Replaced Coolant Reservoir AND paid for Coolant Flush?

Howdy, all. Just a quick question to see if I’ve been had…

I took my wife’s 2007 Pontiac G6 into the shop today because it’s been recently overheating. Plus, it was due for an oil change, anyway. When I set the appointment, I got the oil change package they offered and also asked about a radiator/coolant flush (since it was due for that, as well. Never been done on this car). I told the guy that it was losing coolant and overheating. He said that he could do the coolant flush, but would want to check the system first for any damage.

Today, he did that. He found out the reservoir had a crack in it, causing the leak. Being on a limited time frame, I paid him for parts and labor to replace the reservoir ($173.80). He then said he’d finish that and then do the coolant flush ($104.90). I had the presence of mind to realize that doing one of those takes care of part of the labor for the other, so he bumped down the flush price by $25 (now, $79.90). But it wasn’t until the drive home that the thought occurred to me…

Would swapping out the reservoir necessitate a coolant flush anyway?? As in, is part of the labor for the reservoir replacement draining all the coolant and replacing it when finished? Did I pay $79.90 for a procedure that was included in the other one??

Thanks for your help and thoughts… I’m hoping my suspicions are wrong, as I like the guy I took it to. Never had an issue with him in the past…hoping this isn’t the first.

$104 for a cooling system flush and replacing it with long life antifreeeze is reasonable.

Two separate things, replacing the reservoir requires nothing related to the flush.

I’ll assume your reservoir is pressurized so replacing it involves draining some of the coolant in the engine. However, a flush is a lot more so I’d say you paid a fair price overall.

Fantastic. Thanks, all!

Nope, you can replace the reservoir without removing any of the coolant.The reservoir is just a plastic container that has a hose connecting to the radiator filler neck.

Not always, GM has used pressurized reservoirs:

Insightful is correct. The resevoir is pressurized and part of the cooling system. I suspect you could replace it without losing much coolant but with the long life antifreeze, introducing air into the system is one of the causes of the sludging. You were overdue to have that stuff changed out. The max is five years.

Note that some GM reservoirs aren’t pressurized, like my daughter’s 2004 Grand Prix and this G6, so tardrex is right here. (I always learn more when I’m wrong.):

EDIT: Removed link to washer reservoir…never be in a hurry! I agree, the coolant reservoir on this G6 is pressurized.

Well now I’m confused. That looks like a pressure cap to me, back by the firewall:

I’m confused, too. My older GM cars had pressurized reservoirs. It came in handy when a Cavalier was on its third head gasket and started leaking coolant yet again. I just loosened the reservoir cap, wired it so it wouldn’t fall off and that car went another year losing very little coolant before it totally self-destructed. However, I just looked my daughter’s Grand Prix and it’s definitely not pressurized.

EDIT: Confusion over. The G6 coolant tank is pressurized.

Um, that link was for a washer resevoir not a coolant resevoir. The picture is the same as mine and I can guarantee that it is a pressurized system and there is no radiator cap-a dead give away. The coolant resevoir is in back by the firewall, then the brake resevoir to the right of it. Way up front to the right is the windshield washer fluid resevoir.

That link showed the cooling system reservoir. The orange stuff is coolant.
Here’s a link that shows a better picture of how the system is configured. I believe the link may be to a one-year later model, but you can clearly see the coolant bottle.

Thanks for setting me straight. I’ve edited my previous goofs.

A radiator flush doesn’t offer any significant benefit beyond draining and refilling. If the system has been neglected and the radiator core is becoming blocked nothing short of rodding it out will help. Those flush machines are mostly a money making gimmick.

Just replacing the coolant tank involves either draining just enough coolant to remove the tank without spilling any or not draining any and just putting a pan under the car to catch the coolant that comes out.

A coolant exchange or cooling system flush is more involved.

I wouldn’t have reduced my labor charge on changing the tank.

Here’s the cap for a 2004 Grand Prix.

Looks like a pressure cap to me!

All cooling systems are pressurized. Raises the boiling point of the coolant.


Yep, that’s the radiator cap. We’re talking about the separate plastic coolant reservoir being pressurized (which it is not on a 2004 Grand Prix). I had it all confused before.

The shop went out of its way to please the customer by refunding the $25. So in return the customer should be sure to consider this shop again in the future as needs arise. You now know you have a good shop.