A few years ago, they did it as per the procedure. Next time around, I would probably look at a machine flush or flush with water to get it all out.

 

Our local dealer says they use a machine that sucks out the old coolant and replaces with the GM premixed.
If true, that would give you the benefits of multiple drain/refill cycles but much less hassle. I didn't ask how their price for the service compares to multiple drain/refill.

 

Gallons of distilled water are cheap at the grocery store. I drain, flush once with hose water, then a couple times with distilled water, then a gallon of dexcool and top off with distilled water.

 

Think of it this way. If you disconnect a hose and pump in coolant to one end and let the other end drain out, it's easier and thorough.

 

Aha! I remember the days of the old Chilton books. Lots of great information inside of them. I had a 1978 Chevette and my mother owned a 1980. Seemingly, that was my first 'Vette - and was obviously not the best kind of 'Vette that one could own. LOL!!

Regarding the radiator flush, just use the Ranger method. Drain it all out and refill with tap water (some use distilled water, but you're not leaving it in there very long). Repeat the process three times OR until you are draining at just water with no visible coolant. Then fill it with the 50/50 premix (no need to worry about adding the proper amount of water). Run it until it is hot, then keep adding until it is full. Use the turkey baster strategy to drain out the overflow reservoir too. When you add the fresh pre-mixed coolant, don't forget the overflow reservoir. I never did it on my 'Vette because I sold it before I had the chance. The "Ranger" method worked fine on other vehicles.

It's important to use the proper coolant. In the case of the Corvette, it's likely the Dexcool stuff. With our Mazda, it took a different type formulated for Asian cars. A local shop wanted $249 to do a flush on our Mazda CX-30. I bought two gallons of pre-mixed coolant for $20 at Walmart and did it myself. The Corvette might be a bit trickier, though.

For those of you who got your coolant done along with brake fluid, transmission and differential oil, that was probably a wise idea. Make it worth the trip!

 

I wonder how many dealers are actually just doing Drain and Fill per the vette's maintenance manual vs actual Flush and Fill but charging their customers at the full price of a flush and fill? It's especially tricky when the dealers are using language like..."exchanged coolant fluid" or other ambiguous language which does not specifically say drain and fill or flush and fill on the customer invoice/receipt? Always a challenge when going to a dealership for maintenance. Even more interesting is that I believe their own shop manual calls to do a drain and fill and only do a flush and fill if the drained coolant is not translucent or is brown in color (or something to that nature).

 

Has anyone tried DIY without jacking up the car?

 

I know they sell kits with a "T" that caps off or hooks up to a garden hose. I wonder if that can be used?

 

How can you tell without a supervisor patrolling up and down the mechanic bay if the tech is being honest or not? Answer is, you can't. You can, however, get to know people who might know which tech is good. I'm not talking about Bob who has had good luck with John the Mechanic. Chances are he doesn't know what to look for. A year and a half ago, I got an Audi. Asked my friends who have worked there what they think is a good mechanic and a couple of independent mechanics who have worked there. They all gave me a couple of names of very **** retentive when it comes to procedures and that they are also knowledgeable. I knew of an MB tech that was very good especially with older cars. He would do an oil change by using a hole saw to cut a hole in the belly pan so it is easier for him the next time. He also did brake flushes by sucking out the reservoir and filling it back up. Both of which I don't want my mechanic doing. Bottom line. Stop talking about "The Dealership" and start asking about "The Mechanic". Get to know him and treat him good. For my Audi, there are only 2 people who will touch it when I get there. If they are not available, I understand. We reschedule. You people like to throw the keys there, go home and wait for the call to pick up the car. If it goes south, it is "The Dealership" that is bad. That company has a bunch of techs. IF you can't tell me who did what, the review of the place is like 99% of the reviews. Worthless.

Here is what is not as tricky. Ask the important questions like "Labor Rate", "Flat rate time", itemized parts list and cost and what the misc charges are. Under warrant, not my problem. Out of warranty and I'm paying, I demand those answers before employing them. If I am paying, I am not listening to your crap about how much the final charge is. I have told many of the appointment clerks or service advisors who quote me the total price and don't want to tell me what I want to know "I have college edumakashun. I can add, subtract, multiply and divide. I can get the total bill or an approximation if you give me the components of the bill. I don't know how to reverse engineer the components with the total alone.". When you tell me the triple flush is a great deal at $600, I can tell you that at $13 a quart and $200 an hour labor and the job calls for 2,8 hours, you aren't doing it as per procedure.

It is a challenge everywhere if you don't ask the right questions and expect it to be done right. People want to find a good place and expect every tech to be as good, knowledge wise and as good work ethic wise. Not happening. Weed out the bad ones and find the good ones.

What is the cost difference? If it isn't a lot, why bother? The flush is more thorough in that it cleans out more old coolant than must drain and fill.