At what mileage interval should one change the coolant and do a flush on a 2001 5.2L ??

 

If using regular green anti-freeze, 5-years is the maximum lifespan.

 

man am I glad you're part of this forum!!!! But what happens after 5 years???? Not that I'm not going to get the stuff changed out, mine looks sorta greenish yellow. Thanks

 

Your greenish/yellow antifreeze is most likely a long life (5 year) multi mixable coolant (supposed to be able to be mixed with the old trusted green, orange like GM Dexcool (garbage in my opinion) Mopar reddish orange looking coolant and such.

After 2 years on the traditional green or 5 years on long life coolant the anti rusting/anti corrosion inhibitors break down and can start causing issues in the system.

Some here with the Magnum series engines have found that going longer than 2 years even on LL coolant has caused rust issues to develop.

 

Your coolant never looses the ability to cool the engine, but the anti-rust additives (and the other additives) suffer a serious decrease in efficiency after 3-5 years depending on the quality of the coolant you are using.

 

Go full green coolant at 50% and 50% DISTILLED water. The old trusted green stuff has the best corrosion inhibitor while the LL and EX-L coolants are marginal for corrosion inhibitors. NEVER use the Dex-Cool junk as MAR pointed out.

 

Hi,
I am the tech manager at Prestone coolants. Lots of misinformation here. Your vehicle came from the factory with green colored HOAT coolant. Change interval is 5 years or 100k miles, whatever comes first. It is NOT "old style" green silicated coolant, that type of coolant is old technology and is supposed to be changed every two years. HOAT stands for Hybrid Organic Acid Coolant. The HOA is speaking to the corrosion inhibitiors. Long life HOAT and OAT coolants are superior in every way to the old style green silicated coolants. The info on here is wrong as can be. Dex Cool got a bad rap because of poorly designed cooling systems in the 90's. In fact, in 2011 Chrylser, Ford, GM, BMW, VW and Mercedes are now all using Dex-Cool. Drain your coolant, fill it with water and Prestone (or your favorite brand) super flush, run the truck for 30 minutes with the heater on. Drain and fill with water, run it for 10 minutes and drain again. Change your thermostat and fill with 50/50 mixture of long life coolant and distilled or dionized water. You can get this for a buck a gallon at the grocery store. Your good for another five years. If you need more instructions, jay.buckley@honeywell.com

 

GM cars through at least 2003 had issues with DexCool. GM even had a settlement regarding DexCool. I wont use and I don't recommend it.

That said I do use long life coolants in my repairs and in both my van and 77 Chevy Impala.

 

I never saw the reason to spend twice as much on Dexcool, when regular anti-freeze does the same job.

 

My information is correct. I've been a GM engineer for the past 15+ years for GM Harrison Radiator division. The only reason why coolants went long life was due to the issue of copper prices going through the roof. Radiators had to be made from aluminum due to cost and weight issues. The old standby green coolants work excellent in a mixed metal cooling loop. The long life coolants have marginal protections. When the HOAT coolant is exposed too long to air, it becomes corrosive in the cooling loop that it's suppose to protect.

Our GM division has seen first hand the effects of long life coolant issues. If anyone replaces the OEM cooling loop components with aftermarket products, there is no guarantee that the HOAT coolant will even work.

GM has had many class action lawsuits for over the past decade dealing with engine and cooling failures due to DexCool problems or DexCool related problems.