Ultimate Motor Oil Thread or Why we hate CJ4/SM oils

[941MXVET]

Well we just closed a deal this morning on a '91 911. In doing our DD on the purchase, we found this thread to be very eye opening and informative. (Thanks to all for sharing their knowledge) We are planning on using Swepco in the 911 as many have suggested on this thread. My question is this: If I'm using the Swepco in the 911, would there be a significant bennefit in using it also in our '98 2.5l Boxster? I'd like to us the best possible oil in both cars, and haven't found as much info on the water cooled engines. Thanks in advance.

[cnavarro]

I'm very close to recommending Swepco 306 15w40 for pre-variocam+ engines, since they are not so sensitive to viscosity increases.

I've been running a 50/50 blend of Brad Penn 20w50 and 0w30 (net 10w40) in my '99 2.5 Boxster with excellent results (even cold starts below 0F with our spin-on oil filter adapter), but after getting back our bearing analysis from the intermediate shafts, I'm starting to think an oil formulated with moly is needed and will improve longevity of the IMS. There are quite a few oils that fall in that category, but Royal Purple and Swepco as far as I know have the highest levels of moly-based friction modifiers/extreme pressure additives.

At the bare minimum, using Swepco's oil improver 502 is probably worth adding to any factory approved fill & viscosities (even on Variocam+ engines) at the bare minimum to up the extreme pressure additive levels.

[wswilburn]

Charles,

It would be interesting to hear your recommendation for viscosity vs. ambient temperature for the air cooled engines.

[cnavarro]

I go by the Porsche manual, say from a mid 90's 911 - 20w50 down to about 15-20F, then 15w40 down to about 5-10F, then a 10w40 under 0F roughly - I can't remember the exact #s, but I have a picture of the page from the manual somewhere on my website. You really don't need a 5w40 or 0w40 until you're in the artic!

Likewise, ambient air temps under 90F, 15w40 is ok - above 90F, then really you should use a 20w50.

[old man neri]

Originally Posted by cnavarro

I go by the Porsche manual, say from a mid 90's 911 - 20w50 down to about 15-20F, then 15w40 down to about 5-10F, then a 10w40 under 0F roughly - I can't remember the exact #s, but I have a picture of the page from the manual somewhere on my website. You really don't need a 5w40 or 0w40 until you're in the artic!

You would be surprised what oil looks like in really cold temperatures. I use 5W40 and I still won't start it under 0F unless I really have to. I got the spare quart out of my car when it was -40F just to see what it looked like. I could take the cap off, turn the quart up side down, and nothing came out for a few seconds. It was like molasses but thicker.

I really need to figure out how to get some sort of block heater in that car.


I actually use 5W40 all year round. I hope that isn't detrimental in the summer time. Your thoughts?

[941MXVET]

Originally Posted by cnavarro

I'm very close to recommending Swepco 306 15w40 for pre-variocam+ engines, since they are not so sensitive to viscosity increases.

I've been running a 50/50 blend of Brad Penn 20w50 and 0w30 (net 10w40) in my '99 2.5 Boxster with excellent results (even cold starts below 0F with our spin-on oil filter adapter), but after getting back our bearing analysis from the intermediate shafts, I'm starting to think an oil formulated with moly is needed and will improve longevity of the IMS. There are quite a few oils that fall in that category, but Royal Purple and Swepco as far as I know have the highest levels of moly-based friction modifiers/extreme pressure additives.

At the bare minimum, using Swepco's oil improver 502 is probably worth adding to any factory approved fill & viscosities (even on Variocam+ engines) at the bare minimum to up the extreme pressure additive levels.

Thanks for your reply. It looks as if the choise is an easy one. I'm just not hearing anything bad about Swepco, and BP oils. With your "almost" recomendation, I'll be adding Swepco on our next change.

[darkbeer]

This IS a great thread, with, perhaps, some of the most important info. needed for 65-98 aircooled motors.
....the problem is that it is so long & spread out, that I'm not sure where my question may have already been asked/answered....
I am thinking that Brad Penn (old Kendall people??) & Swepco are both safe bets for both my 3.2 Carrera motor & my lovable but seldom respected 912E motor...

Am I correct ?????

[Porsche_monkey]

Originally Posted by darkbeer

I am thinking that Brad Penn (old Kendall people??) & Swepco are both safe bets for both my 3.2 Carrera motor & my lovable but seldom respected 912E motor...

Am I correct ?????

Yes, I think so.

[HarryD]

Added Cliff notes version on Page 1

[egertk]

Any thoughts on 7th Gear motorcycle oils?
http://www.7thgear.net/7thGear/Default.aspx?tabid=39
They list having a high ZDDP content, and it comes in a synthetic blend 20W50 on amazon for 67 bucks for 4 gallons. Any thoughts?

[cnavarro]

Looks promising, but one has to consider our evaluation of oils (more than just Zn and P levels alone) has been going on since early 2005. It has taken many engine builders years to physically verify that these oils are indeed performing up to their expectations like with the Swepco and Brad Penn.

I'm sure there are plenty of other oils out there that might be just as good, but one needs to follow up when using these products with used oil analysis and ideally, in conditions where teardowns are frequently done, like on a race engine. There's nothing like the punishment of racing to ensure your lubricant is up to the task.

[356robo]

I'm looking for advice on change interval. I'm using Mobil V-Twin. Oil has been in the engine for 12 months with only 2,200 miles. Do I need to change it?

Thanks in advance,

Rob

[carnutzzz]

Originally Posted by 356robo

I'm looking for advice on change interval. I'm using Mobil V-Twin. Oil has been in the engine for 12 months with only 2,200 miles. Do I need to change it?

Thanks in advance,

Rob

Yes.

[NathanUK]

I posted a question here:
An Oil Additive that is worth using

[WERK I]

Originally Posted by 356robo

I'm looking for advice on change interval. I'm using Mobil V-Twin. Oil has been in the engine for 12 months with only 2,200 miles. Do I need to change it?

Thanks in advance,

Rob

Yes. The effective life cycle of engine oil is not only mileage usage, but also time. Generally, the 6-month and/or mileage rule-of-thumb applies.

[RWebb]

I have never heard of a "6-month" rule of thumb.

I often see instructions to change the oil every 1 year, no matter what the mileage.

[WERK I]

Originally Posted by RWebb

I have never heard of a "6-month" rule of thumb.

I often see instructions to change the oil every 1 year, no matter what the mileage.

Really? I heard of the coolant change "1 year", but not oil.

[afterburn 549]

Just found this on the shelf..Might help in the Zinc dept ?
A product of Lucas..says use for break in and add to every oil change

[brads911sc]

Just use a good oil... additives are mostly hype... and the oil passages in your p car engine may not like it...

[afterburn 549]

Yea but good oil ..they put zinc in ...So doing it after would seem OK