Timing chain & oil

[Camprunner]

Is there any evidence that a higher viscosity oil 30,40 weight creates less timing chain wear then say running a 20 weight oil?

 

[Vern_in_IL]

it could be more oil flow would make the difference

 

[SatinSilver]

Using cheap, inferior generic oil may cause issues. And letting the oil go too long before changing seems to cause the most issues.

What oil is called for in the 2012 Pathfinder if that's the vehicle you're inquiring about?

 

[OneEyeJack]

I do not know about timing chains in automobiles but in a couple of vintage motorcycles I've had that use a chain from the engine to the gear box that's immersed in oil the wear reduction on the gears and chain I experienced going from a 40 to a 60 weight oil was dramatic.

I have no idea if that translates to a modern automobile but if I had a chain drive camshaft(s) I'd at least do a used oil analysis every now and then to see if the chain was starting to throw off wear particles.

The problem I've seen with chain drive camshafts is the guides, tension devices and dampers, not the chain itself.

Years ago I use to buy 510 Datsuns, fix them up and resale them, especially the wagons. The chains were never a problem but that one guide was.

 

[Camprunner]

Originally Posted By: SatinSilver
Using cheap, inferior generic oil may cause issues. And letting the oil go too long before changing seems to cause the most issues.

What oil is called for in the 2012 Pathfinder if that's the vehicle you're inquiring about?


The 2012 calls for a 5w30 although the same motor in the early years of production had a much wider range of oils that could be used depending on tempeture. (VQ40DE V6) there are some reports that running a 0 or 5w40 synthetic makes the timing chain guides hold up longer but it seems to be subjective?

 

[Nate1979]

Clean oil might be more important. Here is one article by Lubrizol on the addition of new tests for GF-6:
http://www.gf-6.com/ilsac-timing-chain-wear-test-gf-6-specification

It's been posted on here before.

 

[expat]

The only story I can contribute to this is:

I was once working on a Toyota 22 R that had a stretched timing chain. The engine was known to have had poor maintenance (infrequent OCI's with cheap 10w30)

While removing the chain I found the cam very stiff to turn, like it would stick, and require a lot of effort to get it to turn, but would then un-stick and move freely.

The cam was removed, and the cam and bearings cleaned of varnish. After which, the cam moved freely.

I think a lot of the chain stretch was due to the cam sticking.

 

[tig1]

Originally Posted By: Nate1979
Clean oil might be more important. Here is one article by Lubrizol on the addition of new tests for GF-6:
http://www.gf-6.com/ilsac-timing-chain-wear-test-gf-6-specification

It's been posted on here before.


+1.
The most important thing with timing chains is the engine needs to stay varnish and sludge free. Varnish and sludge can restrict the oil flow to the chain guides and and wear them out prematurely. I have been using 0-20 for several years now in both Fords with OHC chains with no sign of chain problems. Also 20 wt. oils will flow quicker in cold temps as well.

 

[Solarent]

In addition to the information about cleanliness and varnish removal there is also this

Quote:
The timing chain is constantly facing unfavorable mixed and boundary layer lubrication regimes. Mixed and boundary layer lubrication regimes are not the ideal hydrodynamic lubrication regime, where metal surfaces are well separated by a protective oil film. GDI and GDI-T engine field experience shows that, in addition to timing chain wear, more aggressive oxidation, viscosity gains, and related increases in varnish deposits can occur. None of this is good, so improvement in lubricant performance is necessary to enable the successful introduction of this new engine technology.


So the surface active molecules (anti-wear/friction modifiers) are also very important - in addition to their standard function an ability to reduce varnish would be helpful. This is all part of the technology being developed for GF-6.