PP 5w30, 7200 miles, 98 Corvette

[Patman]

Here are the latest oil analysis results from my 98 Corvette



Analysis by Wearcheck Canada


7200 miles on oil
May 24 to Nov 14 (6 months)
100,400 miles on the car
Pennzoil Platinum 5w30
NAPA Nascar Select oil filter
Vararam cold air kit (with a cotton gauze filter)
LS1 5.7L V8 engine
Daily driver with a lot of rush hour traffic
7qt oil capacity
1qt of makeup oil added
Oil life monitor was at 0%



Iron 18
Lead 4
Aluminum 7
Copper 1
Chromium 2
Tin 0
Silver 0
Titanium 0
Nickel 1

Silicon 13
Potassium 0
Sodium 3
Boron 26
Barium 0
Calcium 3265
Magnesium 21
Moly 52
Phosphorus 740
Zinc 879
Sulfur 2189
Manganese 1
Vanadium 0
ZDDP 17.2 (not sure what this means, it’s something new)



Oxidation 74
Nitration 57
Sulfation 59
*the three values above are NOT percentages*

Viscosity at 40c 61.5
Viscosity at 100c 11.0
Viscosity Index 172

 

[LargeCarManX2]

I think I would drop it down to 6K because of the Oxid and Nit numbers. The viscosity is dropping too.....Otherwise, she looks SWEET>

 

[Patman]

Viscosity is rock solid actually, as PP 5w30 starts at roughly 11.0. I don't want to drop down the intervals though, as it is now when I follow the oil life monitor to the letter it puts my oil changes every 6 months, so I end up with one in May and one in November, same as the intervals I do with my wife's car too.

I forgot to add that at the end of the interval it was down by a quart, so it burned a total of 2 quarts in 7200 miles.

I did drive it pretty hard this interval though, lots of full throttle runs and one day at the dragstrip too.

 

[HTSS_TR]

Because of stop and go in rush hour traffic, I would change oil when oil life monitor down to 10-15% to be on the safe side.

 

[buster]

Looks good to me. Patman, has it ever consumed that much oil?

Wear metals are very low. With PP, you are also getting good deposit control. I would try their 10w30. Less volatile.

 

[Turk]

I would not go any higher on the OCI.

 

[hate2work]

I would stay with 5- 30, especially since we're coming into the colder months. But I'd begin changing it out every 4 months, or 3 times a year instead of just 2 times.

 

[Yuk]

Originally Posted By: HTSS_TR
Because of stop and go in rush hour traffic, I would change oil when oil life monitor down to 10-15% to be on the safe side.


Why? He doing UOAs, so he knows what the stop and go traffic is doing to the oil/car. As far as I'm concerned he's already on the safe side.

Originally Posted By: hate2work

I would stay with 5- 30, especially since we're coming into the colder months. But I'd begin changing it out every 4 months, or 3 times a year instead of just 2 times.


Why? The wear metals are low and the viscosity is good. What is an extra oil change going to improve?

 

[Al]

Looks pretty good. You have unlimited options here. Who are any of us to tell you to change more ore less often. Personally I wouldn't go higher. But I have kinda' settled on no more than a 7500 mile run.

Broke the 100K mark I see.

 

[Patman]

Originally Posted By: buster
Looks good to me. Patman, has it ever consumed that much oil?




I believe on the 7k interval I did from May 07 to Nov 07 that I consumed around 1.5 qts, so this is the most I've consumed so far. I did drive it pretty hard though, so now that I'm into the cold weather months and won't be going full throttle all that much, I expect the consumption to be less on this next run.

As long as it doesn't go to more than 1qt per 3000 miles I'm not worried. I've heard of some hard driven LS1s that use a quart every 1 to 2000 miles!

 

[Patman]

Originally Posted By: tpitcher
I would not go any higher on the OCI.


Nope, I definitely don't plan on pushing it any further than the oil life monitor says to. There were a couple of intervals in the past when I let the monitor count down to zero and then drove another 1000 to 2000 miles, but that was before I put on the Vararam cold air intake, which lets in more dirt than my previous setup. So the oil gets degraded faster now than it used to.

I don't plan on shortening my intervals either though, this report might not be as picture perfect as some of my prior reports, but it's still showing the oil to be in good shape. Keep in mind that oxidation number is not a percentage, so I'm not afraid of that number.

 

[Patman]

Originally Posted By: Al


Broke the 100K mark I see.


Yep, hit the magic number 2 weeks ago:

 

[webfors]

Looks good. I'm with Buster on the 10w30 if you're going to drive the snot out of it, and spend time at the dragstrip again

Regarding winter oil, you're not going to run that beauty in the winter are you? If so either would do. PP 10w30 has pretty decent winter numbers.

 

[hate2work]

Originally Posted By: Yuk
Originally Posted By: HTSS_TR
Because of stop and go in rush hour traffic, I would change oil when oil life monitor down to 10-15% to be on the safe side.


Why? He doing UOAs, so he knows what the stop and go traffic is doing to the oil/car. As far as I'm concerned he's already on the safe side.

Originally Posted By: hate2work

I would stay with 5- 30, especially since we're coming into the colder months. But I'd begin changing it out every 4 months, or 3 times a year instead of just 2 times.


Why? The wear metals are low and the viscosity is good. What is an extra oil change going to improve?


Remember, he got these numbers by adding oil. That means the wear numbers are skewed, and who knows about this OLM reading.

So, in my opinion, he is living a little bit on the edge doing it this way. He's already told us that he pushed a previous OLM past the 0% mark, which tells us about his maintenance habits, right? And went to the drag strip as well. By changing his oil only twice a year he is leaving himself no "wiggle room".

He would be better off changing it out 3 times a year.

 

[Bill in Utah]

Looks good Pat!

Love the typical normal copper. (you and I seem to be the only ones who can get low single digits in a GM V8)

Thanks for the post!

Bill

 

[OVERKILL]

Patman, you need to go talk to scoobie. Obviously, your 'vette is about to blow up and you need to go buy a Subaru.

*end sarcasm"*

 

[Cutehumor]

results look fine to me with the driving conditions. The OLM at 0% doesn't make me flinch. Corvette OLM designed for syn? since car comes with Mobil 1 from factory?

 

[Audi Junkie]

Yeah, 10w-30 in summer and 5w-30 winter would be the one tweak to make. Top-off oil should be exclusively 10w-30.

 

[Patman]

Originally Posted By: webfors
Looks good. I'm with Buster on the 10w30 if you're going to drive the snot out of it, and spend time at the dragstrip again

Regarding winter oil, you're not going to run that beauty in the winter are you? If so either would do. PP 10w30 has pretty decent winter numbers.


Yep, I drive mine all year round, and it's parked outside overnight so I'm sticking with 5w30 for those occasional mornings when I'm starting it at 0F or less (happens 4 or 5 times a year here in the winter)

 

[Patman]

Originally Posted By: hate2work



So, in my opinion, he is living a little bit on the edge doing it this way. He's already told us that he pushed a previous OLM past the 0% mark, which tells us about his maintenance habits, right?


Excuse me? Are you accusing me of neglecting this car? First of all, the OLM in the 98-00 Corvette is calibrated differently than the 01-04, so the OLM counts down faster in my 98. After reviewing things, they revised the OLM in the newer years without any mechanical changes, so by me going beyond 0% is no different than when the 01-04 guys follow their monitor right to the end. So I'm not neglecting my car thank you very much! Also, I didn't go beyond 0% until after I'd seen a few oil analysis results and determined it was safe. On my longest run of almost 9000 miles, the wear numbers were excellent and so was the condition of the oil. I could still go that far if it weren't for the cold air intake I've got now.

I'm going to stick with my current oil change schedule, as I see nothing wrong with this report that would tell me I'm pushing this oil too far. I see no benefit of a third oil change per year.