Okay, maybe I'm nuts...

[moribundman]

Since I plan on changing the oil in my 2.8 12 Audi soon, and because I'm not going to use M1 0W-40 again, I decided to just get some GC and top off with that. Now, quite frankly, I rarely believe in any hype, and I'm not favoring any oil under XW-40. So I dumped a bit over 1/2 quart of GC in, and the motor sounds better. I asked my girlfriend if she noticed anything, and she said it sounded quieter (I hadn't told her what I'd done). I don't think both of us are imagining this. If 1/2 quart of GC on top of 4.7 quarts of M1 makes a noticeable improvement, then I must wonder if GC is really the Holy Grail of off-the-shelf oil.

 

[Leo]

I cant see how 10% GC could make so much difference!! Hmmmm

 

[Baveux]

"Maybe" doesn't apply here

 

[moribundman]

Yeah, I tend to agree.

 

[c502cid]

No, when it comes to oil, your not nuts. My old Honda ran better and quieter when I even thought about adding Auto Rx!

 

[JoggingGuy]

quote:

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Originally posted by c502cid: No, when it comes to oil, your not nuts. My old Honda ran better and quieter when I even thought about adding Auto Rx!

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One of the guys over on the Ford trucks site has a signature line that says "You're not crazy, you're one of us"

 

[Dr. T]

moribundman, I've already posted (and so have others) that IMHO, Castrol has a better addative package (and so do other oil co's) than M-1. So it is without surprise that the engine is quieter with some Castrol added (even if it's only 10%). Not sure if M-1 has a poor addative package because it depends exclusively on it's PAO formulation (to save costs) or otherwise...but, it's obviously NOT just the viscosity as the GC is thinner than M-1 0-40.

 

[moribundman]

So, I'm not crazy, doctor? I think you may rememeber that I used to use Syntect 5W-50 (The oil shunned by so many) in my engine from the first oil change until the car had about 100k miles on it. And I did so with very good results and 10k miles O/C intervals. I only switched to M1 when I found out that the Syntec was a group III oil. I've also never been fond of anything thinner than an XW-40 oil, at least not in my European cars. The Castrol 0W-30 really took me by surprise, and I find it hard to believe that 1/2 quart can make an audible difference. And that oil seems thin as water! Then again, my engine does sound like a sack of nails with M1 0W-40. I'm now tempted to use GC 0W-30 as my next oil. After all, it meets all required specs for my motor.

 

[crashz]

After a defective filter issue, I can say that I'm very pleased with the sound and performance of my engine with GC in it. Many Castrol products failed to impress me and one even failed to perform adaquately, so I had a grudge to start with. When I put GC in my truck I must have had a defective filter because it made the truck tick at start up. This further fueled my dislike of Castrol, until a member here suggested changing filters. I replaced the Motorcraft with a Napa Gold and Viola! It runs beautifully and with out any noise at start up.

 

[Dr. T]

Yeah I remember...I think you should go for it. The only thing I'd be concerned is increased consumption over the 5-50. It would be great to do a comparison both real-life feedback and a UOA. My engine too sounded like a trash can with the 0-40. Worse than the M-1 5-30 and 15-50...don't know why...

 

[nick778]

quote:

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Originally posted by Dr. T: moribundman, I've already posted (and so have others) that IMHO, Castrol has a better addative package (and so do other oil co's) than M-1. So it is without surprise that the engine is quieter with some Castrol added (even if it's only 10%). Not sure if M-1 has a poor addative package because it depends exclusively on it's PAO formulation (to save costs) or otherwise...but, it's obviously NOT just the viscosity as the GC is thinner than M-1 0-40.

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I fail to understand your basis for saying GC has a better additive package than M1. Both contain similar amounts of zinc, phosporous, etc with calcium being about 400 ppm more and Mg about 90ppm more. However, M1 contains Boron and Moly both of which are absent in GC. IMO, if GC is any better, it is primarily due to the quality and viscosity of its basestock and hence the A3 rating. [ January 06, 2004, 03:35 AM: Message edited by: nick778 ]

 

[Quattro Pete]

mori, Is it possible that your engine was slightly louder before because it was running 1/2 quart low on oil? Once you topped it off, it quieted down. Maybe it would have done that even if you topped off with Canola?

 

[Patman]

quote:

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Originally posted by Quattro Pete: mori, Is it possible that your engine was slightly louder before because it was running 1/2 quart low on oil? Once you topped it off, it quieted down. Maybe it would have done that even if you topped off with Canola?

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I think this makes the most sense of all, good catch Pete!

 

[Dr. T]

Both the M-1 0-40 and the GC 0-30 have an A3 rating. So it's hard to knock either oil's base oil. However, simply looking at a VOA in order to determine the proprietary addative package is like looking at the ingredients of your favorite cookies and attempting to make them yourself. It ain't gonna happen. Each oil company has their own recipe that's not visible on a VOA or a UOA.

 

[moribundman]

Hey Pete, the oil level was between "min" and "max," which as you know isn't exactly low, but just 10% of the whole oil volume. That's always the point when I top off, and I've never before heard any difference in engine noise as a result of topping off. However, I've never added any other oil brand or viscosity than what was in the engine. That was the first time. Since I'm not the only one wo heard a difference, I'm inclined to attribute the change in noise level indeed to those 10% of GC. But I really have to say, my engine sounds unbelieveably bad with M1 0W-40 compared to the two other oils I've used in the past (OEM synthetic fill and Syntec 5W-50). [ January 06, 2004, 03:51 PM: Message edited by: moribundman ]

 

[Quattro Pete]

Well, I'll be switching to GC at my next oil change, so I'll see for myself if you're nuts or not. Until now it's always been M1 (0w-30, 5w-30, and now 0w-40).

 

[moribundman]

Well, I still think I'll go with a 5W-40, but if I can't find one to my liking, then I'll just use the GC. Let me know what you think when you have the GC in your four boinger. Say, how's your 1.8T sound with the 0W-40?

 

[Quattro Pete]

It sounds the same as with other M1 grades I've tried, although it feels just a tad bit more sluggish, but then again, maybe I'm just imagining it, too. FYI, there's a new UOA of Pentosin 5w-40 on the UOA forum, in case you haven't seen it yet. I guess this one is hard to get, but the poster is from Cali as well. [ January 07, 2004, 07:33 AM: Message edited by: Quattro Pete ]

 

[moribundman]

Thanks for the heads-up, Pete. Pentosynth is available online. Nice thing is, it comes also in a 5 liter jug.