 Chevy 1500 with 5.3L engine

[Gary Fowler]

I was going to flush out the old anti-freeze and replace since it is over 6 years old. I started looking at how to drain it, couldn't get the bottom radiator hose off, looked for and found the radiator petcock but instead of finding the typical screwed plug for the petcock, it has a weird bulb looking thing in the middle of a plastic plug. I had no idea on how to remove it, so I just did a check with the anti-freeze and it tops out on my freeze protection/boilover protection @-47F which is as high as the tester goes. It says 50/50 solution is good for -37.
Anyone know how to remove the pet cock so I can drain the radiator. The truck only has 47K miles on it and the mileage between changes is 150K so mileage wise it is still good, just timed out just like my oil changes. I have already bought 2 gallons of Prestone anti-freeze that says it works for all colors but it isn't Dex-cool as GM recommends. Anyone of the opinion that I should return it and get the Dexcool (orange color)

 

[k0ua]

I was going to flush out the old anti-freeze and replace since it is over 6 years old. I started looking at how to drain it, couldn't get the bottom radiator hose off, looked for and found the radiator petcock but instead of finding the typical screwed plug for the petcock, it has a weird bulb looking thing in the middle of a plastic plug. I had no idea on how to remove it, so I just did a check with the anti-freeze and it tops out on my freeze protection/boilover protection @-47F which is as high as the tester goes. It says 50/50 solution is good for -37.
Anyone know how to remove the pet cock so I can drain the radiator. The truck only has 47K miles on it and the mileage between changes is 150K so mileage wise it is still good, just timed out just like my oil changes. I have already bought 2 gallons of Prestone anti-freeze that says it works for all colors but it isn't Dex-cool as GM recommends. Anyone of the opinion that I should return it and get the Dexcool (orange color)

Gary I don't know what to tell you about the petcock, but if you google Dexcool, There sure are a lot of horror stories about it.

Well, the official bulletin GM sent out says this:

Rust in Cooling System, Heater Inoperative, Blows Cold Air, Engine Overheats (Flush Cooling System) #99-06-02-012D
Rust in Cooling System, Heater Inoperative, Blows Cold Air, Engine Overheats (Flush Cooling System)
1996-2000 Chevrolet and GMC S/T Models (Blazer, Jimmy, Sonoma, S10 Pickup)

1998-2000 GMC Envoy

1996-2000 Oldsmobile Bravada

with 4.3L V6 Engine (VINs W, X -- RPOs L35, LF6)

This bulletin is being revised to include additional model years. Please discard Corporate Bulletin Number 99-06-02-012C (Section 06 -- Engine).

Condition
Some customers may comment that the heater is inoperative, blows cold air, engine may exhibit an overheat condition or the coolant reservoir has rust in it.

Cause
Vehicles equipped with DEX-COOL® coolant, which may have been operated for extended periods of time with a low coolant level, usually in excess of 32,000 km (20,000 mi), may be susceptible to the formation of a rust-like material in the cooling system.

Correction
Flush the cooling system using the repair procedures that follow.

Parts and equipment required/suggested for this correction are listed below.

1 each *Prestone® Flush and Fill Kit #AF-KITP U.S. (#00050 in Canada). This kit can be obtained from your local parts supplier and can be used on all vehicles repaired under this procedure. Save it after performing the repair, as it is reusable.
1 each *Prestone® Heavy Duty Cooling System Cleaner, GM P/N 12346500 - 1 per vehicle. This cleaner is in powder form and contains a neutralizer. Do not substitute other cleaners. The diluted cleaners that are available in liquid form are not recommended for this repair.
5.7 L (6 qt) of 100% (non-diluted) DEX-COOL® coolant (GM Spec 6277M).
1 each new thermostat, GM P/N 12563335.
2 each new radiator cap, GM P/N 15075565.
1 each *Prestone® yellow funnel. This funnel can also be obtained from your local parts supplier. It fits snugly into the radiator opening for an easy fill and is reusable.
----------------------
It goes on, but that is the part that covers this. As you see, it seems to have only happened in those vehicles where the coolant level has been allowed to drop and have over 20.000 miles. To say this is the fault of the manufacturer is like saying "I didn't check my oil, and when it was finally empty the engine blew up, so that's your fault."

Isn't that one of the fluids you check at least weekly?

 

[polarred21]

My 2002 5.3 engine was losing about 1 quart of anti freeze per month, enough to make the low coolant light come on when I park down hill. I had my mechanic pressure test it for leaks but found no issues. He changed out the coolant and it is orange color and put in these GM recommended tablets designed to help treat the system. Two years later and not losing any coolant anymore. May want to check on these tablets for your flush job. Good luck.

 

[Gary Fowler]

My 2002 5.3 engine was losing about 1 quart of anti freeze per month, enough to make the low coolant light come on when I park down hill. I had my mechanic pressure test it for leaks but found no issues. He changed out the coolant and it is orange color and put in these GM recommended tablets designed to help treat the system. Two years later and not losing any coolant anymore. May want to check on these tablets for your flush job. Good luck.

I am going on 48K mileage, original orange coolant, never added any and it is right on the full mark, looking in the radiator there is no corrosion evident. I have had no issues associated with the bulletin posted, just want to get rid of the old stuff and put in new but I am going back with Prestone (yellow I think but haven't opened the bottle yet) that says it is compatible with all colors, but I wanted to kind of rinse out the old stuff with clear water, I don't think I need a flush kit as there is no corrosion evident. I just need to figure out how to get the darned drain open. I hate to go prying on it since it is just plastic and I have never seen anything like it before. I am not even sure that I need to change it since mileage is so low but it has been in there for 6 years or more but it still looks just like the new stuff, no discoloration at all.
I did change out my 2009 RTV 900 and other than the tablespoon of yellow greasy waxy stuff that was around the neck, the antifreeze was just as green as the new stuff I put back in. I had 1/2 gallon from some previous use that I don't know what for, but it was more than enough to mix 50/50 with distilled water to refill the system. There is no evidence of a HST oil cooler on the radiator so no idea what the yellow junk was, I cleaned it out and wiped down all the hoses and refilled the overflow tank which was where the yellow junk was. Nothing in the radiator.
Edit: just remembered the previous use. It was when I replaced the radiator on my JD 332 garden tractor, it took 1/2 gallon to refill.

 

[Gary Fowler]

Isn't that one of the fluids you check at least weekly?

Maybe I should check more often, but unless it runs hot for some reason, I don't normally check radiator unless I am checking the oil and since non of my vehicles use any oil between changes, I don't check them very often unless I am heading out on a long trip, washer fluid is low or some other reason to lift the hood. Likely should be more maintenance minded but these newer engines that don't require any maintenance other than oil change when the computer tell you to, makes one get a bit lazy on the under hood checks. My vehicles are parked on concrete and I do look for any signs of leakage whenever I move them.

 

[The Fred]

Gary I don't know what to tell you about the petcock, but if you google Dexcool, There sure are a lot of horror stories about it.

Well, the official bulletin GM sent out says this:

Rust in Cooling System, Heater Inoperative, Blows Cold Air, Engine Overheats (Flush Cooling System) #99-06-02-012D
Rust in Cooling System, Heater Inoperative, Blows Cold Air, Engine Overheats (Flush Cooling System)
1996-2000 Chevrolet and GMC S/T Models (Blazer, Jimmy, Sonoma, S10 Pickup)

1998-2000 GMC Envoy

1996-2000 Oldsmobile Bravada

with 4.3L V6 Engine (VINs W, X -- RPOs L35, LF6)

This bulletin is being revised to include additional model years. Please discard Corporate Bulletin Number 99-06-02-012C (Section 06 -- Engine).

Condition
Some customers may comment that the heater is inoperative, blows cold air, engine may exhibit an overheat condition or the coolant reservoir has rust in it.

Cause
Vehicles equipped with DEX-COOL® coolant, which may have been operated for extended periods of time with a low coolant level, usually in excess of 32,000 km (20,000 mi), may be susceptible to the formation of a rust-like material in the cooling system.

Correction
Flush the cooling system using the repair procedures that follow.

Parts and equipment required/suggested for this correction are listed below.

1 each *Prestone® Flush and Fill Kit #AF-KITP U.S. (#00050 in Canada). This kit can be obtained from your local parts supplier and can be used on all vehicles repaired under this procedure. Save it after performing the repair, as it is reusable.
1 each *Prestone® Heavy Duty Cooling System Cleaner, GM P/N 12346500 - 1 per vehicle. This cleaner is in powder form and contains a neutralizer. Do not substitute other cleaners. The diluted cleaners that are available in liquid form are not recommended for this repair.
5.7 L (6 qt) of 100% (non-diluted) DEX-COOL® coolant (GM Spec 6277M).
1 each new thermostat, GM P/N 12563335.
2 each new radiator cap, GM P/N 15075565.
1 each *Prestone® yellow funnel. This funnel can also be obtained from your local parts supplier. It fits snugly into the radiator opening for an easy fill and is reusable.
----------------------
It goes on, but that is the part that covers this. As you see, it seems to have only happened in those vehicles where the coolant level has been allowed to drop and have over 20.000 miles. To say this is the fault of the manufacturer is like saying "I didn't check my oil, and when it was finally empty the engine blew up, so that's your fault."

Isn't that one of the fluids you check at least weekly?

That's so much BS. TRUE GM had 1.5 million gallons of dexcool go bad in 1996-97. The horror stories abound. The new Dexcool is excellent stuff.
Don't be afraid to use it.

Fred

 

[k0ua]

That's so much BS. TRUE GM had 1.5 million gallons of dexcool go bad in 1996-97. The horror stories abound. The new Dexcool is excellent stuff.
Don't be afraid to use it.

Fred

You know once it is on the internet, it lives forever.

 

[The Fred]

My 2002 5.3 engine was losing about 1 quart of anti freeze per month, enough to make the low coolant light come on when I park down hill. I had my mechanic pressure test it for leaks but found no issues. He changed out the coolant and it is orange color and put in these GM recommended tablets designed to help treat the system. Two years later and not losing any coolant anymore. May want to check on these tablets for your flush job. Good luck.

Water pump gaskets are most likely the cause of your loss, very easy job and quite common. It can be done in the yard. Use a mirror and a bright light to check for weepage where the pump meets the front of the block. Iron engine blocks (not aluminum) are more prone to leaking.
As I do maintenance on my equipment I convert them all over to Dexcool, it lasts much longer than the old green stuff. Mixing green and Dexcool together is an absolute no-no. If you swap it over flush with system thoroughly first.


http://i11.photobucket.com/albums/a161/black95jimmy/Water Pump Install/NewWaterPumpInsatll007.jpg


Fred

 

[Gary Fowler]

Water pump gaskets are most likely the cause of your loss, very easy job and quite common. It can be done in the yard. Use a mirror and a bright light to check for weepage where the pump meets the front of the block. Iron engine blocks (not aluminum) are more prone to leaking.
As I do maintenance on my equipment I convert them all over to Dexcool, it lasts much longer than the old green stuff. Mixing green and Dexcool together is an absolute no-no. If you swap it over flush with system thoroughly first.


http://i11.photobucket.com/albums/a161/black95jimmy/Water Pump Install/NewWaterPumpInsatll007.jpg


Fred

What about the claim on the Prestone bottle that says it is compatible with ALL COLORS of anti-freeze. That is the reason I bought it, as Prestone has always been associated with excellent product and if it is compatible, I wouldn't have to worry so much about getting all the DEXCOOL out. There is always some left even if you flush with clear water for 1/2 an hour, it still has some greenish tint to the water.

 

[The Fred]

What about the claim on the Prestone bottle that says it is compatible with ALL COLORS of anti-freeze. That is the reason I bought it, as Prestone has always been associated with excellent product and if it is compatible, I wouldn't have to worry so much about getting all the DEXCOOL out. There is always some left even if you flush with clear water for 1/2 an hour, it still has some greenish tint to the water.

I'm no coolant expert by any stretch but I know what works for me after being in the auto biz most of my life. Green is gone with a few exceptions. I notice Kubota still uses it but almost all of the OEM vehicle makers no longer use the green stuff. Subaru stopped in 2008 because federal government allows no maintenance until 100,000 miles depending on emissions code. The green must be replaced every 2 years or 30k miles. We had plenty of Dexcool issues in 96 and 97 vehicles. Heater cores plugged and blocks got contaminated with crud like you couldn't believe.

These days I see Dex-cool cars with 150,000 miles and zero issues, engine tear downs reveal clean clean passages with no crud. Another great coolant is BMW blue OEM anti-freeze. I can testify to seeing many with 10 years 200,000 miles and never a flush or refill. The stuff works great.

Here's a VW that some dumb bugger added green anti-freeze when the car was quite young, this engine had 70,000 miles and was a 2003 model year. The bed plate rotted through, look at the corrosion and the hole in the aluminum plate.

Fred