Do Full Syn Oils Reduce Sludge & Varnish VS Dino

[1993_VG30E_GXE]

Curious if Synthetic oil has some benefit in this area.

My question would apply to 2 identical brand new motors. Both run in the exact same manner up to 300,000KM. Would the synthetic motor have less sludge or varnish buildup than the one that ran dino it's entire life?

 

[bepperb]

It would depend on the OCI. At 2000 mile OCI there probably would be no difference. At 20,000 mile OCI it would be pretty significant.

Also, does the engine have any very high temp surfaces, like a turbo?

 

[ZZman]

What conditions are they run in? What OCI Intervals? What engines?

Hard question to answer without alot of info.

 

[FrankN4]

Sludge is the breakdown product of oil that has been over-stressed.

Oil can be over-stressed by contaminants and oxidation, or by being run longer than it was designed(OCI). It will break down into a gel that sticks to your engine parts. As the sludge sticks, there is less good oil to circulate and do its protective job. This coating of gel also stores heat instead of releasing it which stresses the radiator and cooling system, which over-stresses the oil, which causes sludge. Just all around bad.

If the OCI is to long, if the engine runs hot, it will oxidize and will leave deposits behind. If the OCI is to long, it will not hold blow-by contamination in suspension and the result is sludge.

A GP IV oil can be run to long between OCI, and be stressed. It will, however hold up better than a GP III, which will hold up better than a GP II.

 

[ZZman]

I do believe if you look at Syn Engines as a whole they are very clean. Does that equate necessarily to longer life? Hard to say as most people never run their cars long enough to find out.

Also sludge is rare unless the car is abused or has mechanical issues. Varnish is usually a minor cosmetic issue.

 

[bepperb]

" Varnish is usually a minor cosmetic issue."

I agree, but I'm starting to see a pattern where every picture I see of an engine getting it's valve guide seals getting replaced also has a lot of varnish. May be just a coincidence, or two symptoms of the same neglect.

 

[tig1]

M1 will clean up the sludge left behind by dino.

 

[1993_VG30E_GXE]

Is this varnish normal though guys? I'm doing the teardown we spoke about earlier, and this motor has about 400-500K km on it. Reason I asked the original question, is, I wonder if it's worth it to start it on SYN after the break-in period, once my overhaul is complete.

 

[1993_VG30E_GXE]

 

[1993_VG30E_GXE]

This VG30E motor had dino it's whole life, and this is the first opening of it.

 

[aquariuscsm]

Looks like a bit of sludge.

 

[aquariuscsm]

What kind`ve Nissan did this engine come from? Looks like a Z31 engine.

 

[1993_VG30E_GXE]

Came from a 93 Maxima

 

[7777]

For dino, thats not to bad, Ive seen a lot worse.I would definitely go with synthetic after break in.

 

[Carzzz]

my VG30 doesn't have that much of varish/sludge...

 

[ARCOgraphite]

Oils with at least a 20-30% group V in the blend should not sludge - but may clean up faster than you want ... Most of these are the ultra premium Euro synthetics.

 

[ZZman]

No that is not normal.

 

[Steve S]

That is not enough sludge to worry about. Sludge only hurts when there is enough to clog the pickup screen to the oil pump.

 

[Gary Allan]

Originally Posted By: 1993_VG30E_GXE
Came from a 93 Maxima/ Is this varnish normal though guys?



I would term it "not atypical" for an engine of that mileage (kilometerage

)

It's 16 mo old. Lots of varied usage with lots of older oils. Probably if you had the same engine today, with today's oils over reasonable OCI's ..it probably would look much better.

Most cars do not have a flat usage profile for their entire lives. Most get retired to a lesser service and get less premier maintenance. Even if they do get good maintenance, the service tends to move from ideal to marginal (short trips, or winter duty only).

 

[SLCraig]

Originally Posted By: 1993_VG30E_GXE
This VG30E motor had dino it's whole life, and this is the first opening of it.


I think Nissan makes the best engines on earth, that's no surprise it looks that good!

(I'm a Nissan Fanboy who can't afford the Nissan he wants)