sludge and dino oil

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beaver land EH?
So long as: (a) your OCI is fairly reasonable (3~5Kmiles for conventional); (b) your PCV valve is working fine; (c) your engine is well in-tune with fresh spark plugs, etc. (d) your thermostat is working properly (e) you are using ILSAC GF-4 certified motor oil, then almost all OTC motor oil, regardless of whether it's a blend or syn, shall not sludge up at all. Sludge is no longer an issue with API SM/ILSAC GF4 graded motor oil, regardless of brand. Q.
 
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Quest - good pts - but he wasn't asking about dino vs. synth . He was asking about viscosity. Perhaps ask it this way - take an engine known to be hard on oil - perhaps one of those VW 1.8T from several years ago - put YB 5w20 dino in one, and YB 20w50 dino in another (8k OCIs) - which engine survives the longest or looks the best at 100k? (rereading the OP, perhaps I missed it too. Perhaps I need to ask my question in a different post - seems interesting (to me))
 
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beaver land EH?
I guess I'd never venture into the areas of "thick" motor oil anymore since the 90s, and been staying with anything 10W30 or lighter weight. Once again, my take is on the specifications and not on any specific viscosities or brands. If a certain gasoline engine grade 10W40/20W50 can pass the ILSAC GF4 spec (which I doubt it, esp. for some 20W50 last I saw on W-M shelves), there's no guarantee on the "cleanliness". Also: for certain car/engine designs such as VW 505.2 spec., Honda HTS-06(sp?), etc. would be desirable if that's what your engine calls for, in addition of ILSAC specification. AGain, my take on the subject. Q.
 
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Any SM or higher rated Dino oil with a reasonable oil change interval of 3K-5K Miles in a properly maintained, mechanically sound engine will not cause sludge. Most sludge issues are due to owners overextending their OCI's not reasonable given their engine design, maintenance record, mechanically soundness, or because of short trips etc. Basically over taxing their oil to the point it can't handle it anymore.
 
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 Originally Posted By: StevieC
Any SM or higher rated Dino oil with a reasonable oil change interval of 3K-5K Miles in a properly maintained, mechanically sound engine will not cause sludge. Most sludge issues are due to owners overextending their OCI's not reasonable given their engine design, maintenance record, mechanically soundness, or because of short trips etc. Basically over taxing their oil to the point it can't handle it anymore.
Agreed. There are some crazy OCIs around here...
 
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ON, Canada eh?
 Originally Posted By: StevieC
Any SM or higher rated Dino oil with a reasonable oil change interval of 3K-5K Miles in a properly maintained, mechanically sound engine will not cause sludge. Most sludge issues are due to owners overextending their OCI's not reasonable given their engine design, maintenance record, mechanically soundness, or because of short trips etc. Basically over taxing their oil to the point it can't handle it anymore.
I should have added: "But lets blame it on the oil being WAX based!"
 

tonycarguy

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 Originally Posted By: Quest
I guess I'd never venture into the areas of "thick" motor oil anymore since the 90s, and been staying with anything 10W30 or lighter weight. Once again, my take is on the specifications and not on any specific viscosities or brands. If a certain gasoline engine grade 10W40/20W50 can pass the ILSAC GF4 spec (which I doubt it, esp. for some 20W50 last I saw on W-M shelves), there's no guarantee on the "cleanliness". Q.
By rule, 15w- and thicker grades cannot be GF4 certified. I also don't think 10w40's can qualify either, even synthetics. So you're implying these weights are more sludge prone (?) What about the GF4 makes it sludge resistant?
 
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The last time I used dino oil was several decades ago when we all used 10-40 dino. Been on synt. ever since. I wouldn't use dino past 5000 miles. Maybe good for more but I wouldn't trust it.
 
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 Originally Posted By: tig1
The last time I used dino oil was several decades ago when we all used 10-40 dino. Been on synt. ever since. I wouldn't use dino past 5000 miles. Maybe good for more but I wouldn't trust it.
In years past, I ran dino oil for over 6k miles, on more than one ocaasion, in a VW 1.8L Turbocharged engine. The oil did not sludge, get gooey thick, or cause any damage as far as I can tell. That was over 100k miles ago, and my VW's little 1.8T still purrs like a kitten. Dino oil is much better than many of us are willing to give it credit for.
 
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 Originally Posted By: wavinwayne
 Originally Posted By: tig1
The last time I used dino oil was several decades ago when we all used 10-40 dino. Been on synt. ever since. I wouldn't use dino past 5000 miles. Maybe good for more but I wouldn't trust it.
In years past, I ran dino oil for over 6k miles, on more than one ocaasion, in a VW 1.8L Turbocharged engine. The oil did not sludge, get gooey thick, or cause any damage as far as I can tell. That was over 100k miles ago, and my VW's little 1.8T still purrs like a kitten. Dino oil is much better than many of us are willing to give it credit for.
I see you keyed off my post. I ment in 1960. Dino oil caused all kinds of sludge then. Many old timers will testify to that.
 
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beaver land EH?
 Originally Posted By: tig1
I ment in 1960. Dino oil caused all kinds of sludge then. Many old timers will testify to that.
Old habits die hard and frankly, those were the days where (up until the late 80s/early 90s where most motor oil was at borderline Gp1) motor oil, even if they passed API specifications, cannot be guaranteed as far as oil oxidation resistance, cleanliness, etc. concerned. Moving forward to ILSAC GF specifications: if you to look at the soon-to-be-coming-to-your-neighbourhood GF-5 specifications, it requires motor oil to not only pass all the industry's standards as far as valvetrain wear, etc. but also oxidation resistance and self-cleanliness, etc. that only modern Gp2+ or blend with other Gp base oil can achieve. GF-4 is also based on this idea but with slightly older requirements that came along during the late 90s/early 00s. Call it anyway you want but I simply cannot see the correlation RE: motor oil serviced some 40yrs ago has to do with modern API SM/ILSAC GF-4 (or soon to be coming GF-5) as far as sludge prone and oxidation-resistance's concern. Again, I just can't stressed enuf that lubricant technologies have come a long way during the past 20yrs, so much so that even the lowly OTC conventional oil sold these days are far superior to that back in the late 80s, letting alone those from yesteryears (60s). Just take your pick and drive happy. Q.
 
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 Originally Posted By: tig1
 Originally Posted By: wavinwayne
 Originally Posted By: tig1
The last time I used dino oil was several decades ago when we all used 10-40 dino. Been on synt. ever since. I wouldn't use dino past 5000 miles. Maybe good for more but I wouldn't trust it.
In years past, I ran dino oil for over 6k miles, on more than one ocaasion, in a VW 1.8L Turbocharged engine. The oil did not sludge, get gooey thick, or cause any damage as far as I can tell. That was over 100k miles ago, and my VW's little 1.8T still purrs like a kitten. Dino oil is much better than many of us are willing to give it credit for.
I see you keyed off my post. I ment in 1960. Dino oil caused all kinds of sludge then. Many old timers will testify to that.
Synthetic will do the same thing if overextend your OCI today. The most important thing is you establish a reasonable OCI follow it. Make sure your engine is running in it best condition. Even if you abuse your engine and just do the basic maintanace your car will a live long life.
 
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