2007 Z06 LS7; unk oil 5.2k mi

[dwaynehicks]

LS7 oil worries

howdy. this is a car i bought and it has been one owner besides me since new that sat a lot. owner said it sat for months and months at a time in the garage and not driven. this is the current oil tested. the engine runs great and has great oil pressure 40-50lbs 0w40 at 850rpm at 190-210*. car makes good power and pulls very hard to redline.

2007 Z06 that was bone stock with 5200 miles at the time of this sample on unknown age of oil.

observations:

1) air filter clamp had rusted and was loose causing a gap at the tb letting dirt in which i have fixed with new clamps.

2) 2 bores had very light scuffing that was visual and not able to be felt (i had the heads off to have them checked). everything else looked fine. i had the oil pan off and didn’t see any metals.

3) oil had a shimmer to it but i’ve seen dust in a lot of my LS cars.

should i look into getting rid of the car? i haven’t sampled it since; i was looking to trade the car in if this is a huge concern.

 

[fantastic]

Not good my friend!
You could continue driving & keep testing a few more 5k intervals just to see IF metals come down.

 

[02SE]

I'm wondering if it was the original factory fill.

Since you had the oil pan off, did you check the rod and main bearings?

 

[dwaynehicks]

well i have the chance to get the car traded in for what, i paid so im not if i want to risk it for another 5k miles.

sure did not check the bearings since i was just doing a new oil pan gasket and timing cover. wouldn’t be surprised if it had only one oil change or two.

feeling like it might be best to lick my wounds and start fresh. sucks cause the car is mint otherwise and runs great.

 

[ka9mnx]

The oil tested was very old and sat for a very long time. I would give that UOA a pass and run it for a while and test it again

 

[dwaynehicks]

The oil tested was very old and sat for a very long time. I would give that UOA a pass and run it for a while and test it again

how can you tell it was old? this is my first oil analysis

 

[wemay]

If this engine indeed has only 5200 mi, it could be break-in. I'd do at least two more UOA to see where it's trending.

 

[ka9mnx]

how can you tell it was old? this is my first oil analysis

You say it's a 2007 with 5,200 miles on it. I doubt the oil was ever changed which would make it very old. And the oil has sat for a long time. You seem eager to get rid of the car without further testing or investigation. That UOA wouldn't scare me not knowing the history of the oil.

 

[dwaynehicks]

If this engine indeed has only 5200 mi, it could be break-in. I'd do at least two more UOA to see where it's trending.

thanks for the sound advice

You say it's a 2007 with 5,200 miles on it. I doubt the oil was ever changed which would make it very old. And the oil has sat for a long time. You seem eager to get rid of the car without further testing or investigation. That UOA wouldn't scare me not knowing the history of the oil.

yes it’s a 2007 that has 5,200 miles on the car / engine. thanks for the advice. just worried i’m going to have to dump $5-7k into a rebuild because of the dry sump/lines/Ti rods etc

 

[ctechbob]

The car is ruined, I'll take it off your hands for cheap!!

Kidding of course.

 

[Patman]

It’s just one UOA here, and from the one lab that we all question in regards to accuracy. You definitely don’t want to use this report as the only reason for getting rid of a great car. Do another UOA on the next oil change from a different lab. Literally any other lab.

 

[grasscutter]

At least it still looks like a Corvette. Can't say the same about the current generation.

 

[edhackett]

thanks for the sound advice

yes it’s a 2007 that has 5,200 miles on the car / engine. thanks for the advice. just worried i’m going to have to dump $5-7k into a rebuild because of the dry sump/lines/Ti rods etc

Yes, a couple more UOA's are needed. To make them useful, you need to flush what's in there thoroughly to eliminate the effects of carryover. I'd suggest running your current new oil 100 miles, change oil and filter again. Run that 100 miles and change oil and filter again. Run 1000 miles on that oil and pull a sample for analysis. See where things are at that point.

Ed

 

[dwaynehicks]

thanks for the perspective everyone. the car has had 3 oil/oil filter changes in the last 1,000 miles and has around 500 on the current fill

 

[oldhp]

You said engine pulls hard up to red line with no noise. Keep changing the oil and enjoy it. As previously said, "at least it looks like a Vette!!!". I agree 100%. Enjoy my friend!!!

 

[edyvw]

Calcium levels indicate that it is older formula. Probably API SM. Zinc and Phosphorus indicate ILSAC oil.
As others said, possibly original oil or it was changed long time ago.

 

[joekingcorvette]

The heads on the C6 Corvette's are notorious for failure. There are lots or articles about this and they are know to blow up without any reason. I would definitely get the heads redone to the correct specifications that prevent failure. They also make an aftermarket replacement head called Frankenstein. A couple of my buddies have blown these engines in their C6 Corvettes due to a very poor head design.

 

[RooflessVW]

The heads on the C6 Corvette's are notorious for failure. There are lots or articles about this and they are know to blow up without any reason. I would definitely get the heads redone to the correct specifications that prevent failure. They also make an aftermarket replacement head called Frankenstein. A couple of my buddies have blown these engines in their C6 Corvettes due to a very poor head design.

Post #1 he's had the heads off and had them checked.

I think he just had nearly 20 year old old in his sump and there is break-in material as well as corrosive wear etc in it.

In any case, the car isn't going to blow up tomorrow and it would be silly to dump it based on a single UOA.

 

[Cujet]

Post #1 he's had the heads off and had them checked.

I think he just had nearly 20 year old old in his sump and there is break-in material as well as corrosive wear etc in it.

In any case, the car isn't going to blow up tomorrow and it would be silly to dump it based on a single UOA.

Correct. UOA's are at best, a tool for monitoring an engine over time. While we can't know the condition of the engine, it is very likely that this is exactly what it seems. A sample of older oil, pulled from an engine that may have been apart not that many miles ago.

Iron levels that high are likely from very light corrosion somewhere, and not wear. I've seen engines with catastrophic cam and lifter failures with 1/3rd that amount of Fe. AND I've seen plenty of LS engines with 90ppm Fe and zero issues what so ever. AGAIN, UOA results are for trend monitoring.

Use a quality robust oil, change it frequently, and enjoy the car. That engine is a ripper!

I'll guess that subsequent UOA results will trend better.

Did you replace the exhaust valves or guides?

 

[dwaynehicks]

Correct. UOA's are at best, a tool for monitoring an engine over time. While we can't know the condition of the engine, it is very likely that this is exactly what it seems. A sample of older oil, pulled from an engine that may have been apart not that many miles ago.

Iron levels that high are likely from very light corrosion somewhere, and not wear. I've seen engines with catastrophic cam and lifter failures with 1/3rd that amount of Fe. AND I've seen plenty of LS engines with 90ppm Fe and zero issues what so ever. AGAIN, UOA results are for trend monitoring.

Use a quality robust oil, change it frequently, and enjoy the car. That engine is a ripper!

I'll guess that subsequent UOA results will trend better.

Did you replace the exhaust valves or guides?

this engine was untouched when i got it (could tell when i had it down to a shortblock in the car)

the car got all new valves, guides, valve springs, timing chain, balancer, ls7 lifters, trays, cam, pushrods, gaskets, seals, hardware, belts, plugs, etc