jcb-memphis

I like 5w-50...been using it for 1 year now. Less oil consumption too...about 0.2 q per 1k mi.....

Just a data point.


Jeff

cgng30

ltc i just got the 5w-50 oil from avlube and i notice that it does not say rally formula , not porsche a40, it says supersyn tech and porsche approved list 2002. do i have a different version , or is the same?

thanks ronnie

Blackness

I know this is probably futile asking this, but did anyone make a note of the oil temps before and after running the 5W50?

Joe Weinstein

Viscosity is liquid friction, so under controlled conditions, increasing viscosity means oil temps should rise.

Mikelly

Just ordered 5 cases of 5W50 as well... $235 for essentially 3 oil changes...

Mike

Blackness

I realize it's a complex issue, but wasn't sure if there would be a different heat capacity between the two and you might actually see lower temps. I've read those claims before, but haven't seen any hard data to back it up.

Kevin

Blackness, for a NA car I wouldn't worry about the change. However, in a turbo with the higher heat coming/generated from the oil cooled turbochargers and the oil squirters, it does merit moving up to a 5W50.

If you are happy with 0W40 run it.

Joe Weinstein

If viscosity of the base oil is linear with density (it may not be), then a heavier oil might have
marginally higher heat capacity, but oil viscosity at working temperatures is controlled more
by the polymer additives, so the actual density might not be much different. And even at that,
the amount of heat imparted to the oil is a function of it's length of contact with the heat source,
and because higher viscosity oil delivers less flow than a thinner oil for a given pressure, it is
likely to leave bearings at a hotter temperature than a thinner, higher-flowing oil. And note
again, that viscosity is liquid friction, so thicker oil is going to get hotter being squeezed through
a tight gap than thin oil, even with no external heat applied. Lastly, heat is bad for oil, and
oil degrades with high temperature, about the same temperatures degrade all oils regardless
of viscosity, so over time, thick oil's internal heat generation contributes more to it's own demise.

Kevin

Joe, I hope for my sake that you would upgrade to a 5W50 at some point for your turbochargers benefit. The K16 or K24 turbocharger had very little "bearing" problems running the 20W50 in the 993TT. We are seing more thrust bearing wear with the 996TT platform. With that said, we are extracting more power and seeing higher shaft speeds with the turbochargers on the 996TT platform.

wross996tt

I switched with my last oil change...so far so good.

PAULUNM

Kevin,

What are your thoughts on Mobil 1 5w50 being a SM spec oil (same as M1 0w40)?

Would a SL spec oil like Motul 8100 X-Cess 5w40 make more sense- since we tend to believe the SL spec oils have a higher ZDDP content than the SM- and therefore have greater wear protection?

Kevin

Paul, if you are worried about the ZDDP content then run Mobil 1 Diesel/Truck 5W40 It's more readily available and it has more ZDDP in it. I can't remember but I think it's 200 to 300 ppm more. However, this isn't a approved oil. Would that stop me >> No..

Interesting that over the years I receive PM's and emails asking me what "I" use..

I have my test engines on Motul 300V

My 996TT on Mobil 5W50..

My aircooled turbo engines are "all" running Mobil VTwin oil.

My brothers 996TT is running Mobil Diesel/Truck 5W40 (he can pick it up everywhere)

My Escalade is running Mobile Diesel Truck 5W40

My Dodge Pickup is running Mobil Diesel Truck 5W40

My Motorhome with a 515HP 12.7ltr is running Mobil Delvac 15W40

PAULUNM

Thanks Kevin. I don't really have the expertise to worry about ZDDP levels in M1 5w50. It is telling that you run 5w50 in your turbo.

Do you have any customers using Shell Rotella T 5w40 in their 996tts?

Do you personally think that the added ZDDP in the diesel oils can really prevent wear in our applications?

This is such a complicated subject- good to hear your opinion on the matter.

Kevin

Paul you are in LA.. I'd be more concerned about the benifits of the 50 weight vs 40.. Thermal breakdown is worse than "less" additives. Shell is a great oil, but I run Mobil.

Oil is like the lifetime debate, battle >> Ford vs Chevy, Blonde vs Brunette... It will never end. With that said, I will remove a Shell product and run the Mobil product.

PAULUNM

Well said. I'll stick with my 5w50! Thanks for your input!

Now, I plan to run a 5k interval- but I'm tempted to go with 3k (I'm **** like that)... Thoughts?