I've been lurking on these boards for a while now, and have finally had a UOA performed on my 1997 Passat GLX - 2.8L 12v VR6
This is my first UOA, and the first time this vehicle has seen an oil change interval greater than 5,000 miles since I purchased it. It was purchased with 91,000 miles, and had been maintained at a local dealer using VW factory maintenance schedules. Since I've owned it, I've been using either Lubromoly Voll Synthese 5/40, 0/40, or Mobil1 5/30, 10/30, and 0/40. I have always used Hengst oil filters. The engine has seen over 100k miles using a K&N panel filter, though I've recently gone back to using a paper filter as the rubber seal around the K&N filter began to deteriorate. The engine has also had the ECU remapped (ignition AND fuel maps have been adjusted, redline raised to 7300) for at least 120,000 miles.
The car is used daily 46 miles each way to work, and is the vehicle used for most weekend tasks. Sample was in the vehicle during some of the coldest weather New England has seen in a very, very long time. Periods of -20 (overnight low) to 20 (afternoon high). At least a dozen or more commutes with the temperatures below zero - oil temperatures in the 180s to 190s, and rarely above 200F. Additionaly, my coil-pack was causing misfires in the #1 and #6 cyliders. I replaced the coil-pack in the middle of the test interval. Could the cold and the mis-fires explain slight gasoline contamination, which in turn may have caused the lead reading to be a bit high? I've re-filled with the same oil, and plan to re-test at 7500 miles. I'll post the results when I get them.
*************************************
Blackstone Laboratories Test
1997 Passat - 2.8L VR6
Lubro Moly Voll Synthese 4/50
Mi/Hr on oil: 7,414 miles (approx 3 months service)
Mi/Hr on Unit: 234,074 miles
Sample Date: 03/07/04
Make-up Oil: 1.5 quarts
Comments:
"Since these 2.8L VW engines tend to be bullet proof, we doubt the higher than expected lead found in this sample is from worn out bearings, but it may show the minor gas contamination. If it has been showing up in the oil before now, it may be the babbit at the bearings. The gas contamination may be unavoidable if you operate the engine in-town and the oil isn't getting up to temperature. All the other wear metals read perfectly after 7,414 miles on the oil. The TBN was 4.4, so there is still active additive left in the oil."
Key: samp [univ avg]
Aluminum 4 [5]
Chromium 1 [1]
Iron 15 [23]
Copper 2 [5]
Lead 12 [2]
Tin 1 [1]
Molybdenum 4 [41]
Nickel 1 [1]
Manganese 1 [4]
Sliver 0 [0]
Titanium 0 [0]
Potassium 0 [1]
Boron 89 [62]
Silicon 4 [5]
Sodium 3 [5]
Calcium 1938 [2027]
Magnesium 383 [273]
Phosphorus 772 [765]
Zinc 905 [910]
Barium 0 [10]
SUS Visco @210: s/b 60-76, actual 70.7
Flashpoint: s/b >395, actual 380
Fuel: s/b Antifreeze: s/b 0%, actual 0%
Water: s/b Insolubles: s/b
TBN: 4.4
*************************************
Thoughts? Comments? Do you think that this oil is a good candidate for 7,500 mile change intervals?
Chris
[ March 13, 2004, 11:49 AM: Message edited by: f1forkvr6 ]
This is my first UOA, and the first time this vehicle has seen an oil change interval greater than 5,000 miles since I purchased it. It was purchased with 91,000 miles, and had been maintained at a local dealer using VW factory maintenance schedules. Since I've owned it, I've been using either Lubromoly Voll Synthese 5/40, 0/40, or Mobil1 5/30, 10/30, and 0/40. I have always used Hengst oil filters. The engine has seen over 100k miles using a K&N panel filter, though I've recently gone back to using a paper filter as the rubber seal around the K&N filter began to deteriorate. The engine has also had the ECU remapped (ignition AND fuel maps have been adjusted, redline raised to 7300) for at least 120,000 miles.
The car is used daily 46 miles each way to work, and is the vehicle used for most weekend tasks. Sample was in the vehicle during some of the coldest weather New England has seen in a very, very long time. Periods of -20 (overnight low) to 20 (afternoon high). At least a dozen or more commutes with the temperatures below zero - oil temperatures in the 180s to 190s, and rarely above 200F. Additionaly, my coil-pack was causing misfires in the #1 and #6 cyliders. I replaced the coil-pack in the middle of the test interval. Could the cold and the mis-fires explain slight gasoline contamination, which in turn may have caused the lead reading to be a bit high? I've re-filled with the same oil, and plan to re-test at 7500 miles. I'll post the results when I get them.
*************************************
Blackstone Laboratories Test
1997 Passat - 2.8L VR6
Lubro Moly Voll Synthese 4/50
Mi/Hr on oil: 7,414 miles (approx 3 months service)
Mi/Hr on Unit: 234,074 miles
Sample Date: 03/07/04
Make-up Oil: 1.5 quarts
Comments:
"Since these 2.8L VW engines tend to be bullet proof, we doubt the higher than expected lead found in this sample is from worn out bearings, but it may show the minor gas contamination. If it has been showing up in the oil before now, it may be the babbit at the bearings. The gas contamination may be unavoidable if you operate the engine in-town and the oil isn't getting up to temperature. All the other wear metals read perfectly after 7,414 miles on the oil. The TBN was 4.4, so there is still active additive left in the oil."
Key: samp [univ avg]
Aluminum 4 [5]
Chromium 1 [1]
Iron 15 [23]
Copper 2 [5]
Lead 12 [2]
Tin 1 [1]
Molybdenum 4 [41]
Nickel 1 [1]
Manganese 1 [4]
Sliver 0 [0]
Titanium 0 [0]
Potassium 0 [1]
Boron 89 [62]
Silicon 4 [5]
Sodium 3 [5]
Calcium 1938 [2027]
Magnesium 383 [273]
Phosphorus 772 [765]
Zinc 905 [910]
Barium 0 [10]
SUS Visco @210: s/b 60-76, actual 70.7
Flashpoint: s/b >395, actual 380
Fuel: s/b Antifreeze: s/b 0%, actual 0%
Water: s/b Insolubles: s/b
TBN: 4.4
*************************************
Thoughts? Comments? Do you think that this oil is a good candidate for 7,500 mile change intervals?
Chris
[ March 13, 2004, 11:49 AM: Message edited by: f1forkvr6 ]
