[Nickshu]

Driving home today from about an hour away, as soon as I merged on the interstate the oil light came on. Pulled over and checked the oil. It was barely reading on the dipstick. Pulled into the nearest 7-Eleven and added a quart of 5w-30 dino oil (they didn't have synthetic). I did the last oil change 4k ago and checked it at the top of the dipstick after the change. No leaks on my garage floor and the bottom of the engine is bone dry.

What gives? Planning to take to the dealer on Monday....how do they test for this? Compression and leak down tests?

 

[immortal_suby]

The dealer will most likely tell you a quart in 4k is normal consumption. What brand synthetic did you use? I hope it wasn't mobil 1.

 

[Novablue]

I'm sorry but my stuipd question would be how much oil did you put in? Did you account for the oil filter? (did that on my last car )

 

[SC Popatop]

. I hope it wasn't mobil 1.

Please explain your comment. I use Mobil 1, and you've aroused my curiosity. I was of the opinion it's a pretty good oil.
Thanks

 

[SubaruCop]

Please explain your comment. I use Mobil 1, and you've aroused my curiosity. I was of the opinion it's a pretty good oil.
Thanks

+1!

 

[Nickshu]

The dealer will most likely tell you a quart in 4k is normal consumption. What brand synthetic did you use? I hope it wasn't mobil 1.

Yes I used Mobil 1. Why?

Also I am sure I put in enough oil, I recall checking it after filling and I started the car first, so it would have pumped thru the filter.

 

[upflying]

Not checking your oil for 4k miles is not a good idea on any car.
1 qt consumption per 1k miles could be considered normal by many manufacturers.

 

[Freedom1789]

Oil Burner

Both of my 2011 Outbacks have needed additional oil between services. Both were using synthetic and both were past the break-in point. I now carry a quart of oil in the car in the back door pocket -- fits perfect.

 

[rasterman]

Yes I used Mobil 1. Why?

Mobil 1, specifically the 5w30 formulation, is regarded by many to be on the thin side for that weight. In particular, it shears down over time to about the same properties as a 20w oil. Many threads about it on this board, and an infinite number of them on other sites like BITOG.

In many engines, a thinner oil can get past the rings & guides more easily than a thicker oil. This shows up as consumption.

In my opinion, Mobil did this as a marketing move. Mobil 1 is sort of the "gateway drug" for folks switching to synthetic oils- it's the first one most consumers try. And 5w30 is the weight recommended for most 5-10 year old cars on the road today. That's the age range for cars owned by people who are most likely to do their oil changes at home vs. taking it to a dealer.

By making the oil a little thinner, they can better back up their claims for fuel savings.

It's still a great oil, one of the few group IV synthetics available. But like I said, it runs on the thin side. I think you can safely continue to use it, just be aware of increased consumption and be ready to top up between intervals. If that doesn't suit your lifestyle, consider switching to another oil.

I ran it in my XT for a while and noticed increased consumption. After I switched to Amsoil, I see significantly less consumption.

 

[lloyd123]

Mobil 1, specifically the 5w30 formulation, is regarded by many to be on the thin side for that weight. In particular, it shears down over time to about the same properties as a 20w oil. Many threads about it on this board, and an infinite number of them on other sites like BITOG.

Although you mention it, "Motor Oil University" on BITOG seems to contradict the statement about synthetic oils thinning out over time:

When the additives wear out in a synthetic oil it still has the same viscosity. It will not thin as a mineral oil. The fear that some say Porsche has that oils thin when the VII runs out is not applicable to these synthetic oils. These oils will always have the correct thickness when hot and will still be too thick at startup as with all oils of all types, regardless of the API / SAE viscosity rating.

http://www.bobistheoilguy.com/motor-oil-102/

Is Mobil 1 5W-30 different from other synthetics?

Personally I use Castrol Edge with Titanium.

 

[immortal_suby]

Mobil 1, specifically the 5w30 formulation, is regarded by many to be on the thin side for that weight. In particular, it shears down over time to about the same properties as a 20w oil. Many threads about it on this board, and an infinite number of them on other sites like BITOG.

In many engines, a thinner oil can get past the rings & guides more easily than a thicker oil. This shows up as consumption.

In my opinion, Mobil did this as a marketing move. Mobil 1 is sort of the "gateway drug" for folks switching to synthetic oils- it's the first one most consumers try. And 5w30 is the weight recommended for most 5-10 year old cars on the road today. That's the age range for cars owned by people who are most likely to do their oil changes at home vs. taking it to a dealer.

By making the oil a little thinner, they can better back up their claims for fuel savings.

It's still a great oil, one of the few group IV synthetics available. But like I said, it runs on the thin side. I think you can safely continue to use it, just be aware of increased consumption and be ready to top up between intervals. If that doesn't suit your lifestyle, consider switching to another oil.

I ran it in my XT for a while and noticed increased consumption. After I switched to Amsoil, I see significantly less consumption.

Couldn't have said it better. Mobil 1 has shown over time to disappear in subaru motors.

 

[4wheeldog]

Couldn't have said it better. Mobil 1 has shown over time to disappear in subaru motors.

In my reading, Mobil I seems to have a tendency toward oil consumption in TURBO subie motors, not NA motors.

I have used Mobil I 5/30 and 0/30 for years in a variety of Toyota motors. None has used a drop. My Outback 2.5 now has 19k miles. It has not used any since the initial change, at 1100 miles, to Mobil I.

Some engines use some oil. Some are because the break in did not put enough pressure on the rings. Some are just a product of production tolerances. Checking your oil regularly, at least until you have established a record of oil consumption, is a really good idea.

 

[rasterman]

Although you mention it, "Motor Oil University" on BITOG seems to contradict the statement about synthetic oils thinning out over time

My opinion regarding shearing over time is heavily influenced by used oil analyses- ones I've had done as well as ones shared by others on the web. Nearly all of them were from turbo engines, which tend to be much harder on the oil than a straight piston mill.

 

[gomjabber]

The only engine I have ever owned that used oil was the 3.2liter in the isuzu rodeo. Oh yeah, it also used a lot of intake manifold gaskets too.

You guys make me paranoid, I went and checked mine right now and I am half way through my 3rd oil change with still no oil usage. Mobil 1 here.

 

[rasterman]

Some engines use some oil.

I quoted the part I think is most significant. Even identical engines built on the same day will show different characteristics. Some of that you can put down to break-in, some of it to usage, and some of it to extremely tiny differences from one engine to the next.

I don't think there is any one perfect oil- it pays to try a few and see what works for your machine and the way you want to use it.

Staying ahead of leaks & consumption is paramount. Any oil is better than none.

 

[4wheeldog]

I do have some anecdotal experience on how one might get a motor that uses some oil to stop.

I have a motorcycle that has the reputation for using some oil (A BMW R1150RT). When new, they all tended to use some oil. It takes 15k to 20k for usage to level out to a minimum. The consumption in mine tapered from 8 oz per 1000 miles down to about 3 oz per 1000 by 18k. This was on Mobil I 15/50 from 6k on. I then, on advise from a friend, tried a change with Redline 15/50. Consumption dropped to almost zero, and continued even after changing back to Mobil I. The bike now has over 75k miles. About every 25k, I will notice a tendency for it to start using a bit of oil again. I then do a change to Redline, consumption drops to virtually zero again, even after going back to Mobil I.

The theories on why this works vary. My buddy thought that Redline has some "Abrasive" quality that brought the rings in. Personally, I think that Redline has a load of additives that chemically attack whatever deposits there are that make the rings a bit sticky. I don't think that those additives are necessarily good, long term. But, if they can get the rings freed up so they seal better, the occasional use seems worthwhile. YMMV. Good luck.

 

[Nickshu]

The dealer will most likely tell you a quart in 4k is normal consumption.

Yep. Called dealer this AM. They said this level of oil consumption is "normal". I think its some pretty crappy engineering for a new engine to use that much oil, but it is what it is.

1 qt consumption per 1k miles could be considered normal by many manufacturers.

Really? I have owned many cars in my lifetime and have always done my own oil changes. I have never had a car use that much oil. At most 1/2 quart in 5K miles, and that was only when the engine had north of 150K on the clock. Heck my 30 year old Porsche doesn't use that much oil and it's never had an engine rebuild!

Like I said, it is what it is. I guess I'll check the oil more often. This is my first asian car, all my other cars I have owned have been European or American. Maybe less sloppy engineering on those cars than on Subaru. Guess I'll switch to Amsoil and keep an extra quart in the back.

 

[gomjabber]

Yep. Called dealer this AM. They said this level of oil consumption is "normal". I think its some pretty crappy engineering for a new engine to use that much oil, but it is what it is.



Really? I have owned many cars in my lifetime and have always done my own oil changes. I have never had a car use that much oil. At most 1/2 quart in 5K miles, and that was only when the engine had north of 150K on the clock. Heck my 30 year old Porsche doesn't use that much oil and it's never had an engine rebuild!

Like I said, it is what it is. I guess I'll check the oil more often. This is my first asian car, all my other cars I have owned have been European or American. Maybe less sloppy engineering on those cars than on Subaru. Guess I'll switch to Amsoil and keep an extra quart in the back.

It hasn't been my experience that most cars from toyota, honda, use that much oil. With 16k on the odometer my subaru is using no measurable oil.

 

[Sandroad]

I can't find any real documentation from testing for the statement below about Mobil 1 5-30. I would appreciate it if someone could post that info.


"In particular, it shears down over time to about the same properties as a 20w oil."

 

[foxrider68]

I'm going to be using Amsoil on my 13 as the Amsoil 0w-20 is technically thicker than Mobil 1 0w-20. I've heard of some cases where a motor would burn Mobil 1 but not Amsoil. I got a free 6 month membership at Amsoil that will give me dealer pricing. I think 0w-20 OE will cost me $4.30 a quart which is cheap but shipping sucks. I'll probably see if a bulk order brings shipping per quart down.