ex-quattro PETE

if only there was an M1 10w-40. The closest thing available would be 0w-40.

ex-quattro PETE

I'm not impressed with it. I think M1 does better. Not sure how the price of RP compares to M1... I would not buy RP if it is more expensive than M1.<ul><li><a href="http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=000441">http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=000441</a</li></ul>

jareda80

and my concern is with normal operating temp. I just want a thicker oil in for normal temp range since I'm a burning off the 10W 30 pretty quick. I would probably only run the 15W 50 during the summer months and then a little bit lighter oil in the winter months since it gets damn cold here in Utah.

Dead

"A common misconception is that (the multi-viscosity) oil thickens to achieve a 30,40,50..etc-weight status. In fact, the oil simply maintains the same flow rate, film strength and shear rating as a straight 40-weight oil would offer at higher temperatures."

ex-quattro PETE

Whatever you call it (lower flow rate or thicker), it will be harder for the engine to push, hence some energy will be wasted on pushing the oil around the engine instead of delivering the power to the ground.

I have never seen any manual recommend anything higher than Xw-40 for these engines, unless you're at a race track.

donahoe73

5w-30 in, it felt so much better. No rough idle and the car felt like new. Oh, Mobile 1 was used for both weights.

Dead

It acts like and is equal to what a straight 50w(in this case)would act like at operating temperatures but it does not become a 50w oil. A subtle difference but a difference all the same.
Hence the value of multi vis oils. The ability to flow like a thinner oil and protect like a thicker oil comes from the ability of long chain molecules to be able to unfold as they heat up.

jareda80

so the 0w 40 Mobil 1 synthetic might be the best option to slow consumption?

ex-quattro PETE

I would have to see the specs of the castrol 10w-30 you're running and compare them to the M1 0w-40, but even then, the difference may not be big enough to stop your oil consumption. If your oil doesn't leak out but instead is just "consumed", then there's probably not much you can do about it. I know some of these 2.8 engines like to consume oil - that's just how they are. Even according to Audi, up to 1 quart of oil consumption per 1000 miles is "normal." I can't say I agree with that, but that's what they say.

It was just my opinion that this engine should use an Xw-40 or X-w30 grade oil, because that's what Audi recommends. You can probably use 15w-50 if you want thicker and are willing to accept slight loss of performance and MPG. I'm still not sure whether it will cure your problem though.

I remember reading some people replacing the head gasket or some other parts of the engine to reduce the oil consumption... can't remember now... see if you can find it in the archives or ask again in a new post.

Sorry for not being much help here...

Boba Fett

Mobil 1 5W-30 here w/ no probs. 15W-50 seems it'd be too thick.