5w40 vs 10w60 oil?
5w40 vs 10w60 oil?
Author
Discussion

G-996

Original Poster:

163 posts

141 months

Sunday 19th March 2017
quotequote all
For a 2003 996.2 Carerra 4 with 69k miles, which viscosity engine oil would people recommend?

I've had the car for 3 years and in that time it has run on 5w-40 oil (Valvoline). It has just had a cylinder head gasket leak repaired which involved taking the engine out and skimming the head. When I picked the car back up from the Porsche Indy dealer they told me they were recommending 10w60, as this will stand up to higher temperature running better.

In terms of driving cycles, the car does approx 4K miles per year, generally long journeys, and always warmed up properly before giving it the beans.

And advice gratefully received!

tr7v8

7,617 posts

256 months

Sunday 19th March 2017
quotequote all
Hartech only warrant their rebuilt engines if run on Millers 10w/60 There is also a lot of stuff written in the US about heavier oil being better in M96/7 engines. I ran mine in the Boxster at 80K miles with 5W/50 Comma Motorsport & it ran & sounded better.

skinny

5,269 posts

263 months

Sunday 19th March 2017
quotequote all
10w-60 is quite extreme for normal road use.

10w-50 might be a better bet

G-996

Original Poster:

163 posts

141 months

Sunday 19th March 2017
quotequote all
skinny said:
10w-60 is quite extreme for normal road use.

10w-50 might be a better bet
When you say extreme for road use, could you help me understand what issues it might cause? Thanks

MMT

598 posts

214 months

Sunday 19th March 2017
quotequote all
tr7v8 said:
Hartech only warrant their rebuilt engines if run on Millers 10w/60 There is also a lot of stuff written in the US about heavier oil being better in M96/7 engines. I ran mine in the Boxster at 80K miles with 5W/50 Comma Motorsport & it ran & sounded better.
Hartech recommend Millers 10w50 nanodrive cfs nt.

https://www.hartech.org/rebuild-terms

tr7v8

7,617 posts

256 months

Monday 20th March 2017
quotequote all
MMT said:
tr7v8 said:
Hartech only warrant their rebuilt engines if run on Millers 10w/60 There is also a lot of stuff written in the US about heavier oil being better in M96/7 engines. I ran mine in the Boxster at 80K miles with 5W/50 Comma Motorsport & it ran & sounded better.
Hartech recommend Millers 10w50 nanodrive cfs nt.

https://www.hartech.org/rebuild-terms
Don't rely on my memory especially with the amount of painkillers I am on.

Wombat3

14,928 posts

234 months

Monday 20th March 2017
quotequote all
G-996 said:
skinny said:
10w-60 is quite extreme for normal road use.

10w-50 might be a better bet
When you say extreme for road use, could you help me understand what issues it might cause? Thanks
The two numbers in an oil grade refer to firstly the viscosity when cold (so 0W40 is thinner at cold that 10W40) and then the second number relates to the operating temperature range - or (as I understand it) the temperature at which the oil will get to operating viscosity.

So if you run 10W60 in an engine that only needs 10W40 its going to be too thick at that engine's normal operating temperature, it needs higher temperatures to thin down to normal operating viscosity. That might then result in reduced oil flow (and higher oil pressure) which may then "test" some seals.

mmcd87

632 posts

231 months

Monday 20th March 2017
quotequote all
My 996 is running Millers NANODRIVE CFS 10w-50 NT as per Hartech recommendation. Worth giving them a call for advice. There is probably a few options at your mileage.

mm450exc

571 posts

206 months

Monday 20th March 2017
quotequote all
0W-40 is default from Porsche. 10W-40 will be ok. 10W-60 for heavy track use. I use it in the GT3.

boxsey

3,579 posts

238 months

Tuesday 21st March 2017
quotequote all
My old 964 didn't get on well with 10W60. There was a noticeable dulling in the performance. Even when used on track where the oil should have got hot enough. Have a read of this:

http://www.opieoils.co.uk/pdfs/tech-articles/10w-6...

The symptoms they describe of an oil being too thick are what I experienced when using it. Yet, Porsche recommend its use for the air cooled engines (their classic oil)!

Rockster

1,515 posts

188 months

Tuesday 21st March 2017
quotequote all
G-996 said:
For a 2003 996.2 Carerra 4 with 69k miles, which viscosity engine oil would people recommend?

I've had the car for 3 years and in that time it has run on 5w-40 oil (Valvoline). It has just had a cylinder head gasket leak repaired which involved taking the engine out and skimming the head. When I picked the car back up from the Porsche Indy dealer they told me they were recommending 10w60, as this will stand up to higher temperature running better.

In terms of driving cycles, the car does approx 4K miles per year, generally long journeys, and always warmed up properly before giving it the beans.

And advice gratefully received!
If the engine made it to 69K miles with Valvoline 5w-40 oil and the engine is not manifesting issues attributable to the oil why change oils now?

BTW, 10w-60 is *not* a Porsche approved oil so if anybody recommends that oil they are recommending an oil that Porsche doesn't support in its engines. I know the tendency is to ignore what Porsche has to say on this matter and listen to almost anyone else. I know this isn't what people like to hear but Porsche is the only real authority on the oil for its engines.

'course, if you decide to ignore what Porsche has to say on this subject and listen to someone else you can pick an oil using any criteria you want. Viscosity. Price. Pretty bottle. Taste. Anything.

My advice would be to stay with the Valvoline 5w-40 oil and change it every 5K miles or once year if you don't put 5K miles on the car. I offer this without first confirming the Valvoline oil is on the approved list. If it isn't there are a number of 5w-40 oils that are.

Be aware if you live/drive where it gets cold, -25C or colder, Porsche says to use 0w-40 oil.

(As an aside my 2002 Boxster engine is up to 310K miles and has managed to cover most of those miles with 0w-40 oil. Only in the last year or two did I switch over to 5w-50 (not a typo for 15w-50!) oil mainly because while it doesn't get that cold where I live and drive it gets pretty hot, up on the triple digits. Likewise my 2003 Turbo is now up to 152K miles and mostly on 0w-40 oil but at the same time I as switched the Boxster over to 5w-50 oil I switched the Turbo over to using 5w-50. Both engines get 5K mile oil/filter services.)

G-996

Original Poster:

163 posts

141 months

Sunday 26th March 2017
quotequote all
Quick update - I had a chat with Hartech and will be changing to Millers 10w50 nanodrive cfs nt. The rationale for going to this viscosity is that as engines wear, tolerances widen, so a slightly thicker oil than original OEM spec helps reduce wear. The Millers oil also has some specific benefits.

Thanks all for the advice and views!