2008 GMC Yukon XL 5w30 M1 syn 8500 miles

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I used Mobil 1 syn Truck & SUV 5w30 with a M1 oil filter. Changed out the factory fill at 500 miles. I changed the oil again after the oil life indicator got down to 10%. What do you guys think? Truck is driving fine no problems. Air filter is K&N.

What kind of worried me was that Blackstone called me up before they released the report to give me a heads up on the high lead and copper levels.

Miles on unit 8500
Miles on oil 8000


Aluminium 20/4
Chromium 3/1
Iron 105/25
Copper 269/66
Lead 82/13
Tin 2/1
Molybdenum 86/71
Nickel 1/1
Manganese 10/3
Silver 0/0
Titanium 0/0
Potassium 8/9
Boron 40/64
Silicon 79/12
Sodium 10/18
Calcium 2258/1861
Magnesium 16/199
Phosphorus 594/702
Zinc 750/873
Barium 0/0

SUS Viscosity @ 210F 57.6/55-62
cST Viscosity @ 100C 9.52/8.8-11.1
Flashpoint degrees F 385/>365
Fuel% Antifreeze % 0/0
Water % 0/0
Insolubles % 0.3/ TBN 2.5
 
I wouldn't start running extended oci's until it is fully broken in. Not sure when that is though, or at least until wear goes down.

I agree, 5K OCI next time.
 
I had almost the exact first UOA last year on my 2007 5.3L Silverado. I went on 3K UOA's with conventional until 30K. UOA's reflect very low wear metals/silicon now. You are seeing a normal Chevy engine during break in.
 
GM V-8's take a long time to break in. I wouldn't be doing exteneded runs until after 20k miles.

Even though this is break in wear, for 'only' 8k miles, those numbers seem scary high. I'd do some short (3k) 'flush' runs to clean this out.

What oil did you replace this with?
 
I would like to see Blackstone's comments on this!

When I break in a vehicle, I run 3K intervals for the first 4 oil changes, then switch to whatever the regular service interval is recommended by the manufacturer.
 
Blackstone's comments:

This oil was put into use while this engine was still going through wear-in, so we expected to see a little excess wear and silicon. We found more than a little of both here, though since the engine is so new, we aren't ready to call either a problem. Universal averages show typical wear metals from this type of
engine after about 5,700 miles on the oil. Most of this wear is from break-in of new parts, while silicon is
from sealers and both should improve next time. The TBN was still okay at 2.5 (1.0 is low), but due to wear,
try just 6,000 miles on the next oil.

addyguy - I replaced it with the same oil 5w30 M1 syn Truck & SUV.

The tech at Blackstone suggested I run the oil for 3000 and take another sample. Thanks for the all the advice everybody. Never had blackstone call me before. I'll be doing 3k intervals until I hit 30k. Should I stick with the M1 syn or go dino since its only 3k intervals?
 
At 3k you could probably just use whatever is cost effective. You won't be wearing out the oil from a mechanical properties standpoint, just filling it up with wear metals so the quality of the oil isn't nearly as big of a deal. UOA's like this are what will keep me from running my relatively new Si to only 6k mi or 30% on the Maintenance Minder for it's third change rather than being tempted to run it out past 10k.
 
That's a heckuva lot of manganese.

This UOA reinforces the need to do a few 3000 mile oil changes before going to extended drains on new engines. They need time to get the junk out.
 
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