Update: 10k+ OCI with German Castrol

[ChrisW]

Changed the oil last night on my father's 2.8 30v Audi A6. The oil that was in there was GC, and miles on oil was approx 11,030. Total makeup was about 1-3/4 quarts, not bad for this engine and OCI. I changed out the oil with Mobil 1 0w40. Let me tell you, maybe it's a placebo effect, but the 0w40 is a lot more responsive than the GC. Seems to have more pickup when I floor the car, and going from 65-80 takes a lot less time. Perhaps its the air temp or whatnot, but the 0w40 definatle feels better by use of the ol' butt-dyno. The 0w40 is just as quiet as the GC, definately not noisier. I'll have to see what effect the 0w40 has on gas milage compared to GC. I will also update you guys on consumption compared to GC. After testing Mobil 0w40 for 10k miles, I plan to try SUV 5w40. I will be sending in the sample of the GC to Blackstone either today or tomorrow, and will post results as soon as I get it, along with the TBN. I did use some Redline fuel system cleaner in the latter 1/3 of the OCI, but only maintenence doses; we'll see how much if any it affects the UOA.

 

[glxpassat]

I have the same motor in my Passat. I had the Mobil 0w-40 in it before going to GC. After about 4k miles on the Mobil, I noticed that the hot idle was getting rough. I'm now at 4k miles with the GC and it's definatly smoother than the Mobil was at that point.

 

[Audi Junkie]

I used GC in this motor quite a few times at 6mo/11,000mi intervals. I am doing ARX rinse now at 80,000mi and will be interested in seeing the gunk in the filter. Currently on Delvac 1300S and liking it a lot. I will use some M1 SUV oil by the end of winter to compare with GC. GC does work great in this motor, low consumption. I bet it will be a lot higher on the 0w-40. I really might just use synth just 1 time a year for winter and 15w-40 otherwise. I bet the GC you had in was shot after 11,000 miles, if you put in fresh GC it would have felt better too. It's cool that you are doing oil service on your Dad's car. Looking forward to the UOA. maybe he is due for ARX treatments next summer when using dino oil is better.

 

[ChrisW]

quote:

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Originally posted by Audi Junkie: I used GC in this motor quite a few times at 6mo/11,000mi intervals. I am doing ARX rinse now at 80,000mi and will be interested in seeing the gunk in the filter. Currently on Delvac 1300S and liking it a lot. I will use some M1 SUV oil by the end of winter to compare with GC. GC does work great in this motor, low consumption. I bet it will be a lot higher on the 0w-40. I really might just use synth just 1 time a year for winter and 15w-40 otherwise. I bet the GC you had in was shot after 11,000 miles, if you put in fresh GC it would have felt better too. It's cool that you are doing oil service on your Dad's car. Looking forward to the UOA. maybe he is due for ARX treatments next summer when using dino oil is better.

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Perhaps it was shot after 11,000 miles, but I wonder if the 1-3/4 (closer to 2 quarts) quarts of makeup would have helped it. I would like to do ARX on the car to help prevent the camshaft seals from going again, but the Mann filters are expensive. I was thking about using Wix filters if I were to do an ARX cycle. Doesn't 0w40 initaially have a higher cSt than GC? I know that 0w40 shears down and then thicken up after 6000 miles from reading here before. Hmmm, I'll just have wait and see whats better for the engine, GC, 0w40, or SUV 5w40.

 

[Dr. T]

I agree....even with fresh GC (or anything) it would feel peppier....