05 CTS-V coolant change

It's your engine, transmission, driveline
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kevm14
Posts: 15196
Joined: Wed Oct 23, 2013 10:28 pm

05 CTS-V coolant change

Post by kevm14 »

Pretty routine really. But I have never done it on this car which means this coolant is probably 10+ years old. Not good when it is 5 year/150k stuff. All the talk recently about Dexcool and Northstars made me nervous and even the LS deserves non-acidic coolant.

Just had to remove the center cover on the bottom and slide it out of the way. I did not see a petcock on the radiator (the configuration in this car has the end tanks on the top and bottom which I always found a little odd in a modern vehicle) so I just pulled the lower hose. It started dripping as soon as I loosened the clamp, so no fighting with a stuck hose.

I also flushed like 1/2 gallon of fresh coolant through it so hopefully the majority of it is changed now. I didn't see any junk come out like you'd see with old green stuff in an iron block....this isn't green stuff nor does it have an iron block but I am sure the anti-corrosion properties were gone at this point.

To drive it on ramps I put down two 2-by pieces of wood per ramp, sometimes a mix of 2x3 or 2x4, depending on what I grab. The ramps did not slide forward on the rough surface outside the garage. Inside the garage is a different story though.
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I also did it outside since it was going to rain today, in case I made a mess. I caught it all though.
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It took a while to stop dribbling though.
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To see if a little more would come out I connected my pressure tester and blast 15 psi in there. It did get a little more out at the bottom.
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I ended up a little overfilled. Hopefully after a few cycles the level will drop a bit. If not....meh.

Also the o-ring on my tank cap looked pretty squished. I am actually not sure if it is holding pressure. I ordered a new one just because of my recent experience with the STS. They are like $5.

No other issues. No bleeding required.
kevm14
Posts: 15196
Joined: Wed Oct 23, 2013 10:28 pm

Re: 05 CTS-V coolant change

Post by kevm14 »

Drove in with no issues (in the rain). Temp warmed quickly as usual, and then quickly stabilized. I forgot to check the level or if there was pressure. Meh, I have all week...
kevm14
Posts: 15196
Joined: Wed Oct 23, 2013 10:28 pm

Re: 05 CTS-V coolant change

Post by kevm14 »

kevm14 wrote:Also the o-ring on my tank cap looked pretty squished. I am actually not sure if it is holding pressure. I ordered a new one just because of my recent experience with the STS. They are like $5.
Ha. After I parked I checked the pressure of the upper radiator hose. Squishy! In fact it is not holding pressure. I wonder how long it's been like that. I guess these caps are kind of a maintenance item - they were in the old school, too, FWIW. Also the level is way high...I may still do nothing and if some burps out under summer heat or A/C use then so be it...either that or I can try to suction some out. Unlike certain people's BMWs, there are no alerts for high coolant level...

I should probably check the oil because I haven't checked it since December...
kevm14
Posts: 15196
Joined: Wed Oct 23, 2013 10:28 pm

Re: 05 CTS-V coolant change

Post by kevm14 »

Old cap in hand. New cap installed.
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I got the "GM original equipment" one - the most expensive at a whopping $7. It's a little odd because the Stant (which is $3) actually has graphics more like the original one.

https://www.rockauto.com/en/moreinfo.ph ... 27&jsn=407
kevm14
Posts: 15196
Joined: Wed Oct 23, 2013 10:28 pm

Re: 05 CTS-V coolant change

Post by kevm14 »

Not shockingly, the system is holding pressure now. Definitely validates that these caps can fail.

Coolant level also looks lower. Maybe an air bubble did a thing.
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