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Author Topic:   FYI - 1995 or newer GM towing vehicles

hauptjm posted 02-06-2003 03:41 PM ET (US)
Since, we have discussed towing vehicles here in the past, I thought I would pass this on to anyone with a 1995 or newer GM Truck or SUV. I know we have many GM owners here. Use extreme caution with Dex-Cool antifreeze.
For those unfamiliar with Dex-Cool, it is the GM product (developed by Texaco) that is used in their long-term (100k+ miles) cooling system. Unfortunately, the system doesn't work. Dex-Cool crystallizes when it comes into contact with air and rips up the inside of the cooling system and the heater core. There is a class-action suit being put together as we speak.
It is almost impossible to prevent your cooling system from being "contaminated" with air. The systemic flaws are more prone to the Blazer model, but has been seen in all GMs with Dex-Cool.
I have pulled just four of the service bulletins issued by GM on my model and year, and they are all clear that there is a huge problem. Unfortunately, GM is not offering to fix these beast under warranty (extended) or offering any kind of post-secret warranty. Imagine the exposure GM has with all of the Burbs, Tahoes, Blazers, etc sold in the last 7 or 8 years.
If it goes to far, the heater core has to be replaced. This runs around $1,200 in parts and labor. The dashboard has to come off to reveal the heater core. The other system replacements will include a new water pump and radiator. Total repairs can run around $3,000.00.
I just had mine acid flushed by GM dealer after taking my complaint to the regional GM district manager. I am under warranty and it still cost me $600.00.
Some URLs that can help with this and other automobile service issues:\\
http://www.alldata.com/recalls/
http://www.nhtsa.dot.gov/cars/problems/tsb/Index.cfm
http://www.geocities.com/b_gillie/dexcool_problems.html

IndyDave posted 02-06-2003 04:00 PM ET (US)
SO, can't you just drain the radiator/engine, and flush it well, and refill with the "old" stuff?? How many miles until contamination occurs??
Florida15 posted 02-06-2003 04:03 PM ET (US)
The website just mentioned problems with the 4.3 V6. Is that the only engine they've
had problems with ?
T Party posted 02-06-2003 04:11 PM ET (US)
Thanks for the tip! I'm taking my 1999 Tahoe in for its 60,000 service soon (maybe tomorrow) and will be sure to have this problem checked.
BOB KEMMLER JR posted 02-06-2003 04:17 PM ET (US)
I have a 1995 Caprice wagon and it has the old stuff in it,which models have the new stuff?
John O posted 02-06-2003 05:23 PM ET (US)
We are having problems with out 1998 Blazer. the heater core is gurgeling for lack of a better word. We have 98k on the truck. We were looking to buy a new Trailblazer/Envoy and did not plan to replace the heater core. It is a nasty job. I tried to replace one on a 1985 Audi. Had to go through the dash and glove box. Finally quit and had a pro do it. Took about 4 hours. The truck runs great and we may keep as a second tow vehicle as I have a company car.
hauptjm posted 02-06-2003 05:30 PM ET (US)
Apparently, the most occurring models are the V-6 SUVs. According to my source at GM they were using the DEX-Cool first back to '95. That would make sense since there seems to be an incubation period of several years for it to do its damage, assuming the coolant becomes contaminated. My understanding now is that all of the GM models are using it. I can't guarantee that. I am sure that all of the SUVs and higher-end autos are using it after '99 to present.
My first problem showed up just this January at around 62,000 miles. This seems to be the average mileage and age.
hauptjm posted 02-06-2003 05:36 PM ET (US)
Additionally, I am on an alert list that if or when GM owns up to the problem, I'll be notified. GM would then offer some solution to the inherent problem at little or no cost to the owner. This would include cars that have passed their warranty periods and or have been sold to another owner. I would not hold my breath, but you never know what a class action suit can bring.
I will alert everyone if it ever comes.
John O posted 02-06-2003 06:17 PM ET (US)
Very disappointed with GM after reading about the problem that I thought was just ours. We will not buy GM until this is settled. We just had our oil coolong lines repalced for $500.00 PLUS dollars. Sounds related.
jimithing posted 02-07-2003 12:20 PM ET (US)
From what I can garner from the information supplied in the links this does not concerne models 2001 and later. Just to be sure I plan on checking with my dealer.
Whalerdan posted 02-07-2003 12:24 PM ET (US)
My '96 Astro van's heater core is doing the same thing-gurgling. Sounds like I have the same problem. I just replace the radiator and hosed last fall. That heater core will be a b@#ch to change. How do you get in on that class action lawsuit?
Florida15 posted 02-07-2003 12:45 PM ET (US)
I forwarded this thread to a friend of mine and this is the reply I got:
I just called the Chevy dealer and talked to the service dept. manager. He knows me pretty well because of the problems I had with the Siverado and he's been honest with me. He said he recommends a flush and new anti-freeze every 50,000. The problems he's seen with the Dex-cool usually started with another problem. The anti-freeze would be low because of a leak and air would get in the system. That's when the stuff crystalizes and turns into a jell. He said as long as it clean and full you shouldn't have a problem.
hauptjm posted 02-07-2003 02:12 PM ET (US)
Florida15, your guy was fairly accurate in that he was following the company line. In my car there was never a leak. Fluids were kept to spec at regular intervals. In fact, the training tape GM put out for the repairs even states the Blazer needs modification to a breather tube because the factory issue is not long enough to prevent air from entering the system. Bottom line is that the system should be able to handle air being introduced in reasonable circumstances. Since a cars cooling system is not a closed system, air will enter.
By the way, the acid wash flush recommended by GM is a 5-hour process. At $85/hour labor charge at dealers in my area, just the flush is over $400.00. Removing a heater core generally requires removal of the dashboard. Imagine the labor hours to that. Not to mention the cost of parts.
Lastly, and I think most poignant, is that the GM regional told the dealer not to refill with Dex-Cool. I've got good old fashion green antifreeze.
Florida15 posted 02-07-2003 02:37 PM ET (US)
So, it will not hurt the system to go back to the old green stuff ? I thought maybe it was designed just for the Dex-Cool.
Sounds like that may be the way to go.
tbyrne posted 02-07-2003 03:49 PM ET (US)
Whalerdan,
Class action suit!! I thought this was an anti-lawyer board. No one likes lawyers until they feel they have been wronged. . .
And yes, I'm a lawyer - just not an ambulance chaser.
TightPenny posted 02-11-2003 11:32 PM ET (US)
Glad I bought an F-250
whalerron posted 02-11-2003 11:50 PM ET (US)
My friend had this problem with his Chevy Blazer (1995?). The heater core had become completely blocked. He took the Blazer to his mechanic. The mechanic knew of the problem but didn't feel the heater cores all needed to be replaced. The mechanic blew compressed air, in the reverse direction of the coolant flow, through the core and then reverse flushed the core. After that, my friend never had anymore trouble with the heater or any part of the cooling system in that truck.
Swellmonster posted 02-12-2003 07:30 AM ET (US)
I have a 99 hoe with 110K, dexcool.
No problems yet.....
I also gunna look into this issue. :C
hauptjm posted 02-12-2003 11:46 AM ET (US)
tbyrne,
One major difference - no one is looking for punitive damages or cash - just want the manufacturer to repair what is obviously a design flaw. Fix the problem and move on: nothing more.
dfmcintyre posted 02-12-2003 04:17 PM ET (US)
Our family business is a third generation GM dealership. I sent the thread to our business partner (who's also a Whaler owner, btw...) who explained the situation. He got the info from the service manager, and while it makes sense, it could be slightly off.
The problem _could_ effect the 4.3 liter engines. They have not heard or experienced any problems with the larger blocks. And not all 4.3's either.
According to a factory source, the problem may have resulted from long term storage that resulted in internal rust forming. Being cast iron, exposed long term in a wet or damp storage area it makes sense.
And he told me that it's a policy work issue.
Don
Whalerdan posted 02-13-2003 08:00 AM ET (US)
WHAT THE HECK DOES THAT MEAN "Long term storage."? My Astro Van has a 119,000 miles and has never been stored. It makes me sick. In the past 6 months I've put more into this darn thing than it's worth, thinking it would make it last another 2-3 years. The dealer never mentioned any of this stuff, and I know he must have known.
hauptjm posted 02-13-2003 10:36 AM ET (US)
I have to admit I'm flummoxed at the storage argument. I spent a 1/2 hour speaking with the head mechanic at the largest GM dealer in my city and he said unequivocally that it's a flaw in the chemical makeup of Dex-Cool. A flaw in that any coolant material should be able to standup to air. The crystallization of the coolant is what is eating the core, not damp storage. GM's own service bulletins and subsequent training videos sent to the dealers clearly explain this.
Also, the problems have been located in the V-8s, but certainly not with the severity of the 4.3 V-6.
TRAFFICLAWYER posted 02-13-2003 02:47 PM ET (US)
tbyrne:
How right you are, this is one if not the most prolific lawyer bashing site in the boating world. Interesting how technonerds whine lawyer when they need another class action suit that favors the whiners.
rubadub555 posted 02-13-2003 08:46 PM ET (US)
Another lawyer/Whaler fan here to note the shifting wind; it all depends on whose ox is in the ditch. As I recall, one case in which someone was killed by an unguarded prop was the nadir of western society, but when your radiator has a problem, you rush to sign up for the class action? Not to derail what is a useful (non-Whaler) thread, but the shift is laughable.
simonmeridew posted 02-13-2003 09:34 PM ET (US)
rub:
From last month's annotated post, I conclude as follows:
It's ok to put (unguarded) props on outboards... since everyone knows they can maim or kill you.
Would the same logic make me conclude:
Chevy can put defective coolant in their trucks...since everyone knows Chevys are no good anyway?
simonmeridew
Bigshot posted 02-15-2003 12:58 PM ET (US)
Bud owns an 8 bay shop. He says get it out before 50k if possible. Stuff turns to mud and clogs heater cores. If you live in FL...no biggie, just no heat.
dfmcintyre posted 02-17-2003 10:32 AM ET (US)
Shoulda explained further:
The storage rumor has to do with "raw" blocks, i.e., blocks that were stored in a damp area without any head, pan, etc. attached, and that enough rust had formed internally to cause problems at a later time.
Don
flawton posted 02-17-2003 10:45 AM ET (US)
Dexicool is horrible. I have a 97 S-10 pickup with the 4.6l V-6. At 75,000 miles had to have a new radiator core. I now have 85,000 miles and have gone through 4 thermostats. It took less than a year on the new radiator for the dexicool to degrade and the coolant looked like sludge. I had my small town mechanic flush it well and have replaced the deexicool with traditional green coolant. No prblems since then. Just say no to dexicool.
Florida15 posted 02-17-2003 11:55 AM ET (US)
Most every mechanic I talked to said to replace Dex-Cool on a regular basis and you shouldn't have any problems. I asked two mechanics about replacing it with the old green stuff and they both said they wouldn't because it would be hard to get every drop of dex-cool out of your system
and the two don't mix. These were independents, not GM mechanics.
I have a 1999 Z-71 with 63,000 miles on it.
I'm not saying I won't have problems, just have been lucky so far.
hauptjm posted 02-18-2003 11:30 AM ET (US)
Florida15, you are correct about having to rid the entire system of Dex-Cool. The only way is the acid flush that takes 5 hours. After which you are good to go with conventional coolant.
Louie Kokinis posted 03-01-2003 11:16 PM ET (US)
I had my system flushed and refilled with conventional coolant today.
I decided to do this after speaking to a couple of gm mechanics. Both confirmed that Dex-Cool was problematic the 4.3 blocks (but not limited to them), and that if changed every 2 years there shouldn�t be a problem.
I didn�t like the sound of �shouldn�t be a problem� or paying a premium for a long-life coolant that �should� be replaced every 2 years.
Thanks for the heads-up!
Gene in NC posted 03-02-2003 01:30 AM ET (US)
My '94 5.7 Sub has 180k on orig cooling system, trans, engine. Green coolant changed at 24 mos and Quality synthetic lube will take your tow a long way, even pulling horse trailer at which mine has more hours than I'd like. '91 S10 w 4.3 has bad heater core at 125k.
chorescanwait posted 03-02-2003 06:23 PM ET (US)
This is all sinking in now. I used to own a 97 Safari van purchased the 100k warranty it paid for it self 5X over first the water pump @ 42,000 then the main seal at 98,000. Worse than that 3 rear ends in less than a week. Lets top that off by transmission going out at 132,000. And yes I was stupid enough to trade it in on a GMC Sierra 2002. Currently have 33,000 and the Dex-Cool.
UNKAJOEinVA posted 08-15-2008 05:47 PM ET (US)
Hey thanks for the note on the antifreeze coolant crystalizing. I just replaced a corroded freeze in my
95 Chevy astro van. The stuff that came out was red and grity - somewhat goohy. My mechanic thinks someone had used stop leak but no way. I bought the van used and had all coolant and fluids change. It was green back then. I since used the gm approved stuff and now its not green but like I said above. I flushed it several times - seems I can't get rid of the stuff now. While down I replaced the water pump and Tstat. 2 months later a heater hose with metal on it sprang a leak. I just replaced that. Jeeze.
For some reason now I have another issue with the tranny not shifting, the anti-brake light on and the speedometer is dead.......when it rains it poors. Still no solution to the later. tx fer listening. UNKAJOEinVA
Hey If you know whats up with the latter statement I'd appreciate the help. I replace the tranny speed sensor today without and improvement whatsoever. Leave info here or email me you GM dudes (mechanics) that know whats going on.

UNKAJOEinVA posted 08-15-2008 05:56 PM ET (US)
Hey Whalerdan, actually that heater core is not that hard to get to on the Astro. I had 93 and 95's.
UNKAJOEinVA posted 08-15-2008 05:58 PM ET (US)
Hey Whalerdan, actually that heater core is not that hard to get to on the Astro. I had 93 and 95's.

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Author	Topic: FYI - 1995 or newer GM towing vehicles
hauptjm	posted 02-06-2003 03:41 PM ET (US) Since, we have discussed towing vehicles here in the past, I thought I would pass this on to anyone with a 1995 or newer GM Truck or SUV. I know we have many GM owners here. Use extreme caution with Dex-Cool antifreeze. For those unfamiliar with Dex-Cool, it is the GM product (developed by Texaco) that is used in their long-term (100k+ miles) cooling system. Unfortunately, the system doesn't work. Dex-Cool crystallizes when it comes into contact with air and rips up the inside of the cooling system and the heater core. There is a class-action suit being put together as we speak. It is almost impossible to prevent your cooling system from being "contaminated" with air. The systemic flaws are more prone to the Blazer model, but has been seen in all GMs with Dex-Cool. I have pulled just four of the service bulletins issued by GM on my model and year, and they are all clear that there is a huge problem. Unfortunately, GM is not offering to fix these beast under warranty (extended) or offering any kind of post-secret warranty. Imagine the exposure GM has with all of the Burbs, Tahoes, Blazers, etc sold in the last 7 or 8 years. If it goes to far, the heater core has to be replaced. This runs around $1,200 in parts and labor. The dashboard has to come off to reveal the heater core. The other system replacements will include a new water pump and radiator. Total repairs can run around $3,000.00. I just had mine acid flushed by GM dealer after taking my complaint to the regional GM district manager. I am under warranty and it still cost me $600.00. Some URLs that can help with this and other automobile service issues:\\ http://www.alldata.com/recalls/ http://www.nhtsa.dot.gov/cars/problems/tsb/Index.cfm http://www.geocities.com/b_gillie/dexcool_problems.html
IndyDave	posted 02-06-2003 04:00 PM ET (US) SO, can't you just drain the radiator/engine, and flush it well, and refill with the "old" stuff?? How many miles until contamination occurs??
Florida15	posted 02-06-2003 04:03 PM ET (US) The website just mentioned problems with the 4.3 V6. Is that the only engine they've had problems with ?
T Party	posted 02-06-2003 04:11 PM ET (US) Thanks for the tip! I'm taking my 1999 Tahoe in for its 60,000 service soon (maybe tomorrow) and will be sure to have this problem checked.
BOB KEMMLER JR	posted 02-06-2003 04:17 PM ET (US) I have a 1995 Caprice wagon and it has the old stuff in it,which models have the new stuff?
John O	posted 02-06-2003 05:23 PM ET (US) We are having problems with out 1998 Blazer. the heater core is gurgeling for lack of a better word. We have 98k on the truck. We were looking to buy a new Trailblazer/Envoy and did not plan to replace the heater core. It is a nasty job. I tried to replace one on a 1985 Audi. Had to go through the dash and glove box. Finally quit and had a pro do it. Took about 4 hours. The truck runs great and we may keep as a second tow vehicle as I have a company car.
hauptjm	posted 02-06-2003 05:30 PM ET (US) Apparently, the most occurring models are the V-6 SUVs. According to my source at GM they were using the DEX-Cool first back to '95. That would make sense since there seems to be an incubation period of several years for it to do its damage, assuming the coolant becomes contaminated. My understanding now is that all of the GM models are using it. I can't guarantee that. I am sure that all of the SUVs and higher-end autos are using it after '99 to present. My first problem showed up just this January at around 62,000 miles. This seems to be the average mileage and age.
hauptjm	posted 02-06-2003 05:36 PM ET (US) Additionally, I am on an alert list that if or when GM owns up to the problem, I'll be notified. GM would then offer some solution to the inherent problem at little or no cost to the owner. This would include cars that have passed their warranty periods and or have been sold to another owner. I would not hold my breath, but you never know what a class action suit can bring. I will alert everyone if it ever comes.
John O	posted 02-06-2003 06:17 PM ET (US) Very disappointed with GM after reading about the problem that I thought was just ours. We will not buy GM until this is settled. We just had our oil coolong lines repalced for $500.00 PLUS dollars. Sounds related.
jimithing	posted 02-07-2003 12:20 PM ET (US) From what I can garner from the information supplied in the links this does not concerne models 2001 and later. Just to be sure I plan on checking with my dealer.
Whalerdan	posted 02-07-2003 12:24 PM ET (US) My '96 Astro van's heater core is doing the same thing-gurgling. Sounds like I have the same problem. I just replace the radiator and hosed last fall. That heater core will be a b@#ch to change. How do you get in on that class action lawsuit?
Florida15	posted 02-07-2003 12:45 PM ET (US) I forwarded this thread to a friend of mine and this is the reply I got: I just called the Chevy dealer and talked to the service dept. manager. He knows me pretty well because of the problems I had with the Siverado and he's been honest with me. He said he recommends a flush and new anti-freeze every 50,000. The problems he's seen with the Dex-cool usually started with another problem. The anti-freeze would be low because of a leak and air would get in the system. That's when the stuff crystalizes and turns into a jell. He said as long as it clean and full you shouldn't have a problem.
hauptjm	posted 02-07-2003 02:12 PM ET (US) Florida15, your guy was fairly accurate in that he was following the company line. In my car there was never a leak. Fluids were kept to spec at regular intervals. In fact, the training tape GM put out for the repairs even states the Blazer needs modification to a breather tube because the factory issue is not long enough to prevent air from entering the system. Bottom line is that the system should be able to handle air being introduced in reasonable circumstances. Since a cars cooling system is not a closed system, air will enter. By the way, the acid wash flush recommended by GM is a 5-hour process. At $85/hour labor charge at dealers in my area, just the flush is over $400.00. Removing a heater core generally requires removal of the dashboard. Imagine the labor hours to that. Not to mention the cost of parts. Lastly, and I think most poignant, is that the GM regional told the dealer not to refill with Dex-Cool. I've got good old fashion green antifreeze.
Florida15	posted 02-07-2003 02:37 PM ET (US) So, it will not hurt the system to go back to the old green stuff ? I thought maybe it was designed just for the Dex-Cool. Sounds like that may be the way to go.
tbyrne	posted 02-07-2003 03:49 PM ET (US) Whalerdan, Class action suit!! I thought this was an anti-lawyer board. No one likes lawyers until they feel they have been wronged. . . And yes, I'm a lawyer - just not an ambulance chaser.
TightPenny	posted 02-11-2003 11:32 PM ET (US) Glad I bought an F-250
whalerron	posted 02-11-2003 11:50 PM ET (US) My friend had this problem with his Chevy Blazer (1995?). The heater core had become completely blocked. He took the Blazer to his mechanic. The mechanic knew of the problem but didn't feel the heater cores all needed to be replaced. The mechanic blew compressed air, in the reverse direction of the coolant flow, through the core and then reverse flushed the core. After that, my friend never had anymore trouble with the heater or any part of the cooling system in that truck.
Swellmonster	posted 02-12-2003 07:30 AM ET (US) I have a 99 hoe with 110K, dexcool. No problems yet..... I also gunna look into this issue. :C
hauptjm	posted 02-12-2003 11:46 AM ET (US) tbyrne, One major difference - no one is looking for punitive damages or cash - just want the manufacturer to repair what is obviously a design flaw. Fix the problem and move on: nothing more.
dfmcintyre	posted 02-12-2003 04:17 PM ET (US) Our family business is a third generation GM dealership. I sent the thread to our business partner (who's also a Whaler owner, btw...) who explained the situation. He got the info from the service manager, and while it makes sense, it could be slightly off. The problem _could_ effect the 4.3 liter engines. They have not heard or experienced any problems with the larger blocks. And not all 4.3's either. According to a factory source, the problem may have resulted from long term storage that resulted in internal rust forming. Being cast iron, exposed long term in a wet or damp storage area it makes sense. And he told me that it's a policy work issue. Don
Whalerdan	posted 02-13-2003 08:00 AM ET (US) WHAT THE HECK DOES THAT MEAN "Long term storage."? My Astro Van has a 119,000 miles and has never been stored. It makes me sick. In the past 6 months I've put more into this darn thing than it's worth, thinking it would make it last another 2-3 years. The dealer never mentioned any of this stuff, and I know he must have known.
hauptjm	posted 02-13-2003 10:36 AM ET (US) I have to admit I'm flummoxed at the storage argument. I spent a 1/2 hour speaking with the head mechanic at the largest GM dealer in my city and he said unequivocally that it's a flaw in the chemical makeup of Dex-Cool. A flaw in that any coolant material should be able to standup to air. The crystallization of the coolant is what is eating the core, not damp storage. GM's own service bulletins and subsequent training videos sent to the dealers clearly explain this. Also, the problems have been located in the V-8s, but certainly not with the severity of the 4.3 V-6.
TRAFFICLAWYER	posted 02-13-2003 02:47 PM ET (US) tbyrne: How right you are, this is one if not the most prolific lawyer bashing site in the boating world. Interesting how technonerds whine lawyer when they need another class action suit that favors the whiners.
rubadub555	posted 02-13-2003 08:46 PM ET (US) Another lawyer/Whaler fan here to note the shifting wind; it all depends on whose ox is in the ditch. As I recall, one case in which someone was killed by an unguarded prop was the nadir of western society, but when your radiator has a problem, you rush to sign up for the class action? Not to derail what is a useful (non-Whaler) thread, but the shift is laughable.
simonmeridew	posted 02-13-2003 09:34 PM ET (US) rub: From last month's annotated post, I conclude as follows: It's ok to put (unguarded) props on outboards... since everyone knows they can maim or kill you. Would the same logic make me conclude: Chevy can put defective coolant in their trucks...since everyone knows Chevys are no good anyway? simonmeridew
Bigshot	posted 02-15-2003 12:58 PM ET (US) Bud owns an 8 bay shop. He says get it out before 50k if possible. Stuff turns to mud and clogs heater cores. If you live in FL...no biggie, just no heat.
dfmcintyre	posted 02-17-2003 10:32 AM ET (US) Shoulda explained further: The storage rumor has to do with "raw" blocks, i.e., blocks that were stored in a damp area without any head, pan, etc. attached, and that enough rust had formed internally to cause problems at a later time. Don
flawton	posted 02-17-2003 10:45 AM ET (US) Dexicool is horrible. I have a 97 S-10 pickup with the 4.6l V-6. At 75,000 miles had to have a new radiator core. I now have 85,000 miles and have gone through 4 thermostats. It took less than a year on the new radiator for the dexicool to degrade and the coolant looked like sludge. I had my small town mechanic flush it well and have replaced the deexicool with traditional green coolant. No prblems since then. Just say no to dexicool.
Florida15	posted 02-17-2003 11:55 AM ET (US) Most every mechanic I talked to said to replace Dex-Cool on a regular basis and you shouldn't have any problems. I asked two mechanics about replacing it with the old green stuff and they both said they wouldn't because it would be hard to get every drop of dex-cool out of your system and the two don't mix. These were independents, not GM mechanics. I have a 1999 Z-71 with 63,000 miles on it. I'm not saying I won't have problems, just have been lucky so far.
hauptjm	posted 02-18-2003 11:30 AM ET (US) Florida15, you are correct about having to rid the entire system of Dex-Cool. The only way is the acid flush that takes 5 hours. After which you are good to go with conventional coolant.
Louie Kokinis	posted 03-01-2003 11:16 PM ET (US) I had my system flushed and refilled with conventional coolant today. I decided to do this after speaking to a couple of gm mechanics. Both confirmed that Dex-Cool was problematic the 4.3 blocks (but not limited to them), and that if changed every 2 years there shouldn�t be a problem. I didn�t like the sound of �shouldn�t be a problem� or paying a premium for a long-life coolant that �should� be replaced every 2 years. Thanks for the heads-up!
Gene in NC	posted 03-02-2003 01:30 AM ET (US) My '94 5.7 Sub has 180k on orig cooling system, trans, engine. Green coolant changed at 24 mos and Quality synthetic lube will take your tow a long way, even pulling horse trailer at which mine has more hours than I'd like. '91 S10 w 4.3 has bad heater core at 125k.
chorescanwait	posted 03-02-2003 06:23 PM ET (US) This is all sinking in now. I used to own a 97 Safari van purchased the 100k warranty it paid for it self 5X over first the water pump @ 42,000 then the main seal at 98,000. Worse than that 3 rear ends in less than a week. Lets top that off by transmission going out at 132,000. And yes I was stupid enough to trade it in on a GMC Sierra 2002. Currently have 33,000 and the Dex-Cool.
UNKAJOEinVA	posted 08-15-2008 05:47 PM ET (US) Hey thanks for the note on the antifreeze coolant crystalizing. I just replaced a corroded freeze in my 95 Chevy astro van. The stuff that came out was red and grity - somewhat goohy. My mechanic thinks someone had used stop leak but no way. I bought the van used and had all coolant and fluids change. It was green back then. I since used the gm approved stuff and now its not green but like I said above. I flushed it several times - seems I can't get rid of the stuff now. While down I replaced the water pump and Tstat. 2 months later a heater hose with metal on it sprang a leak. I just replaced that. Jeeze. For some reason now I have another issue with the tranny not shifting, the anti-brake light on and the speedometer is dead.......when it rains it poors. Still no solution to the later. tx fer listening. UNKAJOEinVA Hey If you know whats up with the latter statement I'd appreciate the help. I replace the tranny speed sensor today without and improvement whatsoever. Leave info here or email me you GM dudes (mechanics) that know whats going on.
UNKAJOEinVA	posted 08-15-2008 05:56 PM ET (US) Hey Whalerdan, actually that heater core is not that hard to get to on the Astro. I had 93 and 95's.
UNKAJOEinVA	posted 08-15-2008 05:58 PM ET (US) Hey Whalerdan, actually that heater core is not that hard to get to on the Astro. I had 93 and 95's.