Green coolant

**Too Fast** · 10-15-2009, 02:16 AM

Originally Posted by tep98ws6

i've never used dexcool in any car, normally just stick with green but i googled and this is what i found : http://www.consumeraffairs.com/news0...m_dexcool.html

That article is over 3 years old, and it disputes itself! In one part they quote some mechanics that say not to use it, then at the end they quote other mechanics who say use it if that's what GM specifies.

It is LACK OF MAINTENENCE that causes issues, everybody.

**TA98** · 10-15-2009, 11:07 AM

Originally Posted by Too Fast

It is LACK OF MAINTENENCE that causes issues, everybody.

Definitly if you take care of it and do what youre supposed to you wont have problems

**tep98ws6** · 10-15-2009, 11:16 AM

i just googled it. i have no stance on what it is or isn't. i use green, always have. i was just googling it for the OP

**TA98** · 10-15-2009, 11:29 AM

I used green cuz i have a ton of it in my garage and i didnt feel the need to spend more money on coolant

**tep98ws6** · 10-15-2009, 11:30 AM

Originally Posted by T/A98

I used green cuz i have a ton of it in my garage and i didnt feel the need to spend more money on coolant

exactly.

**KMdef9** · 10-15-2009, 12:15 PM

I know 4 people who have blown headgaskets and were told it was b/c of dexcool. 3 of the 4 work for GM, are orignal owners, swapped it all to green, and haven't had a problem since. That's part of the reason why I changed it in mine, but I was like others, I was doing a coolant flush and had 2 gallons of good 'ol prestone sitting in the garage, so that's what's in it.

If your going to flush it, I would put the green stuff in because (these are points no one can argue) the green stuff is cheaper and easier to find.

No one has proven that dexcool does damage, otherwise no one on this site would use it. All preference.

**Cutlass** · 10-15-2009, 04:47 PM

Originally Posted by KMdef9

I know 4 people who have blown headgaskets and were told it was b/c of dexcool.

Most likely they were misinformed. What cars/engines were they?

**0rion** · 10-15-2009, 04:53 PM

Originally Posted by KMdef9

I know 4 people who have blown headgaskets and were told it was b/c of dexcool.

I agree with Cutlass. I'm not saying they weren't told that but whoever told them that was wrong. Whenever you get something different that comes along there's always going to be a large amount of people that don't trust it and urban legends form. I'm guilty of the same thing when it comes to the mileage manufacturers/oil companies suggest between oil changes these days.

**pajeff02** · 10-15-2009, 05:04 PM

There are now companies like Prestone, Havoline and Shell that all manufacture "GM Approved DexCool". Has anyone complained about their products? I agree that when it first came out there were issues -- that was clear from all the reading I did on this topic. Plus, lack of proper maintenance will eventually kill any cooling system no matter what is in it.

I am wondering if the problem may be oil seepage into the system as oil runs at a higher pressure than the coolant. A little bit of a leak in a head gasket or an older style intake manifold could result in infiltration. It seems like anything mixed with Dexcool is a bad thing, does this hold true with oil too?

**Cutlass** · 10-15-2009, 05:27 PM

Originally Posted by pajeff02

I am wondering if the problem may be oil seepage into the system as oil runs at a higher pressure than the coolant. A little bit of a leak in a head gasket or an older style intake manifold could result in infiltration. It seems like anything mixed with Dexcool is a bad thing, does this hold true with oil too?

From what I've seen, I'd say no, probably not. The only headgaskets that could leak pressurized oil into the coolant are OHC engines and GM doesn't have a lot of them. Lets see, off the top of my head I can name, the Quad 4, Ecotec, Cadillac Northstar and its cousin the Aurora Northstar, the Baby Northstar 3.5 DOHC V6, and the I5s and I6s in then T/Blazers and Colorados. And none them have any kind of oil/coolant mixture problems as far as I know.

Most people who hate on Dexcool own a 3100/3400 V6 and their famous intake gasket leak. Plan and simple, its a crap gasket and has been updated several times.
Next in line is the 3800 V6 with the melted plastic intake leaking coolant into the engine. They melt because they run exhaust through it to the EGR valve. Dumb idea.
Next would be the Vortec 4.3 V6 and Vortec 5.7 V8 and leaking intake gaskets. Same crap gasket as the 3400 and generally lack of coolant maintainance.

**pajeff02** · 10-15-2009, 05:52 PM

Originally Posted by Cutlass

From what I've seen, I'd say no, probably not. The only headgaskets that could leak pressurized oil into the coolant are OHC engines and GM doesn't have a lot of them. Lets see, off the top of my head I can name, the Quad 4, Ecotec, Cadillac Northstar and its cousin the Aurora Northstar, the Baby Northstar 3.5 DOHC V6, and the I5s and I6s in then T/Blazers and Colorados. And none them have any kind of oil/coolant mixture problems as far as I know.

Most people who hate on Dexcool own a 3100/3400 V6 and their famous intake gasket leak. Plan and simple, its a crap gasket and has been updated several times.
Next in line is the 3800 V6 with the melted plastic intake leaking coolant into the engine. They melt because they run exhaust through it to the EGR valve. Dumb idea.
Next would be the Vortec 4.3 V6 and Vortec 5.7 V8 and leaking intake gaskets. Same crap gasket as the 3400 and generally lack of coolant maintainance.

Had a few of those engines in past vehicles. Thank goodness no issues. Would you have any concerns with the name brand "GM Approved DexCool"? Believe it or not, our local GM dealership did not have any DexCool when I serviced our system in the spring and did not want to order any as they have to get it in bulk. I had to go with the Prestone DexCool, if I remember right.

**Cutlass** · 10-15-2009, 06:09 PM

Originally Posted by pajeff02

Had a few of those engines in past vehicles. Thank goodness no issues. Would you have any concerns with the name brand "GM Approved DexCool"? Believe it or not, our local GM dealership did not have any DexCool when I serviced our system in the spring and did not want to order any as they have to get it in bulk. I had to go with the Prestone DexCool, if I remember right.

No problems with it. I've used it. its probably the exact same stuff made at the exact same place with a different label on it.

**KMdef9** · 10-15-2009, 06:15 PM

Originally Posted by Cutlass

Most likely they were misinformed. What cars/engines were they?

That's what I meant, no one really knows what dexcool "causes." '98 chevy venture, '00 venture, grand am and the other was a blazer, I can't remember what year the grand am or blazer were. I think the ventures were a 3.8? Same as the gt grand am? I really don't know.

Originally Posted by 0rion

I agree with Cutlass. I'm not saying they weren't told that but whoever told them that was wrong. Whenever you get something different that comes along there's always going to be a large amount of people that don't trust it and urban legends form. I'm guilty of the same thing when it comes to the mileage manufacturers/oil companies suggest between oil changes these days.

The urban legend is probably how the "mechanics" came up with "diagnosis".

I have no proof, and I dont think anyone else does either, to prove anything against dexcool. If I had dexcool in my garage that day when I flushed it, dexcool would still be in my car.

**Cutlass** · 10-15-2009, 06:26 PM

The 2 ventures and the Grand Am probably all had the 3400 v6 and I've seen a few external headgasket coolant leaks, but never a blown head gasket, so thats probably what they had. 4.3 Vortec V6 in the Blazer is pretty uncommon for a head gasket problem(internal or external). I've never seen or heard of one.

**0rion** · 10-15-2009, 06:31 PM

Originally Posted by Cutlass

The 2 ventures and the Grand Am probably all had the 3400 v6 and I've seen a few external headgasket coolant leaks, but never a blown head gasket, so thats probably what they had. 4.3 Vortec V6 in the Blazer is pretty uncommon for a head gasket problem(internal or external). I've never seen or heard of one.

that blazer probably was an intake gasket leak. Those 4.3's like to blow coolant out of the front of the intake. I replaced mine a few years ago. Pain in the ass job. The gasket was easy....removing all the shit to get to it was a pain in the ass.

**Wesman** · 10-15-2009, 07:10 PM

I've never had a problem with Dexcool. My issues were limited to replacing the intake gaskets on my L67 3800 Series II S/C, because as Cutlass mentioned, the gaskets were poorly designed from the factory and end up melting and sagging down into the valley. With a set of the new style GM Aluminum intake gaskets, I was on my way.

As for switching to the green coolant, there is no point. It doesn't offer any advantages over Dexcool, and if you don't get all the Dexcool out, you're going to have much bigger problem when the two formulas mix.

For those that want to use something other than Dexcool, just get this:

Thats the Prestone version, but other manufacturers make it as well. Its a light green coolant, it mixes with all colors and types, its compatible with all metals, and it has a service life of 5/150,000 (thats the maximum, not always adviseable though). All you would have to do is drain your old antifreeze out and refill it with the Prestone, no need to completely flush the system.

**FORD RECOVERY EXPERT** · 10-15-2009, 08:39 PM

Just don't mix orange with green and you'll be fine.

**Too Fast** · 10-16-2009, 02:06 AM

Originally Posted by Cutlass

From what I've seen, I'd say no, probably not. The only headgaskets that could leak pressurized oil into the coolant are OHC engines and GM doesn't have a lot of them. Lets see, off the top of my head I can name, the Quad 4, Ecotec, Cadillac Northstar and its cousin the Aurora Northstar, the Baby Northstar 3.5 DOHC V6, and the I5s and I6s in then T/Blazers and Colorados. And none them have any kind of oil/coolant mixture problems as far as I know.

Most people who hate on Dexcool own a 3100/3400 V6 and their famous intake gasket leak. Plan and simple, its a crap gasket and has been updated several times.
Next in line is the 3800 V6 with the melted plastic intake leaking coolant into the engine. They melt because they run exhaust through it to the EGR valve. Dumb idea.
Next would be the Vortec 4.3 V6 and Vortec 5.7 V8 and leaking intake gaskets. Same crap gasket as the 3400 and generally lack of coolant maintainance.

Yes yes and yes. I've fixed these vehicles in the past, and agree with all your comments. You forgot to mention the sludge in that forms in the heater cores/intake on the 4.3 S-10s. This only happens, I've found, from when the owner doesn't make sure the coolant is always full.

Are you old enough to remember all those leaking intakes on the 307 Olds engine, Cutlass? I've replaced many of those, sometimes I bring this up when people say it was the Dexcool that ate the intake gaskets on my _______. I tell them those 307s never ran Dexcool, so how did those gaskets leak? Poor design on the OE gasket. I've never had an intake leak again on any of the engines I replaced them on, and always used the correct coolant.

**pajeff02** · 10-16-2009, 03:52 AM

Originally Posted by Wesman

I've never had a problem with Dexcool. My issues were limited to replacing the intake gaskets on my L67 3800 Series II S/C, because as Cutlass mentioned, the gaskets were poorly designed from the factory and end up melting and sagging down into the valley. With a set of the new style GM Aluminum intake gaskets, I was on my way.

As for switching to the green coolant, there is no point. It doesn't offer any advantages over Dexcool, and if you don't get all the Dexcool out, you're going to have much bigger problem when the two formulas mix.

For those that want to use something other than Dexcool, just get this:

Thats the Prestone version, but other manufacturers make it as well. Its a light green coolant, it mixes with all colors and types, its compatible with all metals, and it has a service life of 5/150,000 (thats the maximum, not always adviseable though). All you would have to do is drain your old antifreeze out and refill it with the Prestone, no need to completely flush the system.

I'm sure you noticed, but the price of the pre-mix 50/50 is outrageous. I can't believe people buy it when you can pick up a gallon of distilled water for less than $1.

**Cutlass** · 10-16-2009, 03:54 AM

Originally Posted by Too Fast

Yes yes and yes. I've fixed these vehicles in the past, and agree with all your comments. You forgot to mention the sludge in that forms in the heater cores/intake on the 4.3 S-10s. This only happens, I've found, from when the owner doesn't make sure the coolant is always full.

^^^^Yep exactly

Originally Posted by Too Fast

Are you old enough to remember all those leaking intakes on the 307 Olds engine, Cutlass? I've replaced many of those, sometimes I bring this up when people say it was the Dexcool that ate the intake gaskets on my _______. I tell them those 307s never ran Dexcool, so how did those gaskets leak? Poor design on the OE gasket. I've never had an intake leak again on any of the engines I replaced them on, and always used the correct coolant.

Nope but I've heard many many stories from the older guys at work(former Olds dealership) and many stories at my old favorite board Oldspower.com