Why would you put Dexcool in a Toyota when the gallon bottle simply states that it's used for GM vehicles? That's your own fault.
I can simply lift the hoods on my GMs and see Dexcool clearly written on the cap. Maybe it's simple owning GM. My oil cap says Mobil 1 only. When you own cars 50-70k, you don't dump in any old thing. All this can be prevented by asking simple questions and/or reading the owner's manual. I would rather hear you refilled with water in a non freezing climate than picking up Dexcool that was very likely mixed with green. A major mistake!
This little link here; www.sancarlosradiator.com/dex-cool_pics.htm pretty much shows and tells you the horrid nightmares that Dexcool can cause, and in my opinion why GM should have never gotten involved with Texaco, who actually manufactures this stuff.
Notice that the Blazer in the pictures also switched it out.
As somebody who works on cars quite often, I too have seen this many times, mostly on the engines in the comment listed above.
Change it every 2-3 years. No way would I take a new late model car within factory warranty and put green in there. Same with the Mobil W on my refill cap under the hood. Manufacturers can void warranties over operator poor judgement.
Our current GM is 11 years old with the original Dexcool that came in it. It still looks fine and tests out fine for protection against freezing. I never change anti-freeze or flush a system unless I see evidence of a need to do so. None of our GM vehicles has ever had a single repair or cooling system issue of any kind. Just what "horrors" is Dexcool supposed to cause and when? My highest mileage on the original coolant in a car is just under a quarter million miles. Never an engine, radiator, or cooling system problem. Not even radiator hoses replaced or a water pump.
I have owned 5 Corvettes with newer gen utilizing Dexcool. I have yet to flush out crud with a 2 1/2 year changeout. In fact my recommendation is to flush all types and do your car justice on a frequent basis. I change my brake fluid every 3 years due to moisture. Probably most try to use false economy with spread out intervals. It's often a mistake. The only concern I have is with transmission fluid changes. Drop the pan and introduce dirt upon opening it. I always buy high quality filters and like NAPA Gold. I use K&N reusable filters on my cars and trucks. I am careful not to over oil, and dry thoroughly so I don't light up a check engine light with the electric MAF. I read my manuals and don't overstretch intervals. Even as a high performance enthusiast, I have yet to buy a replacement domestic engine or transmission since sitting behind the wheel in 1969.
There were never problems with Dexcool in GM models with aluminum engine blocks such as your 11 year old GMC Envoy, or even the newer Vettes.
Just curious, was the quarter million mile car you are talking about the 77 Buick LeSabre you mention all the time? Remember back then they used green coolant.
Please, I'm a big GM fan, but I can swallow some pride and admit that Dexcool sucks.
"So why not flush and go universal yellow?"
"Why even remotely use green?"
Because the green was on sale at the store at the time. No way was I going to put Dexcool back in after flushing it 3 times within a year and a half, and getting sludge water 3 months later. Like I said, it has been three years since I switched to the green on my mother's 97 LeSabre, and not a problem since, no leaks or disintegrated coolant.
As far as universal yellow; a few months ago I did a flush on my 96 Town Car. 176,000 miles before that it always had regular green, but I used the universal manufactured by Prime.
"And how do you flush late models that do not even have radiator caps?"
Just take the hoses off. Yes, it is a pain and more complex, but it's also another example of how newer cars are much harder to work on. Supposedly Dexcool has improved its formula, therefore I wouldn't worry about doing early flushes on newer models.
Yes, I was referring to the '77 Buick LeSabre. It was an awesome car, and probably the most reliable our family ever had overall. It was a used rental car that was bought with about 30,000 miles on it. And the point wasn't that it had Dexcool, but that it never had the coolant changed. I have seldom ever changed coolant or flushed the cooling system in any of our cars as long as it looked clean and tested OK for freeze protection. I'm a big believer in not "over maintaining" a vehicle. I do regular oil changes, of course, but never change coolant or transmission fluid unless there are problems evident. I've seen a number of transmission failures in cars (especially GM) immediately after a transmission fluid change. The owner's manual on many GM cars states very clearly NOT to change fluid unless your vehicle is used for very heavy towing.
Our experience with our cars has been so good that I plan to stick with my "hands off" policy. We simply don't have problems with any of our cars, whether they are Ford, GM or Chrysler. They basically run forever. We have never traded a vehicle because it was "worn out", but just because we finally get bored with it. So far our GMC is giving the Buick a run for its money as our most reliable car ever, and my wife plans to keep it indefinitely. It is still like new after 11 years.
Anyone ever follow a hands off car? I have seen oil burners, blue smoke gems, oil pans you use a scraper on, radiators that have pinhole leaks, dried out seals dripping on the floor. And cars that look lived in, slept in, ate in and spillage all over at my parents shop. Yet you turn the key and they run.
It certainly doesn't help the resale element as well. Labor is high and even parts for do it yourself individuals. Oil and fluids are cheap in comparison. And being stranded isn't a fun time.
I have a battery that lasted 7 years and is always on a battery maintainer. Today I am buying a new replacement, even though it starts perfect. I know it's due, and rather than be stranded, it's logical. Better to be proactive than sit along a desolate roadway at night. Especially in this time and age.
Modern cars are ALL basically "hands off" cars. Other than oil changes, no modern domestic requires anything other than tires and batteries. All of our cars have million mile air filters that never need changing. I use only synthetic oil, so sludging doesn't happen. We never tow anything, so transmission fluid never needs changing. Tune-ups are recommended at a around 100,000 miles, but unless there is evidence of a need for it I'd keep going. Coolant changes are only needed when the coolant is indicating contamination or loss of freeze protection. Radiator hoses can be easily checked for deterioration. In the past three decades I've never replaced a radiator hose or a drive belt on any of our cars. I regularly use belt dressing on belts to keep them like new.
Our cars simply don't use oil. Our Dodge with 240,000 miles never used a drop or smoked. Its only repairs were two brake jobs, two timing belts and one heater hose.
I've seldom had a problem with resale. All the cars I have bought used over the past three decades have been sold for what I paid for them, with only one exception that was bought nearly brand new. One Dodge truck I bought new was sold after five years for 92 percent of its original purchase price. I'd call that pretty good resale value.
I don't use dressings on belts as it makes it worse with cold weather squeals. I changed the serpentine belt and idlers at 50k with factory GM belts. The squeal returned. So I went with the grooved Gatorback belts.
As far as maintenance, it's possible to work on cars if you go online and YouTube repairs. You can buy an electric lift kit for a garage today for 2k. You still have brakes and other wear repairs that can be done as well. Scanners for home use are also not overly expensive. I bought 02 sockets, as I have one or more of 4 02 sensors on my car that needs replaced. I just bought the sockets at Harbor Freight.
There are lots of repairs that can be done by owners, but with the incredible reliability of modern American cars, most people trade well before any repairs are needed. Absolutely nothing at all should be required before 100,000 miles, and little if any before 200,000.
A mechanic friend and I were talking last week about how the new high-quality ceramic brake linings used in American cars can easily last 200,000 miles, and most hoses and belts will last that long as well. Since the early 90's, none of our cars has ever required anything at all, other than tires and batteries.