First time posting here but I would like to share my UOA results from our family's daily driver, a 2005 Dodge Grand Caravan SE Stow-N-Go with the 3.3L non-flex engine.
Comments from the lab are as follows TC7023: Tests indicate the need to CHANGE OIL & FILTER. Silicones (C). Maintain routine sampling. ** Strange additive (B) ** TK3272: Tests DO NOT indicate an immediate need for an oil change. Silicones (A). These tests do not indicate any current problems. Maintain routine sampling. The silicone is high on the first sample because I had just replaced the timing chain on this engine and that means the front cover and oil pan had been resealed (RTV was used on both as required). The strange additive they flagged was the sodium count. Iron wear rates are a touch higher than I would like to see at nearly 1ppm/1000km, however this is our daily driver and is frequently driven around with 5 people in it and I am not gentle on the go pedal - it sees 5000RPM+ a couple times a day at least. Do you guys see anything out of the normal here? I feel like maybe the iron has been elevated because the engine got a new timing chain and timing gears, though I have nothing to back that up with. I am doing UOA as I plan on running extended oil change intervals. I used to have a golf TDI that let me go over 32,000km between oil changes and UOA still indicated the oil was suitable for continued use. That car taught me that 5000km oil change intervals are ridiculous and made me curious about just what you can do. I didn't bother getting the TBN of the oil on these 2 samples as I was just using up the rest of my stock of castrol syntec before moving on to an oil that has a much higher starting TBN. Mostly I was just looking for a baseline for wear rates. I currently have the engine filled with Shell Rotella T6 as it has performed admirably in my track car, in my friend's rally-cross car and several other vehicles that see frequent abuse. I'll post up the next UOA when we get to 15,000km on that oil and I'll do the TBN at that time, however it will likely be 8 months before I have accumulated that much distance. **EDIT** Almost forgot - sampling was done by a local company here in Calgary, AB, Metro-Tech Systems. I don't know how they compare to the big outfits like Blackstone but they have been in business a mighty long time, are reasonably affordable (~$18/sample) and are local so I can drop the sample off and have results in 2 days or less.
Lab Number TC7023 TK3272 Date 2/1/2013 10/26/2013 Unit 124800 136250 Oil 10800 11450 Type Syntec 5W30 Syntec 5W30 Tin 0 0 Lead 1 2 Copper 0.2 0.7 Aluminum 1 1 Silicon 45 18 Iron 12 10 Chromium 1 0.6 Silver 0 0 Zinc 800 724 Magnesium 950 1000 Nickel 0.7 0.8 Barium 0 0 Sodium 111 70 Calcum 1150 784 Vanadium 0 0 Phosphorus 615 533 Molybdenum 60 63 Boron 16 19 Manganese 0.9 0 Viscosity(D445)@100*C 10.02 9.263 Water(D4007) (%v/v) 0 0 Solids(D4007) (%v/v) <0.1 0 Glycol No No Fuel Dilution No No Oil Changed? Yes Yes