96 Chevy Blazer and Solidified coolant

dac12957

My 96 Chevy Blazer showed my temp in the red zone several times. When I took it to my mechanic he opened the radiator which showed the coolant had solidified. (GM had posted a service bulletin a while ago) Radiator and thermostat replaced. Same problem several weeks later but dealership was able to flush and replace thermostat. Now six months later and you guessed it...once again..Extended warranty will not help because it involves fluids..GM states I should have had coolant flushed at 40,000 even though it states 100,000 in book and on the radiator itself.. In other words,,tough...Anyone else having this problem...My dealer and my mechanic both agree the engine is probably now involved and will need to be stripped down and repaired or replaced...AT MY COST....any suggestions...

Mr_Shiftright

Strange story! Has this engine been pressure tested or leakdown tested for a bad head gasket? Honestly, coolant can't solidify without a contaminant (oil in this case), seems to me, unless I am missing something very unusual here. Is this an automatic? Perhaps the auto trans fluid has leaked from the lower radiator tank to the upper?

jjocjjoc

I've some similar experience with my 1996. First off a dealer actually alerted me to the red crud when I was in for another service and they cleaned up the radiator and flushed the system at no charge. They didn't document the work, but another dealership told the process should be at least 4-5 hours long and changing two thermostats. My temp gauge never got to the Red zone, but it got very close a few times. Took it in twice thinking it was running too hot and both times (two different dealers) dealers mentioned that it was just a little low on coolant and they couldn't duplicate the hot stage. Last version the service manager mentioned that 220.0 temp was normal (mid range is 210 on gauge) for my Blazer and that the gauge was showing 15 degrees hotter than actual temperture taken by shop. Thus, he deduced a big part of the problem was the gauge in the cab is inaccurate or reading hotter than the actual temp. Monitoring the coolant level does seem to help as I seem to lose a little over time. A this seems a little 'hokey' but, who knows....

joe3891

This is the infamous red sludge in the cooling system,GM is well aware of the condition.
GM has sent a 14 min video to all their dealers on how to maintain a dex-cool system,one thing they stress is the coolant in radiator is to be full at all times or it will rust & sludge.I really don't how much I should believe about the condition but I have 2 dex-cool vehicles I am keeping a close eye on.One a 99 & 00.

I am open for any more information on the subject.

dac12957

Here I am, two weeks later and the Blazer is back in again. This morning not only did it hit red zone but started smoking. yup, good old GM told the dealer to flush it again and it should work this time....this is now my sixth visit in as many months...Even the service manager and general manager agree the engine block is now involved but GM says no way... "Wait and see if it works..." Dex Cool IS the issue and now my extended warranty won't cover anything to do with the engine......Just for FYI, my coolant is always filled...so GM can .....

spokane

I have the vague impression that GM devised DexCool because of corrosion in the 60-degree V6 engines which was attributed to conventional ethylene-glycol anti-freeze. But did they jump out of the frying pan and into the fire in trying to solve a problem?

Since my information is incomplete, and surely flawed, can anyone put these corrosion/V6-problems/DexCool-sludge stories in proper perspective?

adc100

I have had the infamous intake manifold leak on a '92 Corsica (125K) and a '94 (75K). Now these leaks occurred after I gave the car (s) to my daughter. The '94 has not been fixed yet but I plan on going up the chain of command at GM until I get turned down, at which time I will take it to small claims court. I would appreciate any info and help on the subject. I ultimately will have **all** of the facts about this issue. But for right now I am not very far except to say that it is a known problem (also known to GM). Well see. Thanks.

paladin7

The engine surges on cold starts. I pulled a code for a idle air control valve. I replaced it. The engine still surges on cold starts. It is like the computer is leaning it out too much. It runs fine after a minute. Has anyone heard of this problem? Also, it just began starting a little harder. The engine has to turn over a little longer than it used to. Maybe a fuel pump or fuel delivery problem. I replaced the fuel filter, but that did not fix it.
Thanks

joe3891

Could be the coolant temp sensor,if it shows hot it will run lean cold.It can be checked with a volt ohm meter.

paladin7

RE: engine surge and long cranking time to start.Thanks,joe3891, I tested coolant sensor and it was o.k. Took it to the dealer to scan test. They said the fuel regulator was leaking. This is the cmfi system. I had to replace the whole fuel injector assembly. Also, I noticed that the oil cooler lines just started to leak, so I had the Chev dealer fix everything. I asked if they had any bulletins on the oil lines. No luck. I told them that this is a chronic problem. Fuel injector and gasket is $450. What a rip! The whole bill is $824. It took care of the problem, but we'll see if it last's. Thanks again.

zr2rando

Mine did the same thing, that year model seams to have that problem a lot from what I hear. Mine was leaking at about 110k, not too bad yet but starting...It leaks fuel out while sitting then the manifold has raw fuel in it when you start up and it messes up the mixture until it all burns/evaporates out..

abbygal

So sorry you have experienced the exact same problem we are now facing with our 1995 Blazer of solidified coolan. We have not had any problems with this great little SUV until recently...now this and also air conditioner clutch (click, click, click...on, off, on, off). Our trusted mechanic says replacing radiator may not be the answer as whole engine could have this junk involved. Air conditioning switch (under hood) replaced to no avail. Answer: My mechanic who makes his living fixing problems and keeping older cars running like tops told me to trade our old friend in ....fast!!! ;-( Good luck with yours.

ocelot1

I thought dexcool was orange? Toyota coolant was red. Am I confused?

joe3891

Dex-cool is orange but sometimes turns red from rust.

ngpro

Yes there is a fix for this! The GM dealer should be able to pull this info off his computer. It is a long ( yes 4-5 hrs) process that involves using a prestone cleaning acid, replacing the cap and thermostat and, of course, lots of flushing. The customer's first complaint about this is usually a lack of heat. This is due to the heater core becoming restricted.

We have performed this proceedure perhaps a dozen times with good results every time except once where we had to replace the heater core because it was too plugged.

If it were my vehicle and was out of any and all warranties I would install the old green coolant after I did the flushing proceedure.

Good Luck!

sweetpea7

You have the Dex-Cool sludge problem! I also have a 96 Blazer and after the 4th flush with no lasting improvement, my dealer discovered the head gasket was leaking. When they replaced/resealed the head gasket, the mechanic must have dropped something in the engine because it blew when they started it. I now have a new engine, new readiator, new water pump, etc. All of this and my prior flushes were at GM expense. GM knows about this problem and there is a Technical Service Bulletin out on it. Even though my warranty had expired, they did all the work for free. Hidden warranty for sure. Go armed with the TSB like I did and they may just take care of it.

PS I now have Prestone green coolant in the new engine. No more Dex-Cool for me!