QS HMFS 5w-30 - 2004 Silverado 5.3 - 4,085 miles on oil... 48,000 miles on engine. Silicon issue...

[mrsilv04]

Wasn't expecting the 55ppm spike in the silicon at all. Is usually in the 10-15ppm range. Only work that has been done on engine, was to install a new oil pan at the last oil change. Air intake was not disturbed at all, to my knowledge. However, I removed, checked, and reinstalled the air intake last night. It was clean with no issues found. Air filter is a few years old, but is still completely serviceable. Have a new filter on order anyway. However, I can't image a 4-5x spike coming from an air filter over just 4,000 miles.

Could have some gasket tack/sealant caused this silicon spike, when the oil pan was installed? Also, no idea if the 'mechanic' actually cleaned out the new pan, by spraying with parts cleaner and wiping it out before installing it (he likely didn't).

Also not thrilled about the 1.6 base number after only 4,085 miles. This vehicle only towed a 5x10 utility trailer about 100 miles on this change. That seems a tad bit low, considering the easy and relatively short 4,085 miles of use.

 

[GMBoy]

The silicone most likely came from the RTV used in the oil pan repair - that will go away. The TBN is low but it is not uncommon for an oil to lose TBN but get around 1-2 and stay there for some time. I would agree I would have rather seen a 3-4 at that mileage.

 

[twX]

The low TBN is unusual. Maybe they used an acidic parts cleaner when they replaced the oil pan or something? I'd do another 3k miles or so and then do another UOA.

Lead and copper aren't flagged but they seem very high, especially lead. Do you know what's normal for these engines? Could be corrosive wear.

 

[mrsilv04]

The low TBN is unusual. Maybe they used an acidic parts cleaner when they replaced the oil pan or something? I'd do another 3k miles or so and then do another UOA.

Lead and copper aren't flagged but they seem very high, especially lead. Do you know what's normal for these engines? Could be corrosive wear.

Lead has always been an issue with this engine. It has averaged 19ppm over the last 6 UOA's, so this reading is not unusual. Much of the problem is that it is a Jasper "remanufactured" unit... it is the second warranty replacement, after the original Jasper engine and the first warranty replacement both failed. High quality stuff here, folks.

The current reading of 21ppm of lead is low, compared to what it was for the first 20,000 miles.... LOL.

Copper averages 10ppm over the past 6 changes, so it is (unfortunately) typical for this engine. Again, it's a Jasper unit.

 

[mrsilv04]

The silicone most likely came from the RTV used in the oil pan repair - that will go away. The TBN is low but it is not uncommon for an oil to lose TBN but get around 1-2 and stay there for some time. I would agree I would have rather seen a 3-4 at that mileage.

I assume the mechanic used the FelPro "PermaDry Molded rubber" pan gasket that I supplied for the job, and hopefully not RTV...