What Oil to use?

[r34dy2fly]

Hello everyone.

First I'd like to say that this is a great informative site on Oils and I have learned so much from lurking on this site that my brain started melting down after about 2 hours of reading. With that said, I figure I ask the veterans of Oil to lend me their advice on what type of Oil I should be using for both my vehicles.

First Vehicle: 2001 Porsche 911 Turbo.
I have stuck with Mobil 1 pretty much the whole life of the car. Between the turbos and the fact that its a Porsche, the car is VERY tough on oil and talking with many different members on a different site I figured I would be safe until I read that they changed the additive packages in Mobil1. The car now currently has just shy of 62,000 miles and I just recently moved over to Pennzoil Ultra 5w40. This is my weekend warrior and doesn't really get driven all to much except for when I go cross-country. I'll try to get a UOA on this vehicle once I get back in May after I drive back from GA. Anyone have any experience on this vehicle as to what oil would be best for my driving habits? If I take this car out.... its definitely going on a spirited run unless I'm heading to a different state and even still...

Second Vehicle: 2007 Subaru Impreza
This is my daily. I actually just picked this up and it really doesn't get much mileage either. I usually just drive this to get to work which is only about 5 miles each way. Honestly, I take this car out to go eat, hit the gym, and just about anything else but even still, I wouldn't normally drive it as much as anyone else seeing how everything is so close. Not really stop and go around here in Louisiana. Now, I just recently picked this up and planned on moving this over to Pennzoil Ultra as well. I've read to try 5W30 on this vehicle as its what the manufacturers state. Anyone have any experience on what oil works well for this car? Its not turbo-charged so it should be fairly easy on the oil. I honestly probably baby this car more than the Porsche. I don't really beat on it all to often and its mainly just to get me to where I need to go. Miles are around 62000 miles as well. I'll try to get a UOA for this when my kit arrives.

Anyway, I hope to learn from you all so thanks in advance for the advice.

 

[dtt004]

Hi.

It is next to impossible for you to know when Mobil will change their additives. Since the base stocks of today's lubricants are so similar, additive packages serve to differentiate the brands and thus are closely guarded. The only way to see how additives have changed is to compare an oil analysis with another oil analysis and examine the changes.

I don't have a clue why other sites' members are saying to hold off on Mobil 1. Mobil 1 comes as the original factory fill from Porsche, just like Ferrari comes factory filled with Shell/Pennzoil. Although it could be due to contracts and or technical partnerships, Porsche should have great confidence in that oil if they recommend it.

In my opinion, Mobil 1 is a great choice and you should stick with it. Likewise, Pennzoil Ultra is also a great choice and you could stick with that. I doubt you will feel or notice the difference; both oils are well engineered and will last inside any engine.

Turbocharged engines are hard on oil because the oil is used to lubricate the bearings in the turbocharger itself. Unlike a supercharger, which almost always uses a dedicated oil, a turbocharger draws oil from the engine pan. That's why it is important to maintain good driving habits with a turbocharged engine.

The most important thing you can do for your turbocharged engine, and to make it and its oil last longer, is to idle the engine before shutting it down. Or you can use a turbo timer which does it for you. Since the turbocharger takes time for it to stop its 30,000+ rpm rotation, oil needs to be freshly supplied to cool it down. It also will extend the life of your engine oil.

A synthetic oil as you know offers advantages such as extreme temperature shear stability and low temperature ease of starting. They are also engineered in the lab, which enables the addition of a higher amount of additives. Conventional oils of today are approaching the performance of synthetics, but if synthetic is what the owner's manual says, I would recommend it.

The only turbocharged engine I own is in my 1991 MR2. It has a pretty basic setup as far as turbocharged and engine technology go, but I still follow the same deal about idling. It prevents oil coking in the bearings of the turbocharger and extends engine oil life. I use conventional oil, because I believe it is up to the task.

So. As long as the engine oil is of the correct viscosity and carries the correct specifications, it is good to go. You can use Mobil 1 with confidence, as Pennzoil Ultra too.

 

[HTSS_TR]

I think Mobil1 0W40 is in the Porsche recommended oil list for your 911 Turbo. Your current Pennzoil Ultra 5W40 is a good choice, another choices are Redline 5W40 and Amsoil AFL 5W40.

Since the Subaru is used for in town drives and fairly short distances, I would stay with 5W30. If you do 4-5k OCI, then any conventional oil will be good, if you like to do 7-8k OCI then synthetic oil like Ultra, M1 ... is needed.

 

[hate2work]

Originally Posted By: dtt004
Hi.

It is next to impossible for you to know when Mobil will change their additives. Since the base stocks of today's lubricants are so similar, additive packages serve to differentiate the brands and thus are closely guarded. The only way to see how additives have changed is to compare an oil analysis with another oil analysis and examine the changes.

I don't have a clue why other sites' members are saying to hold off on Mobil 1. Mobil 1 comes as the original factory fill from Porsche, just like Ferrari comes factory filled with Shell/Pennzoil. Although it could be due to contracts and or technical partnerships, Porsche should have great confidence in that oil if they recommend it.

In my opinion, Mobil 1 is a great choice and you should stick with it. Likewise, Pennzoil Ultra is also a great choice and you could stick with that. I doubt you will feel or notice the difference; both oils are well engineered and will last inside any engine.

Turbocharged engines are hard on oil because the oil is used to lubricate the bearings in the turbocharger itself. Unlike a supercharger, which almost always uses a dedicated oil, a turbocharger draws oil from the engine pan. That's why it is important to maintain good driving habits with a turbocharged engine.

The most important thing you can do for your turbocharged engine, and to make it and its oil last longer, is to idle the engine before shutting it down. Or you can use a turbo timer which does it for you. Since the turbocharger takes time for it to stop its 30,000+ rpm rotation, oil needs to be freshly supplied to cool it down. It also will extend the life of your engine oil.

A synthetic oil as you know offers advantages such as extreme temperature shear stability and low temperature ease of starting. They are also engineered in the lab, which enables the addition of a higher amount of additives. Conventional oils of today are approaching the performance of synthetics, but if synthetic is what the owner's manual says, I would recommend it.

The only turbocharged engine I own is in my 1991 MR2. It has a pretty basic setup as far as turbocharged and engine technology go, but I still follow the same deal about idling. It prevents oil coking in the bearings of the turbocharger and extends engine oil life. I use conventional oil, because I believe it is up to the task.

So. As long as the engine oil is of the correct viscosity and carries the correct specifications, it is good to go. You can use Mobil 1 with confidence, as Pennzoil Ultra too.


Great post

 

[r34dy2fly]

Regarding the Mobil1 0W40, when they started doing VOA on it recently, it lacked the Zinc and Phosphorus that it used to have to preserve the engine or so I've read and everyone started moving over to the 5W40 TDT oil. I just went and saw the VOA for the Pennzoil Ultra 5W40 depending on how the oil holds up, I might be moving back to Mobil1.

Regarding the cool-down phase, I generally drive without boost for the last 5-10 mins of my drive to let the turbos cool down. Literally... With no boost and cool air, it shouldn't need to cool down anymore than it did driving back. I understand what you're saying though and good advice.

 

[d00df00d]

to BITOG!


For the Porsche, you should know that Porsche approval is one of the most important for Mobil 1 0w-40, and Mobil's engineers work closely with Porsche to ensure that the oil and the engines continue to be matched. There is a LOT more to its ability to protect the engine than zinc and phosphorus, and most of it will not show up on a standard UOA. I wouldn't switch away from it just because of a drop in the levels of those two additives, especially since the recent reformulation seems to be significantly more advanced (higher viscosity index and HTHS viscosity, etc.). Least of all would I switch to a non-approved oil without EXTENSIVE oil analysis -- and not the cheap $20 kind from Blackstone (figure on at least $60 a shot, preferably more).

I'm not surprised people are switching to TDT. I'm not impressed, either. I don't know what makes people think an oil for trucks is going to be better than an oil for >100 hp/L sports cars that is often used straight from the bottle by race teams. However, it is quite common to believe that low levels of ZDDP (zinc and phosphorus) or the fact that an oil is for cars automatically makes it inferior to anything labeled for use in trucks. Don't buy it unless you're spending the time and money (again, at least an extra $60 per oil change, preferably more) to find out for yourself.


For the Subaru, look in your owner's manual for the specs your car needs, and pick anything that meets them. Literally, anything (although you should make sure you look for explicit approvals rather than vague "meets or exceeds" language). I suspect Pennzoil Ultra in the right viscosity will be one of the best choices on the shelf.

Good luck!

 

[sicko]

Th Subaru will run on anything. If you wanted to save some cash use conventional, the Subaru engines are easy on oil. If you wanted convenience, then use the same oil as you use in the Porsche; the Subaru won't mind a 40wt. Personally I've had non-turbo Subarus for over 10 years. I've mostly used conventional 5w-30 during that time, I haven't been gentle to them and I've never had an oil related issue.

As for the porsche, use what you're confident in, but I'd personally have no issue with using M1. Even with an additive change, I have no doubt that it's protecting the engine fine.

Just my 2 cents on the matter

 

[r34dy2fly]

Appreciate the great advice. I guess I'll look into it more. Especially since my storage shed out back is just stocked with oil.

I went ahead and ordered 2 oil changes worth of Pennzoil Ultra and still have left overs from my Mobil1. When I get back from Georgia with the Porsche, I'll have to send in a UOA to see how the Oil is holding up after 3000 miles of use. This will also allow me to hopefully flush out the quart of the Mobil 1 that was left in the sump.

But 40wt is okay in the Subie? I would be very convenient if I could indeed use the same oils.

 

[bluesubie]

Originally Posted By: r34dy2fly

But 40wt is okay in the Subie? I would be very convenient if I could indeed use the same oils.

Yes. The manual allows a variety of grades (including 50 grades in severe conditions) and yours probably mentions 10W-40 or maybe 5W-40. I forget when they switched to 5W-40. Lots of folks run 40 grades in n/a Subaru's (even Rotella and M1 TDT), but as mentioned, they're very easy on oil and you shouldn't have a problem going to 7,500 miles on synthetic.

I run Pennzoil High Mileage 5W-30 in my 105k mile 2000 Impreza RS at 5-6k mile intervals.

-Dennis

 

[r34dy2fly]

Well I bought cases of Pennzoil Ultra 5w40 Euro for the other car as I planned on running it in the car for a while, so if its acceptable I might just put that in there. I guess we'll see.

I don't know if its because of a sale or not but they're selling Mobil1 0W40 at the PX here for $6.50 (no tax) a quart and I'm tempted but....