been away for a while, switched to synthetic since

[19jacobob93]

Hello all! I've been away for a few months because I moved house, my PC is packed away and I have a new phone...
Anyway, I've made the switch to fully synthetic since then!
I ran Penrite HPR10 10W50 from 220-230k, then the last change I used the same oil but in a thinner 10w40, the car is currently at 232k.
I had the big initial burnoff many people experience when switching to syn (someone explain this haha) it used 1 liter/quart in the 1st week and then not a single drop for the next 10k!
The synthetic oil I'm using now says it's non friction modified, what does this mean exactly? I know the Durablend I was using before the switch did contain friction modifiers. What are they and how do they work?

 

[dlundblad]

I always thought friction modifiers were used for diff fluid and ATF.

Perhaps the previous synthetic you were using could have been used in a shared sump on a motorcycle as well as serving as engine oil for a passenger car?

 

[Garak]

Check some of Mola's posts. I can't recall where, but there was a big thread on friction modification. Basically, the goal is, big surprise, to reduce friction, often in an attempt to improve fuel economy (and reduce power loss). Moly is but one example. Applications with shared sumps do better without friction modifiers, so motorcycle oils will often lack friction modifiers, and advertising a PCMO as non-friction modified may be a good bit of marketing to attract the motorcycle crowd, assuming the viscosity is within reasonable range (i.e. not a North American 0w-20).

 

[B320i]

For whatever reason, I had reason to look up your UOA from a while back and wondered where you had been.

Did you ever get that knocking/slapping sound sorted in the Falcon, or is it still present?

The Penrite 10w50 seems like a nice oil. Just did a UOA myself on it after about 5500km (still in use) on the Bimmer. Based on the viscosity Blackstone noted, it was nearly a 60-weight oil NOW (16.1cSt), although Penrite advertises the stuff as being 18.1 when new.
Now I can lie and say I've got M5 "bearing protection" oil in my car!

 

[19jacobob93]

All Penrite oils are high in zinc, wouldn't that be classed as a friction modifier though? I thought it's properties were similar to moly

Oh haha so I've been missed?
And that knocking went away after switching to Penrite and even when switching back to thinner stuff it hasn't been present... only did it with 10w30 which adds to the mystery! I know its not worn bearings or anything anyway.
Wow that's crazy! I didn't think it was that thick! I didn't notice anything in the way of a drop in economy or anything though!

 

[Kira]

Welcome back (though I'm not an official welcome backer).

Your one week conv. to synth. adjustment period is notable. Kira

 

[virginoil]

Originally Posted By: Kira
Welcome back (though I'm not an official welcome backer).

Kira


Please let me know whom the official BITOGoers anointed as the official welcome backers are.

 

[Garak]

Originally Posted By: 19jacobob93
All Penrite oils are high in zinc, wouldn't that be classed as a friction modifier though? I thought it's properties were similar to moly

No, anti-wear and friction modification are different principles. Moly is, however, an anti-wear compound if you dose it high enough. And no, it's always hard to measure fuel economy differences. They're there, but we can't measure them outside a lab.