Going to have a coolant flush done and have a few questions:

1. How often should this be done? I live in Florida and probably going to put about 2k miles a year on the car.

2. Should I use Dexcool? I've had some mechanics tell me this stuff kills seals and should use traditional coolant.

3. Any idea what a flush costs at a dealer these days?

Thanks

_________________
2005 GXP in Black
K&N Filter, tinted windows, tinted headlights, RVinyl fog light covers, Autosport cross-drilled and slotted rotors, EBC Red Stuff pads.
2012 Ford F150 FX2 Super Crew (Daily Driver) 5.0 V8.

1. I have read a few times that with the Northstar engine, you should get a coolant flush every 2-3 years to keep everything fresh and lubricated. Plus that will keep any contaminants out of an already fussy cooling system.

2. Not sure on the dexcool. I know that was a huge issue back with earlier N* engines, but I don't think its as big of an issue now. Quite a few members on here have switched from dexcool to the conventional 'green' coolant.

3. When I got mine done, it ran me about $89 before taxes.

Also, if you get it done at a shop, just make sure that they cleaned out and properly connect the hoses they use. If they don't, you'll just be getting contaminants from a previous vehicle that they performed the service on.

_________________
In My Garage:

1995 Camaro Z28 - LT1 w/ 6-speed, Magnaflow Exhaust, Moroso Cold Air Inake, Powerstop drilled/slotted rotors and ceramic pads, Z06 Chrome Wheels, Founders Performance Strut Tower Brace (Work in Progress)
2010 Dodge Ram SLT Big Horn Edition Quad Cab - 5.7L Hemi, 390HP, 4x4, Daily Driver

Past Vehicles:

1989 Acura Legend - 'Tank'
1999 Dodge Dakota Ext. Cab - 'Bulldog'
2004 Bonneville GXP - 'Red Demon' - Already Missed

***Showed up expecting a battle, left with a laugh***

If the vehicle was just going to be in Florida and only driven 2k a year, I would be really tempted to run at most a 20% coolant solution and add a bottle of cooling system lubricant.

Water is a better conductor of heat than AF; however, even with seeing 0 degrees of freezing weather, you want to run some AF for the simple fact that you don't want to freeze up the heater core (due to the AC).

The original Dexcool was notorious for chewing up gaskets. Supposedly the new variation is better, but the name is tainted forever. There are other universal long life coolants out there as well, so that you can still run a long time on it.

My main concern would be the changes in chemistry as it ages- not something the floating ball coolant tester can really tell you.

_________________

Wouldnt he still want to run 50/50 mix? 50/50 mix boils at 265ish and Water with a little anifreeze in it will boil at a bit over 212?

_________________

It's under pressure why would it boil at 212? All the dirt track racers in Mason City run straight water and they don't have a boiling issue. They get a heck of a lot hotter then 212.

_________________
Seth

Bonita 78,000 miles traded on a CTS4

Oh thats right

_________________

It happens to the best of us, I don't know if I personally would run straight distilled water in my own engine. But at sea level under 14 psi water boils at 248 degrees f.

_________________
Seth

Bonita 78,000 miles traded on a CTS4

Car has 80k miles on it. Any kind of risk making a switch now? Knock on wood the car has no leaks of any kind and would like to keep it that way. :-)

_________________
2005 GXP in Black
K&N Filter, tinted windows, tinted headlights, RVinyl fog light covers, Autosport cross-drilled and slotted rotors, EBC Red Stuff pads.
2012 Ford F150 FX2 Super Crew (Daily Driver) 5.0 V8.

Should probably get the dex out now if its still original.

_________________
Seth

Bonita 78,000 miles traded on a CTS4

If you're religious about it and change it regularly, Dex will be fine, your engine is theoretically designed for it. Seems it's a draw between keeping Dex and using Green coolant. Make sure it gets THOROUGHLY flushed if you use green. If you go to a dealer, they will use Dex, I doubt they'd put green in for you, as they follow GM spec...

_________________
Bye Bye:

RIP sandrock

A proper cooling system contains 50-70% Antifreeze/Coolant, regardless of how much you drive it, regardless of how often you flush it. The coolant is there to not only raise the boiling point of the fluid (under pressure in a properly maintained cooling system), but to lubricate the water pump and prevent corrosion in the system as well.

Flushing the system at prescribed intervals is just as, if not more important. I see the effects of dexcool every day at work, and I can tell you for sure that the dex in a properly working cooling system definitely lasts at least 3 years, and is probably ok up to 5 years on its initial fill. Exceeding this interval is definitely a mistake. Dexcool gets much angrier than most coolants where it will do its typical acidic turning to gel thing which essentially destroys a cooling system. When I flushed out my avalanche a couple years ago, it had 4 years and 90k miles on the Dex that was in it. The fluid was getting very dark and dirty and had lost its sweet smell. After flushing it out (with replacement dexcool, and a new OEM temp thermostat) the engine ran cooler constantly, and the system was 100% happy again. No leaks, no fuss. This was especially important on this specific engine (the 5.3 LM3 Vortec) because it's a bimetal engine which causes coolant degradation much quicker.

After initial fill, regardless of the coolant, regardless of the vehicle, the coolant should be changed between 30-50k miles or every 2 years whichever comes first. I personally recommend the thermostat and cap should be changed before 75-100k miles with high quality replacements. Keeping the cooling system under pressure allows the coolant to properly flow in and out of the overflow tank, keeps peak temperatures down, and keeps air from getting into the system.

_________________
John
Now: '15 Toyota Prius III | 134 hp 2ZR-FXE | Silver | 36k
Now: '03 Honda CR-V AWD | Slow 4-Cylinder | Dirt | 180k
Then: '07 Ford Fusion SEL | 221hp Gen I VVT Duratec 3.0 V6 | Tungsten Silver | 150k
Then: '99 Toyota Avalon XL | 200hp 1MZ-FE 3.0 V6 | Diamond White | 189k | Sold: July 2015
Then: '11 Ford Fusion SEL | 240hp Gen II VVT Duratec 3.0 V6 | Ingot Silver | 84k | Totaled: Oct 23 '14 (Rear-Ended)
Then: '96 Buick Park Avenue Ultra | 240hp Series II L67 | Medium Dark Lichen | Bought: JAN 11 @ 135k | Accident: FEB 3 '12 | Crushed: MAR 1 '13 @ 153K
Then: '98 Pontiac Bonneville SSE | 205hp Series II 3800 L36 | Topaz Firemist | Bought: NOV '09 @ 74k | Accident: MAY 28 '10 | Crushed: MAR 15 '11 @ 84k
Then: '93 Pontiac Bonneville SE | 170hp Series I 3800 L27 | Dark Yellow Green | Bought: JULY '07 @ 92k | Sold: JULY '12 @ 118k
Then: '89 Pontiac Bonneville LE | 165hp 3800 LN3 | Medium Garnet Red | Bought: JAN '05 @ 117k | Sold: SEP 30 '07 @ 152k

Is the Prestone version of Dexcool just as good as the high priced stuff from Mr. Goodwrench ? Also, whats the general opinion on Prestone's cooling system treatment/lubricant additive or, the GM sealing tablet when doing a coolant flush and refill ?

1) I do it annually regardless of mileage driven. Heat is just as bad as cold! You also didn't mention how many miles were on the car. You just mentioned how much you put on per year. If it's up to and past the 100k mark (highly doubtful, but I have to throw this in there), I'd definitely be on it at least once a year.

2) The never ending Dexcool debate. I personally would still run it. Regular old green coolant, I think does do a slightly better job than Dexcool in regards to thermal transfer (I.E. removing the heat from your engine, then removing the heat from the coolant in the radiator), but as much as the debate has, that is what the car is designed to run. HOWEVER, if you should decide to ditch Dexcool for whatever else, you HAVE to make sure that the system is COMPLETLY flushed of the Dexcool. Dexcool and other forms Ethylene Glycol (regular green coolant), Chrysler G-05, etc, ARE NOT compatible. Mixing them can cause cooling system issues, which could cause severe damage to the engine. Usually the only way to make sure you get every drop of Dexcool out, is with a machine that physically power flushes it out.

3) Well, figure somewhere around ~$70 - $90 per hour of labor and a good hour to do it. Then add on about 3 - 4 gallons of whatever you want (I forget the exact capacity off the top of my head but it's easier to have more than you need available rather than to run out and need to go get more), to use. You can even get ready mixed 50/50 solutions which is about the only mixes other than say a 60/40 mix I would recomend regardless of climate/where you live, figure about $14/gallon. While in there, be sure to change your hoses (Upper and lower radiator hoses). And it probably wouldn't hurt to do a new serpentine belt. Plus, any cost they may tack on for a machine to power flush, should you go that route.

These things are real easy to do yourself you know.

_________________


Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*

Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
2004 Pontiac GTO: Impulse Blue Metallic/Black/M6: lots 'o mods, 415 RWHP / 405lb/ft RWTQ!
2006 Cadillac STS-V: Light Platinum Metallic/Light Gray/A6 - Spectre CAI, Magnaflow exhaust, Speed Inc. tune, 412 RWHP / 472lb/ft RWTQ

Daily Drivers:
2019 Chrysler Pacifica Limited: Mommy's new RGC
2015 Chrysler Town & Country Limited Platinum: Kids new RGC
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck

Yes, that or Zerex is usually what I use.

I would highly recommend the pill OR going through a sealing process after you've drained your old coolant out. These cars are notorious for cooling system leaks, namely freeze plugs and a couple other places.

I used some stuff in a can, that after I completely drained the system, I then added the contents of this can, filled back up until full with regular water, let it run and circulate at full temp for 15 - 20 minutes, then completely drained it, and let it sit and cure for 24 hours. After which, I then refilled with Dexcool. Never had another leak again.

_________________


Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*

Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
2004 Pontiac GTO: Impulse Blue Metallic/Black/M6: lots 'o mods, 415 RWHP / 405lb/ft RWTQ!
2006 Cadillac STS-V: Light Platinum Metallic/Light Gray/A6 - Spectre CAI, Magnaflow exhaust, Speed Inc. tune, 412 RWHP / 472lb/ft RWTQ

Daily Drivers:
2019 Chrysler Pacifica Limited: Mommy's new RGC
2015 Chrysler Town & Country Limited Platinum: Kids new RGC
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck

I just remembered a throttle body/manifold related recall on our 2000 SLE during which they popped in an additional GM cooling sys.pellet. Apparently they were added even earlier as a service bulletin fix. I saw some slimy looking goop in the reservoir when I first bought the car at approx 24,000 mi. from the Pontiac dealer where it was sold originally. I was told it was the result of an across the board sealant pellet treatment that all the Bonnevilles got. I've always been worried about all that junk clogging passages up, and doing more harm than good. Does a flush, home or professional, usually remove the old sealant ?

One thing of note--} avoid the quick lube coolant flushes. Most of them are using some eco-friendly machine which basically does a coolant exchange, and the system is not actually flushed of all coolant.

The ideal flush would be to flush water through until the coolant system was 100% water, and then drain it out the best you can, add the straight AF in the correct amount and top off with water

_________________

My exwife had a '96 Lumina when we were dating.

She never had the coolant changed because her dad kept telling her the dex cool lasts 10 years.

Then in 2007 she was driving one day and every single gasket in the cooling system blew.

That's when she learned about the whole thing with corossion and build up.

I need to check the service records I was given and see if it's been done on my car.