Red Line 15W-50 - 721 Miles - 2008 C6 Z06

[hoffmaw1]

I want some input on the UOA from a 2008 C6 Z06 with an LS7, only have used Red Line 15W50 after the 500 mile break-in. I rebuilt the engine in 2023 and replaced the bottom end with all forged internals due to titanium piston wear along with aftermarket heads. The car is only run at HPDE events with minimal street driving. This sample has 8 sessions at Watkins Glen and 4 at VIR. The high titanium might be coming from the spring retainers, and I plan to inspect them, they are the only titanium in the whole engine.

My main question is the high sodium. It has only 50/50 AC Delco Dexcool in it and has always had that. From track usage it uses a very small amount of coolant, maybe 1/8" below the full mark after a weekend. This has been consistent and I top it up back to full line. I would assume a small amount of coolant loss would be normal but I'm not sure. Nothing else indicates any coolant loss.

 

[Brian123]

High sodium levels in a Used Oil Analysis (UOA) can indicate the following issues124:

• Coolant leak: Look for the presence of Sodium (Na) or Potassium (K).
• Dirt particles in the oil: Silicon (Si) levels over 30 ppm.
• Leaking cylinder liner, liner o-ring, or head gasket: Potassium, Sodium, and water levels on the rise.

The above is what I found, others might say run a few UOA's with the oil you are now using.

 

[himemsys]

Could also be a formulation change in the oil. Only way to know is to ask Redline or send a sample in for a virgin analysis. Just be sure the sample you send is from the same bottle you used or with same or similar date code on the bottle.

Another possibility is contamination during the sampling process.

The low potassium doesn't guarantee that coolant isn't getting into the oil, but it does make it less likely.

 

[hoffmaw1]

I agree with you both. I did talk with Blackstone about it and they were saying since there is little potassium and no water that it might not be an issue, especially if I don't see other symptoms like extreme coolant usage. It does use a tiny bit over a track weekend, but I'm not sure how that compares to before the rebuild. I'll reach out to Red Line and see if they tend to have a higher sodium content.

 

[GR_CoB]

Some RedLine oils in the past, as well as some Valvoline oils, did show high sodium in UOAs. It's been a while since I saw that, but back then it was ruled to be a harmless part of additive package.

 

[CarlB]

Coolant loss isn't normal. I'd try to establish where the coolant is being lost. Pressure testing should let you find out if it's leaking out and where.

It's risky to leave un checked, since the leak will introduce air. Which creates air pockets, cavitation, hot spots and isn't good at lubrication.

 

[himemsys]

From track usage it uses a very small amount of coolant, maybe 1/8" below the full mark after a weekend. This has been consistent and I top it up back to full line. I would assume a small amount of coolant loss would be normal but I'm not sure. Nothing else indicates any coolant loss.

1/8" below full does seem incidental. Are you measuring under the exact same circumstances? Engine cold (overnight), same level surface, etc. If you don't top off, does it continue to drop? I try to keep my reservoir at about the halfway point, which gives room for it to expand to full when hot. Is there an overflow hose that could be losing some coolant because you're filling it to the full mark cold? Some things to think about.

 

[TiGeo]

I want some input on the UOA from a 2008 C6 Z06 with an LS7, only have used Red Line 15W50 after the 500 mile break-in. I rebuilt the engine in 2023 and replaced the bottom end with all forged internals due to titanium piston wear along with aftermarket heads. The car is only run at HPDE events with minimal street driving. This sample has 8 sessions at Watkins Glen and 4 at VIR. The high titanium might be coming from the spring retainers, and I plan to inspect them, they are the only titanium in the whole engine.

My main question is the high sodium. It has only 50/50 AC Delco Dexcool in it and has always had that. From track usage it uses a very small amount of coolant, maybe 1/8" below the full mark after a weekend. This has been consistent and I top it up back to full line. I would assume a small amount of coolant loss would be normal but I'm not sure. Nothing else indicates any coolant loss.

View attachment 254534

What events do you do at VIR?