Ufnavy06

I'm inching closer to an oil change as it's been a year and about 1500 or so miles.

What oil do you use in your 968?

DSMblue

I'm running Mobil 1 0w-40

Yogii

I'm thinking about changing from Mobil 1 to this:
https://lnengineering.com/driven-dt5...28-models.html

-Yogii
AKA 968 Novice

chudson

Navy - these type of questions generally start a firestorm of answers. My opinion is that any top quality oil is good if you have picked a lubricant with the proper specifications and correct additives for your car. I would not be pouring the 0 viscosity oil in any of my 968s as was previously mentioned by another poster. Not picking a fight - just my opinion.

I personally use Driven full synthetic 15w50 (bottle is labeled DT50) which is actually an oil blended by them for air cooled Porsches, but picked personally for the 968 engine by Lake Speed Jr when he was at the helm of Driven (we have a mutual friend). Lake grew up in a racing family and if you will watch some of his videos where he discusses lubricants and how the small things make a big difference, you will be blown away with his knowledge. DT50 is also blended with higher amounts of the stuff that old school high-performance engines like. Again, there are a lot of lubricants that will be fine and will do no damage to your engine, but do your research because it's not just "a bottle of oil". I hope this helps.

https://drivenracingoil.com/i-304977...mance-oil.html

Ufnavy06

Definitely not looking to start any firestorm. Just figured I'd get a read on what folks are using.

I understand there may be some discussions, but that's all they need to be.

chudson

"Firestorm" was probably a poor choice of language, but heated arguments regarding similar subjects have been known to happen in the past and I've even seen people banned over them. A lot of lubricants are good which is why I started my response with "any good top quality oil". Sorry to suggest that we had a fight coming. Should have said "There will likely be many different opinions here".

Cliff

Yogii

My limited understanding is that 968 need some zinc in it's oil. Many new synthetics do not have this.
More knowledgeable people please chime in.

-Yogii
AKA 968 Novice

chudson

There are no doubt plenty of lubrication specialist on the globe. If you would like to watch some interesting videos with a certified lubrication specialist who's depth of knowledge amazes me, youtube "Lake Speed Jr oil". You probably want to settle in and get comfortable because these aren't 5 minute videos. Lake is now with a piston ring company, but these videos as still a wealth of knowledge.

Yes, lubricants today are targeted with friction reduction in mind as well as being friendly to the catalytic converter. I don't want a water thin oil and since our cars have what I believe to be "robust" old school catalyst, I'm not concerned about one getting damaged by the zinc content. I actually don't know if I've every read a post where someone stated that their car failed an emission test because of catalyst efficiency.

Bear in mind that I have no affiliation nor anything to gain - I don't get a penny to endorse any product. But I've met Driven's owner Joe Gibbs and he was not only very approachable but very kind and accommodating and doesn't blow you off like a lot of people in his position tend to do. I was also very surprised when Lake was willing to review the needs of a 968 engine and make a personal recommendation as to a lubricant. As stated in a previous post, any top quality brand meeting the lubrication specifications for our engines will be just fine, but I do prefer a lubricant with the additives that an expert felt was a benefit to our old school engines.

Cliff

Yogii

Cliff,

Like I said, I leaning toward using them at my next oil change. I recently received a notice, and it is not that expensive.

-Yogii

gtolou

Kinda the way I think too. I like the VR-1 valvoline. Racing. 20-50. Higher levels of zinc. Decent price. I've got a couple of old muscle cars, I run the 10-30 in them.

dbonds

One item to add on this topic - a couple of oil changes back, I had my mechanic do the oil change as my 968 was in there for other work. They used 5w-40 oil (which IS within specs per the manual). This was in April of '21 and it was HOT outside - upper 90s F. I noticed (on a couple of occasions) that my idle oil pressure when the car was hot and it was hot outside got lower than I was comfortable with - my digital aftermarket oil pressure gauge showed ~19psi at idle a couple of times. It never triggered the oil light in the dash, but I switched oil again a few months later with 20w-50 (what I normally use - LiquiMoly) and idle oil pressure stayed higher (>26psi at idle) at same weather temps. Since I live in a relatively hot climate, I'm staying with the heavier weight/higher viscosity oil (20w-50) to ensure I have decent pressure at idle.

Yogii

Once again, my limited knowledge can be a problem....

I understand that our 968's need high oil pressure to ensure that ______________?
Is it that one of the oil journals is undersized and the pressure is needed to provide oil to the back of the cylinder head??? Is this right?

-Yogii
AKA 968 Novice

walfreyydo

Valvoline VR1 20W-50 is the go-to for warm weather. It has the zinc and it has the proper viscosity as outlined in the owners manual for the temperature range. I wouldnt run this in the winter below temps of 20F though. For that you might want to go to a 10W-30 or something.

chudson

The Valvoline mentioned is good juice. I would have much preferred a 20w50 for my cars and IIRC, there is a 20w60 racing juice that someone offers. I’ve heard that recommended for full race applications. But I’ve busted the bearings out of my track car which regularly sees 7000 + and they were so good on the Driven 15w50 that I could have reinstalled them.

Yogii - it’s not a clearance issue, but rather an issue where the design of our lubrication systems tends to starve rod bearing # 2 and 3 when at high RPM in high speed corners (if I’m remembering correctly…). Search - there is plenty to read on the subject. Someone driving a street car has nothing to be concerned about. And as to your question concerning oil pressure, more pressure = better lubrication.

Cliff

Yogii

Great news. Seems we have some good choices.

Like I mentioned I'm thinking of changing from Mobil 1 when I take my car out of hibernation next month.
Still not sure if it will be Valvoline VR1 20W-50 or Driven DT 50 15-50.
Will the Valvoline have any effect on my Catalytic Converter? I do need to pass Cali smog.

-Yogii
AKA 968 Novice