Man, after reading that info, I'd give your name to one of those lawyers. Sounds like you may have that problem, which is news to me.

I have been hesistant to post anything about AMSOILs anti-freeze because I haven't taken the time to research the GM requirement to use DexCool anti-freeze. After reading the above links, I'm going to have to check it out.

Guess I've been lucky that I have had to change my radiator fluid out routinely. My wife's Trailblazer is a year old. Guess I'll be flushing out her system soon...

For those outside warranty, or who don't care to use DexCool after reading the above, the AMSOIL anti-freeze info:
AMSOIL Antifreeze combines the benefits of biodegradability, low toxicity and all-climate protection. AMSOIL Propylene Glycol Antifreeze and Engine Coolant is safer for kids and pets than ethylene glycol coolants, which are sweet tasting and extremely toxic. Product Code: ANF
Recommended for Applications Requiring the Following Specifications:
Automotive and light Duty Service (ASTM D-5216 & ASTM D-2570)
Heavy Duty Service (ASTM D-6211 & TMC RP330)

 

Hello,

I've never seen this before...maybe someone has!

I have replaced the thermostat in my 1995 coupe with an LT1, 4 times now in the last 6 months. They all have stuck in the closed position casing the obvious overheating. Each time I replaced one, I followed the "burping" proceedures and intitially all was well. If I let the car sit for a week or two, sure enough, the thermostat will stick and excessive tempuratures happen within 5 to 10 minutes of starting the car. I have tried different brands, I even spent $38 for a GM brand and it stuck closed as well. Recently, I had the transmission replaced by a qualified garage who I trust. The car had been unstarted for about 3 weeks while the transmission was built and shipped to this garage. On the test drive for the transmission, the thermostat stuck shut and a proper test was not conducted. The tech called me and told me what had happened and recommended that the thermostat be replaced. I told them to go ahead, maybe they know a better way to purge the cooling system. I picked the car up and drove it home, checked out fine. The next day I started it up and the new (4th) thermostat is stuck shut. I mean the temp gauge is almost pegged and the radiator is stone cold, the heater is blowing cold air.....can anyone offer some advice?

Please help! Thanks!

 

Well,, this is the C5 Tech section BUT,, I have a suggestion. Remove the thermostat and submerge it in boiling water and see if it OPENS. If all the ones you have properly open at the correct water temp, you have other cooling system issues. You could have a partially clogged radiator. They clog from built up scale.

You can have debris in or between the AC condenser and the radiator, preventing proper air flow.

Make sure that your fan is working. properly and coming on at the right times and is moving air.

What is the concentration or coolant to water. Make sure it isn't over 60% coolant.

Is the actual engine over heatingand not moving water. Make sure that the coolant temp sensor isnt defective.

Is your cooling system actually building up the correct pressure?

I think Ive hit all the things to check

Even if you move or change the location of your forum question, please PM me what you find as a solution. I use to have an 85 coupe and I'm interested

 

It would probably help if you started a new thread with YOUR specific problem.

The Forum thread that you linked on to is over 6 years old!

 

Thanks for the replies...I will start a new thread with this problem....

 

....in the C4 Tech section.....

 

FWIW, I have a '96 Z-28, as well as a C-5, so I'm active in both forums. I replaced the t'stat in the Z-28 once, I think, just as a maintenance thing, several years ago, when I replaced the radiator/heater hoses. However, neither the OE t'stat, nor the replacement ever gave me any issues. "Burping" an LT1/4 can be tricky and time consuming, however....