This is the factory oil drained from a 2024 Chevy Tahoe Duramax 3.0L LM2 diesel engine. The factory oil was drained at 3,000 miles. There was no oil consumption despite pulling a small trailer 2,200 miles. I have a Banks iDash which I use to monitor the EGTs and keep sustained EGTs lower than 1,150°F, as to not consume oil engine oil and it works. This engine, similar to the 6.6L Duramax, will consume oil if sustained EGTs are allowed to be higher than 1,150°F. The average EGTs were probably 950-1000°F while pulling. I did not pull the trailer over 70MPH the entire trip and pulled in 8th gear, which is 2,000 RPMs. If allowed the computer will pull the trailer in 10th at 1,600 RPMs and 1,200°F all day long. The peak EGTs I saw were on an uphill onramp with a heavy foot and reached 1,500°F for a few seconds.
The OEM oil was replace with HPL 0w-20 Dexos D, which I asked them to formulate and blend, as they didn't previously have a Dexos D. Thank you @High Performance Lubricants !!
My observations of EGTs and RPMs if I let the computer control the trans is that when the EGTs reach > 1,250°F, the trans will shift to a lower gear. This is different from the 6.6L which will churn away all day at 1,350°F EGTs if you let it. GM seems to have changed the programming on this engine to shift into a lower gear earlier in an attempt to keep the EGTs down and reduce oil consumption.
The factory oil filter is the first factory filter I have ever removed that wasn't grossly over tightened. Nice work GM. The debris in the filter is a bit shocking, metal and sealant mostly. The factory filter was a PF66 and was well constructed, but is really small.
Note the debris in the filter element:
A PPE oil filter went on to replace the GM PF66. The PPE, filter being much larger, has 40% more filter media and is a heavy duty well constructed filter. The PPE filter even has a magnet in the base.
The OEM oil was replace with HPL 0w-20 Dexos D, which I asked them to formulate and blend, as they didn't previously have a Dexos D. Thank you @High Performance Lubricants !!
| Sample Information | ||
| Sample Date | 5/4/2024 | 5/5/2024 |
| Machine Age miles | 3,000 | 3,050 |
| Oil Age miles | 3,000 | 50 |
| Makeup oil quarts | 0 | 0 |
| Filter Age miles | 3,000 | 50 |
| Oil Changed | yes | no |
| Filter Changed | yes | no |
| Brand | OEM | HPL |
| Viscosity | 0w-20 Dexos D | HPL 0w-20 Dexos D |
| Wear Metals | ||
| Iron | 38 | 7 |
| Chromium | <1 | <1 |
| Nickel | <1 | <1 |
| Titanium | <1 | <1 |
| Silver | 6 | <1 |
| Aluminum | 4 | 3 |
| Lead | <1 | <1 |
| Copper | 10 | 2 |
| Tin | 2 | <1 |
| Vanandium | <1 | <1 |
| Cadmium | <1 | <1 |
| Additives | ||
| Boron | 40 | 106 |
| Barium | 3 | 2 |
| Molybdenum | 27 | 71 |
| Manganese | 2 | <1 |
| Magnesium | 15 | 876 |
| Calcium | 1781 | 1167 |
| Phosphorus | 879 | 798 |
| Zinc | 927 | 821 |
| Contaminants | ||
| Silicon | 104 | 23 |
| Sodium | 2 | 0 |
| Potassium | 5 | 3 |
| Fuel % | <1 | <1.0 |
| Glycol | NEG | NEG |
| Soot% | 0.2 | 0.1 |
| Fluid Condition | ||
| TBN | 7.9 | 12.54 |
| Viscosity | 8.2 | 8.9 |
| Oxidation | 11.2 | 0(30) |
My observations of EGTs and RPMs if I let the computer control the trans is that when the EGTs reach > 1,250°F, the trans will shift to a lower gear. This is different from the 6.6L which will churn away all day at 1,350°F EGTs if you let it. GM seems to have changed the programming on this engine to shift into a lower gear earlier in an attempt to keep the EGTs down and reduce oil consumption.
The factory oil filter is the first factory filter I have ever removed that wasn't grossly over tightened. Nice work GM. The debris in the filter is a bit shocking, metal and sealant mostly. The factory filter was a PF66 and was well constructed, but is really small.
Note the debris in the filter element:
A PPE oil filter went on to replace the GM PF66. The PPE, filter being much larger, has 40% more filter media and is a heavy duty well constructed filter. The PPE filter even has a magnet in the base.
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