mobil 1 5w-40 and 0w-40 are both VAG apporved, although i haven't looked if castrol was, although the M 1 website recommends 0w-40 for A6's but it doesn't matter. i use M 1 but i've heard some really good things about elf excellium, little more expensive than M 1 but it's supposed to be one of the best and it is also VAG approved.
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1999 Audi A6 2.8Q 1995 BMW ///M3 Cosmos Black/ Black
Hmmm... While we're discussing this, how about Mobile 1 5W-30? Just had that put in today because it was the closest thing the dealer had (and I've got three coupons for free oil changes). Not on the official recommended list, but any thoughts to reassure me?
I was asking a European mechanic that was referred to me by a friend today about what oil to use in my 2002 A6 2.7T - he said Mobil 1 synthetic 15-50. I'm getting ready to research -
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'02 Audi A6 2.7t - H&R sport springs, brembo drilled rotors (front), RS6 spoiler, RS6 Hartmann replica rims 17", smoked sidemarkers, debadged '03 Kawasaki 1500 MeanStreak '04 Nissan Quest
15-50 seems REALLY thick. ALL of the articles I've said advised to keep it looser than that. Are you in a cold climate? The recommended list by Audi contains over 200 oils and with only 19 exceptions (each 5W-30), all of them are 0W-40.
To clarify... a winter weight of 15 in a cold climate would really starve the turbos of needed oil until the car is warmed up quite a bit. A lower winter grade will flow more readily when cold. The 50 number will give you greater resistance to breakdown, but if you go synthetic, you're already getting a lot of protection in that regard so 50 seems overkill.
I'm not an oil expert, but here's my understanding...
The first number represents how eaily the oil flows when it's cold. The lower the number, the easier it flows. So, in really cold climates, you want to go with a 0 weight. In warmer climates, a higher number is OK -- maybe a 5. The need to go with a 10 -- which offers higher resistance to viscosity breakdown -- is reduced when you go with a synthetic.
The second number refers to the tendency to resist viscosity breakdown at high temperatures. Again, a synthetic will help you in this regard. If you never drive hard and avoid desserts, 30 would be fine. If you drive pretty hard or are often in hot climates, you'll probably want to run 40. 50 and up tends to be for really harsh environments like the track. San Diego might just be warm enough to merit that kind of weight, but I wouldn't tend to think so. One of the prices you'll pay with these higher grade (i.e., thicker) oils is lower gas mileage. This last fact (and the closer tolerances used to manufacture modern engines) is the driving force behind the move toward lighter oils.
Most of the oils Audi recommends are 0W-40. Great low temp flow in the cold (to get those turbos the oil they need early) and good resistance to high temp brakedown (those same puppies can run pretty hot). They consider 5W-30 an acceptable alternative. Because the second number is lower, you might want to change it more often.
I've actually done a bit of research on this today and there are a LOT of opinons out there. Plenty will contradict mine. FWIW, I've tried to put together the best synopsis I could.
Hmmm... While we're discussing this, how about Mobile 1 5W-30? Just had that put in today because it was the closest thing the dealer had (and I've got three coupons for free oil changes). Not on the official recommended list, but any thoughts to reassure me?
M 1 5w-30 is not synthetic is it?? if it's not synthetic do not use it. That would be alright for a 2.8 although i use synthetic in mine, but because you have a 2.7t you need synthetic for the turbos. non synthetic will ruin your turbos.
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1999 Audi A6 2.8Q 1995 BMW ///M3 Cosmos Black/ Black
I was asking a European mechanic that was referred to me by a friend today about what oil to use in my 2002 A6 2.7T - he said Mobil 1 synthetic 15-50. I'm getting ready to research -
You do not want to use 15w-50. use either 0w-40 or 5w-40, they both provide a wide range of protection in all enviroments. 15w-50 is not recommended by audi and there is always a reason behind it. 0w-40 and 5w-40 are the only M1 synthetic that are VAG approved
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1999 Audi A6 2.8Q 1995 BMW ///M3 Cosmos Black/ Black
M 1 5w-30 is not synthetic is it?? if it's not synthetic do not use it. That would be alright for a 2.8 although i use synthetic in mine, but because you have a 2.7t you need synthetic for the turbos. non synthetic will ruin your turbos.
It's my understanding that Mobile 1 is synthetic. Why do you think it is not?
I have worked for 2 oil companies and still have a lotto learn, if your going to use a 5w 30 must be synthetic, the lighter weight spools turbos faster and still protects well. I like redline but pricy so usually go with mobil 1, my 87 turbo is still running strong at 176000
M 1 5w-30 is not synthetic is it?? if it's not synthetic do not use it. That would be alright for a 2.8 although i use synthetic in mine, but because you have a 2.7t you need synthetic for the turbos. non synthetic will ruin your turbos.
It's my understanding that Mobile 1 is synthetic. Why do you think it is not?
i didn't think M1 made a 5w-30 i figured it was a different mobil product. but still 5w-30 is not vag approved and prolly shouldn't be used.
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1999 Audi A6 2.8Q 1995 BMW ///M3 Cosmos Black/ Black
the official owners manual states my 2000 2.7 T came with 5w-40 but 5w-30 may be used, and they only mentioned regular of sythetic blend. so a full sythetic 5w-30 would be fine
I just had my 2000 A6 4.2 serviced for 80,000 mile at Carlsen Audi in Palo Alto, California (The car has less than 75,000 miles, the service light was on for the annual servie). The mechanic told me that they put in regular oil (Not sure if it is 5W 30 or 5W 40), and it will last for 10,000 miles before the next oil service. He says that Audi engin is different than others. Can anyone confirm this? For an A6 4.2, would you recommend synthetic?
Finding a suitable synthetic oil in the 5W-40 range here in the US that isn't formulated for diesel engines can be problematic. If your oil says anything about 'soot control', then it is more than likely a diesel oil, and not on the approved list. BTW, you have to look at the stamp on the oil and see which industry standards it complies with, just saying 'Mobile 1 5W-40' isn't going to cut it, and more than likely that is a diesel oil.
Now I'm not saying that running a 5W-40 diesel oil is a bad thing, I do it in my Mercedes and Audi regularly when I can't find the VAG approved oil. In fact, a favorite oil of mine in the Shell Rotella T synthetic 5W-40, which is a diesel oil. It doesn't however, have the right additive package in order to address longer oil change intervals for gasoline engines, and thus I don't use it for any intervals longer than 5000 miles, mostly change it around 3500 - 4000 miles.
I did order some european standard Pentosynth 5W-40 synthetic oil off the internet, but I'm not always going to want to do that, and this could get a bit pricey when you add in the shipping cost... so I need another solution...
Whoot! I went to GI Joes last night and found out that they carry Amsoil, including Amsoil's european car formula oil... I love that store!
This is some information I ran across. I have not tried it yet, but considering.
Lubro Moly additives and motor oils, developed over the past 40 years by the German company Liqui Moly GmbH, will give you superior performance modeled after the company's extensive experience with racing cars and boats. Look no further for additives that will keep your car running at peak levels while preventing premature wear and deterioration. These quality products for your German imports are specifically tailored to BMW, Porsche, Mercedes-Benz and Volkswagen-Audi.
Many Lubro Moly products include the exclusive Molybdenum Disulfide (MoS2) anti-friction lubricant. The MoS2 anti-friction agent is an oil-insoluble additive that protects metal parts long after oil and grease have done their job.
If you're looking for an outstanding synthetic, energy conserving motor oil, look to Lubro Moly's Voll-Synthese. This advanced motor oil:
supports the most severe driving conditions, helps with cold starts, gives better fuel mileage, provides resistance to shearing and breakdown, maintains excellent oil pressure and permits superior wear protection.
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2001 A6 oil - 
