DexCool fix?

**rschap1** · 12-21-2009, 02:14 AM

Saw a few gasket trouble threads and other threads here, but wondering what the most to date fix really is...

Flushed the radiator on the wife's Grand Prix (2000 with non-SC 3800)last winter. This year she says not getting hot. I thought coolant level (oh no possible gaskets) or thermostat. So I take a look. Level looks good, but when I pull the cap, small obs of "jelly". I did replace the stat with a lil' lower temp unit 180 instead of stock 195. She says it acts the same. I would have suspected OVER heating when gelling of this crap AntiFreeze happens, not under temp. BUT...
what's the best fix for this $hit?
I know that there were lawsuits and settlements, but doubt there's any GM Ca$h for me with a 2000 and over 100,000 miles.
Is it advised to flush and use green now?
Any "acids" or cleaners that help get rid of the gunk?
Will be calling the dealer where we got this new just to see what they advise, but I am always a skeptic. And would like any tips or tricks available too.
THANKS in advance!!

Totally unrelated (I hope...) but since I am here...
Sounds like she also needs a MAF sensor for this thing. Best place / price for one?? New only? ACDelco only? Remans from NAPA or Autozone work? Used worth a shot? Appreciate this also!! THANKS AGAIN!!

**Too Fast** · 12-21-2009, 02:28 AM

No problems with Dexcool if you keep it full. As for your no heat, are you sure you have no air in the system after your t-stat replacement? Also, I advise a 195 t-stat, no need for a 185, especially in winter! You may need to backflush your heater core for the no-heat, or it could be something like a blend door issue. A co-worker just last week had a defective new thermostat, drove him crazy, but it was an overheating issue. They can be defective opening too soon, another thought.

Also, stay away from A-Z electronics, my experience tells me they have a higher than average failure rate. I'd get a NAPA, dealer, or similar.

**rschap1** · 12-21-2009, 02:34 AM

Thanks!! I do bleed off all the air when changing stats (actually more proficient at this than I'd like to be)changed them quite a few times trying to keep the wife happy. Coolant temp is actually low. Not just an interior heat issue. Gauge, thermometer in the radiator verify this. May drop the 195 back in too, I just wanted to ensure that the one in place wasn't open when it wasn't supposed to be and knew when summer comes she'll be telling me the car runs too hot. So I was trying to plan ahead rather than doing this again in a few (long---too long) months. (I hate winter in Michigan)

THANKS for the help!!

**0rion** · 12-21-2009, 05:44 AM

if you have blobs in the coolant then it's contaminated. Any leaks at the moment? Dexcool is fine as long as it's clean but once it gets contaminated you need to flush it. Sounds to me like the heater core is probably plugged up with the "blobs". You can either unhook the lines to the heater core and try to back flush it or take it somewhere and let them power flush your system and put new coolant in which is what I would do most likely.

**DIRTY JERZY** · 12-21-2009, 06:47 AM

+1 on that

**OneSlowL36** · 12-21-2009, 07:19 AM

Originally Posted by 0rion

Sounds to me like the heater core is probably plugged up with the "blobs". You can either unhook the lines to the heater core and try to back flush it or take it somewhere and let them power flush your system and put new coolant in which is what I would do most likely.

I go through this every 2 years with my Grand Prix. Very common problem.

**0rion** · 12-21-2009, 08:15 AM

Originally Posted by OneSlowL36

I go through this every 2 years with my Grand Prix. Very common problem.

do you have any gaskets leaking? It's pretty common that once you get any kind of leak the coolant goes to shit shortly there after. My 4.3 is the same way....they just leak and when they do the dexcool takes a shit. I used to backflush mine every year then I finally got around to replacing the lower intake gasket that was leaking and changed the heater core over the summer. It'll run you out of the truck now.

**rschap1** · 12-21-2009, 10:32 AM

I didn't think (was hoping) that I had any gasket troubles. Didn't seem to be losing any coolant or oil. I can see where that scenario would give the result I am seeing. I just hate to admit it. I will try cleaning things out and see if it does it again. APPRECIATE the help!! I did just call the dealer. They say they are still filling cars up with the "pink" stuff. I asked and they said, "yes. the red DexCool". I was surprised. I thought this was an obsolete product now with all the troubles GM saw.

**Orcus79** · 12-21-2009, 04:18 PM

The trouble was not with GM it was the unknown do it your selfers and lazy shops that were mixing the Dexcool with the green stuff. Interestingly enough, all the auto makers use an extended life anti-freeze and the green stuff is now becoming obsolete.

**rschap1** · 12-22-2009, 02:45 AM

My intent wasn't just to hammer GM, and I don't think I did. BUT GM is the only manufacturer I know that has had to pay out settlements to any owners. Regardless of what drove that, I was just wondering what he most up to date and best fix/cure was. While I do maintain this vehicle myself for the most part, if I wasn't totally sure how to repair something, I'd seek help or the dealer. With my wife being the ORIGINAL owner, I know everything that has ever been done to this car. Mostly by me personally. With that, it has never had green stuff mixed, run low on coolant, or had anything besides best of care and preventative service. IF it is a gasket issue, I know GM has recently updated it's intake gasket replacements to aluminum from plastic/silicone since it has been realized that the originals suffer from DexCool. So either way, a properly maintained (since new) motor has gelled up coolant. The system was flushed last year clean and new 50/50 DexCool and water installed. This car is a 2000 with 130k miles. So with the last flush being the third time (after checking wife's records)never has the duration or mileage limits been approached on his product. 50,000;90,000 and120,000 miles each had new antifreeze. To me, I have a hard time not pointing to either the antifreeze product or combo of mismatched antifreeze gasket material pairing. AGAIN not trying to slander or pick on GM, because this has been a fairly good vehicle for us, and what I see as less than major issue after 130,000 miles and ten years is not unexpected. But realize there is something that could have been better here too. Maybe original gaskets should have been different, maybe DexCool tested more...hind site is always 20/20, ya know. Easy for me to say that now. Also my other vehicles have run more miles and longer with the good old green stuff, so why added expense for less/worse performance from a coolant product?

Most importantly!!! I do want to say THANKS for everyone's input, thoughts, and HELP!!! I come here and get great advice and tips and really appreciate it. Just really wanted to clarify that atleast in this example, proper procedures were followed with poor results. I really am not sure of the extent of this "gelling" yet either. What I have seen is the radiator cap, radiator filler neck, and some in the overflow bottle. Maybe I'll get lucky and that is the worst of it (RARELY am I lucky though). It has never lost coolant or oil either, so...

BUT THANKS EVERYONE!!!!!!!!

**Too Fast** · 12-22-2009, 03:51 AM

It's been gasket issues with GM, not the coolant. GM has a history of intake gasket leaks, then they update the gasket design. I can't tell you how many intake gaskets I replaced on the Olds 307 V8s that were made in the 80s. Guess what? This was before Dexcool! And I've desludged many different types of heater cores, from many different makes of cars. Sometimes the backflushing won't get it all out and the core needs to be replaced.

You said on post number 3 that everything is reading low, gauge included. That sure looks like a bad t-stat to me, even from 400 miles away.

**rschap1** · 12-22-2009, 04:03 AM

Replaced the stat. A new 180 first. Then yesterday another new 195 just to be sure. It is in the low teens as I go through this too. Middle of summer, the wife says this car is overheating when it gets over 200 degrees, and now its too cold. SO...what do I do, gotta try and keep her happy and investigate. Thats what I am doing. Trying to find out all I can. Didn't mean to bad mouth DexCool or GMs gaskets either. I had just heard so much about DexCool, problems with it, and wondered if there was a newer bigger better fix. I think I need to dig a little deeper myself rather than just hearing "it doesn't get hot as it should". Over the holidays I will probably get to drive it myself some and see. WHICH BTW, "MERRY CHRISTMAS and HAPPY HOLIDAYS to everyone here". Thanks again!!!!

**Too Fast** · 12-22-2009, 04:07 AM

Just sounds like you need to educate your wife, regarding the summer operational temp of todays cars. 200-225 is exactly where a mass produced engine of today operates. So, this car should have a 195* t-stat, year 'round. And yes, keep digging on the too cool issue. I love to "educate" my wife, LOL!

**0rion** · 12-22-2009, 04:24 AM

just a thought but if your coolant is sludged up then there's a real good chance the heater core is too and that's why her heat isn't getting as warm as it should. I went through this on my truck. It would get warm but never get real hot. It's a vicious cycle really. Something is the root cause of that coolant getting messed up and that's setting the wheels in motion for everything else. Even when I backflushed my heater core it still would never get hot....just above warm. I replaced it over the summer and now you can poach eggs over the defrost vent.

Get your coolant issue figured out before getting into the heater issue because the coolant is at the root of that. I bet if you dig around you're going to find a leaking gasket and most likely it'll be an intake gasket. Feel all the way around that intake and see if you can find the leak. Have a good x-mas and try not to spend all of it working on the car.

**rschap1** · 12-29-2009, 08:55 AM

Originally Posted by Too Fast

You said on post number 3 that everything is reading low, gauge included. That sure looks like a bad t-stat to me, even from 400 miles away.

I did another 195 stat into it and it seems to behave as the wife wants it to, or as she thinks it should. I drove it a little over the holidays and saw nothing out of the ordinary. I don't doubt that there may be some sludge in it and will plan on a good flush including a cleaner (prestone makes on, I take it?) and debating on whether to "go green" afterwards. But it does get as warm as she thinks it used to inside, and I can't imagine much more heat. So I am not thinking the core is too awful bad. Thinking my 180 stat just wasn't getting it when it is so cold here, and the first 195 replacment was bad. New stat seems to be the fix I (she) was after.
THANKS again to everyone for their help and ideas!!
Enjoy the New Year!!!!

**Too Fast** · 12-29-2009, 02:04 PM

^^^Great. Gotta keep the wifey happy!

**Smittro** · 12-29-2009, 06:20 PM

Lots of folks say Dexcool is fine as long as you don't let "air" get to it.. Well that's great, but what about the stuff in your rez? It is always exposed to "air" unless your filling it to the rim lol.. IMHO drain the crap out of your cooling system, flush it and replace with the so called obsolete good old green stuff. I did it a while back in my 01 3800II and never looked back....

**The Guz** · 12-29-2009, 10:00 PM

Check the LIM and UIM for any leaks. The gaskets are notorious for failing on the 3800. I replaced the gaskets on my grand prix at 77K miles. I also needed a new water pump which I changed at the same time I did the gaskets. If you see no leaks then try a good flush. I use the factory T-stat on mine. There is no harm in using the 180. I used the 180 for a short time until it failed. I then replaced it with the stock 195 t-stat.

**Too Fast** · 12-30-2009, 03:20 AM

Originally Posted by Smittro

Lots of folks say Dexcool is fine as long as you don't let "air" get to it.. Well that's great, but what about the stuff in your rez? It is always exposed to "air" unless your filling it to the rim lol.. IMHO drain the crap out of your cooling system, flush it and replace with the so called obsolete good old green stuff. I did it a while back in my 01 3800II and never looked back....

"Air" pocket(s) in the cooling system in the engine, radiator or any part under pressure, not air contact in the resevior. The advantage to Dexcool or other long life coolant is that: Long life, 3-5 years before flushing needed, as opposed to 2 years recommended for the green stuff.

Antifreeze itself doesn't wear out, it's the additives that do.

**Smittro** · 12-30-2009, 03:33 AM

Originally Posted by Too Fast

"Air" pocket(s) in the cooling system in the engine, radiator or any part under pressure, not air contact in the resevior. The advantage to Dexcool or other long life coolant is that: Long life, 3-5 years before flushing needed, as opposed to 2 years recommended for the green stuff.

Antifreeze itself doesn't wear out, it's the additives that do.

Yeah I know about cooling systems there bud. That, is not what I'm talking about. Some folks have said that if air is left in contact with dexcool if will cause things to corrode or gain acidity. Hence the comment about air touching the coolant in the rez. IMHO coolant should be flushed every 2 years anyway.. I don't see a problem as per ruitine servicing. Coolant is cheap and should be replaced aften (evry 2 yrs) in my book..