Shell Rotella - T4, T5, or T6???

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mvweebles

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Weebles
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1970 Willard 36 Trawler
I need some oil - have decided on Shell Rotella due to local availability. Question is T4 (oil), T5 (synthetic blend), or T6 (synthetic)? My inclination was T6 but I came across this YouTube review and looks like T5 might be a better choice. I grabbed a screenshot of the findings to save y'all 11-mins of your life listinening to an unscripted narrator turn a 2-min vid into a 12-min one.

Engines: Old-school Perkins 4.236 75hp taking 2-gals; Northern Lights 6kw with 3-cyl Shibaura natural.

Thoughts?

Peter
Shell Rotella Compare.jpg
 
Peter best / most applicable article I've found relative to marine application can be found on my Bacchys Website - Useful Links - Cox Eng Yacht Eng Oils
https://dkloeber.wixsite.com/bacchus/links
Latest version & syn not always the "best" choice. Our engines are not what they are optimized for.
 
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Peter best / most applicable article I've found relative to marine application can be found on my Bacchys Website - Useful Links - Cox Eng Yacht Eng Oils
https://dkloeber.wixsite.com/bacchus/links
Latest version & syn not always the "best" choice. Our engines are not what they are optimized for.

Thanks - helpful.

Here is the direct link. In short, old engine, old oil. CF-4 would be my approximate vintage for the Perkins - T4 would be the closest of the three I posted. Will have to look at the NL 6kw.

https://26ed2d06-9e49-4586-8f39-2a0...d/3bd504_eec473b8b1144dccb338ca2cd51b9dbc.pdf

Honestly, I'd heard that synthetics shouldn't be run in older engines, but have heard more recently that it's not an issue. Go figure.

Peter
 
My engines are from 1979. I don't think they had synthetic oil back then. And the additives were no where near as good as today. I'll keep using good old petroleum.
 
My John Deere was built in 2013. Manufacturer specified regular diesel motor oil like T4. I had higher than I expected wear metals with the manufacturer's premium oil. After the warranty period was up, I switched to Rotella T4. Wear metals declined to well below Blackstone's universal averages. Like Rotella T4 and have been using it for a long time. My Dodge pickup with the Cummins 6BT 220 HP engine now has close to 525,000 miles on it.

Ted
 
Rotella T4 for a normally aspirated diesel. T5 only if T4 is not available, IMO.
We tend to change engine oil long before the advantages of synthetic really help.
 
Believe Cummins suggests you not use semi or full synthetic. Don’t know the reason but have avoided them. Would ask your engine manufacturer for guidance. If no longer in business a professional like Steve D’A
 
Realistically, any of the 3 are likely to do just fine in your engine. I use HDEO oils (typically Rotella or Delo) in most of the engines I take care of. I generally swap between those 2 brands based on price and availability.

Currently I've got a car at home with Rotella T6 5W-40 in it, another car with Delo 5W-40 syn, same in the snowblower too. Just put T6 5W-40 in the dinghy outboard. Boat engines and gen all have Delo 15W-40 semi syn in them. I used to use T4 or the basic Delo in the boat, but at some point I started finding the semi-syn versions cheaper than the dino stuff, so I switched.

I've never seen an issue from using synthetic in an engine that doesn't need it. Realistically, as long as an oil meets the basic needs of an engine, is an appropriate viscosity, and is changed before it's worn out then you should be in good shape. As OCdiver found, some engines can be a little more picky than the basic specs indicate. So oil analysis is a good idea to confirm good wear metals and determine how long the oil you've chosen is holding up.
 
Old school engine, go with old school oil. No need for the synthetic.

pete
 
Fairly sure a previous TF thread established synthetic is not actually synthetic.
 
Ill jump in saying older motor no need for synthetic oil. Not as many tight clearances oil is forced throu compared to a modern electronic motor.
 
Fairly sure a previous TF thread established synthetic is not actually synthetic.
I am under the impression they are all blends that have a dyno base.
 
Here is the direct link. In short, old engine, old oil. CF-4 would be my approximate vintage for the Perkins - T4 would be the closest of the three I posted.

Honestly, I'd heard that synthetics shouldn't be run in older engines, but have heard more recently that it's not an issue. Go figure.


I've read that, too. True or not, I'd use T4 in your case. No significant advantage from the synthetics, I think.

Might be different if you don't want/plan to change oil annually... but I think I'd check with a Perkins and/or Shibaura (?) guru before you do that.

We had Cummins 450s in the previous boat, and they specifically recommended not using synthetic.


I am under the impression they are all blends that have a dyno base.

Maybe, but some (like T6) say "full synthetic" and I'd have guessed they can't fudge the language too much.

-Chris
 
I would also stick with T4. With any of those you won't have an oil related failure.
 
Fairly sure a previous TF thread established synthetic is not actually synthetic.


There are a couple types of synthetic base stock. Some don't consider a group III synthetic to be actually synthetic, but only groups IV and V. Group III is basically a synthetic that's made using petroleum as an input material.
 
T4 even though T5 has better anti-wear additives and a smidgen better detergent additives?

Peter
 
Looking at the additive numbers, I'd lean slightly towards the T5 for an older engine design, although I expect it wouldn't make a big difference in wear between any of them. The T4 is slightly thicker at high temps, but I wouldn't expect that small difference to matter in most cases.
 
T4 even though T5 has better anti-wear additives and a smidgen better detergent additives?

Peter



Maybe this is overly simplistic, but if the engine calls for grade C-whatever, isn’t that what you should use? Each new C designation is backwards compatible, so I guess I don’t see what the fuss is all about. Use a reputable brand that meets the specs and go cruising. Really, have you ever heard of an oil related engine failure when the manufacturer’s recommended oil spec was used?
 
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Maybe this is overly simplistic, but if the engine calls for grade C-whatever, isn’t that what you should use? Each new C designation is backwards compatible, so I guess I don’t see what the fuss is all about. Use a reputable brand that meets the specs and go cruising. Really, have you ever heard of an oil related engine failure when the manufacturer’s recommended oil spec was used?

Some complications due to being south of border. The oil I find in Mexico is either a brand I am not familiar with, or one that I am pretty sure is at the lower end of the quality heap (STP). Finding diesel oil is a subset. So I will grab it in San Diego. All three on the shelf, and price differential is not an object - just trying to decide on which one. I initially thought the T6, but seeing the comparison on T5, looked compelling. I realize any of them will provide excellent lubrication, much better than the oils available when my circa 1990 Perkins was built.

I pinged a very knowledgeable friend who happens to have a Perkins 6.354. While I didn't ask the synthetic vs conventional question, he said he runs Delo 400 15-40 (CK-4 or CJ-4) and said the Shell Rotella equivilent is fine. I believe any of the three Rotella Oils are CK-4/CJ-4 compliant.

Peter
 
So I did a bit more research. All three Rotella oils - T4, T5, and T6 - are CK-4 and CJ-4 compliant. There are long lists of engine manufacturer approvals for all three (though not Perkins which is understandable).

Further, I looked at the data sheet for each and summarized several of the metrics. The appear more similar than different. My best-guess is the pour-point and viscocity numbers would make a difference for truckers who operate in very cold conditions, but for the most part, subtle differences for my engines would be meaningless. That said, i was impressed with the higher anti-wear characteristics noted in the video I originally posted. I will probably go T5, but would be happy with the other two as well, but would be wasting a few bucks

Peter
Datasheet Compare T4-T5-T6.jpg
 
I have been using a variety of synthetic oils in my old International/Ford 7.3L turbo diesel for a good two decades now. During that time, I have NOT changed at the recommended 5,000 miles but between 10,000 to 16,000.

Did have a wear increase, once, for some unknown reason that I have a suspicion about, but after several oil changes, the wear was back to normal. The wear was not horribly bad but bad compared to the usual numbers. Other than that one oil change, the wear has been low on the engine, lower than what Blackstone sees in the average of all of the samples they get for a very popular engine.

I test the oil after every oil change.

I do this to save time on oil changes and for better cold weather starts. With 15w40 oil, I would have to use a engine block heater in the winter to start the truck. It would start without the heater but it surely could not have been good on the engine. Even running that engine block heater on a timer, the cost added up and help pay for the more expensive oil and the oil test.

If one is running a boat where the ER does not get near freezing or below freezing, and one is changing oil on the recommended hours/miles/time schedule, short of some other unlikely reason, why run synthetic?

My truck engine is at almost 300,000 miles and is holding up fine but I can't say that for the rest of the truck that is going to be 22 years old this year.

Later,
Dan
 
So I did a bit more research. All three Rotella oils - T4, T5, and T6 - are CK-4 and CJ-4 compliant. There are long lists of engine manufacturer approvals for all three (though not Perkins which is understandable).


Outside the US, Rotella is sold as Rumina, something like that. Could be Perkins approves it under that name.

Took me a while to track down that equivalency when I was shopping for supplies while prepping for our next oil change.

-Chris
 
Maybe this is overly simplistic, but if the engine calls for grade C-whatever, isn’t that what you should use? Each new C designation is backwards compatible, so I guess I don’t see what the fuss is all about. Use a reputable brand that meets the specs and go cruising. Really, have you ever heard of an oil related engine failure when the manufacturer’s recommended oil spec was used?
Yes new classifications are developed, primarily for OTR & newer emission stds & equip, and tested for those applications. Do you think any oil mfg do performance / compatible testing for marine application? I don't know, but I doubt it.
This is the best / most applicable study for marine application I have seen.

http://coxeng.co.uk/engine/oil-for-yacht-engines/

All other studies claiming the latest is greatest are OTR based. The above does cite a few instances where problems were attributed to the use of latest synthetics in marine application.
If you simply check an eng mfg recommendations such as Cummins, they produce many more OTR eng than marine and I bet don't do separate testing. Caution interpreting studies & recommendations is important IMO.
 
Yes new classifications are developed, primarily for OTR & newer emission stds & equip, and tested for those applications. Do you think any oil mfg do performance / compatible testing for marine application? I don't know, but I doubt it.
This is the best / most applicable study for marine application I have seen.

http://coxeng.co.uk/engine/oil-for-yacht-engines/

All other studies claiming the latest is greatest are OTR based. The above does cite a few instances where problems were attributed to the use of latest synthetics in marine application.
If you simply check an eng mfg recommendations such as Cummins, they produce many more OTR eng than marine and I bet don't do separate testing. Caution interpreting studies & recommendations is important IMO.
"Do you think any oil mfg do performance / compatible testing for marine application? I don't know, but I doubt it."

Why would they test for marine applications? Aren't all marine diesels just marinized "dirt" diesels?
 
"Do you think any oil mfg do performance / compatible testing for marine application? I don't know, but I doubt it."

Why would they test for marine applications? Aren't all marine diesels just marinized "dirt" diesels?
Yes. My point was marine & off road usage different than over the road applications with emission limits and associated systems that require different oils in some cases.
IMO.
Although all newer oil formulations are backward compatible...
Newer is not necessarily Better for All applications
 
Yes. My point was marine & off road usage different than over the road applications with emission limits and associated systems that require different oils in some cases.
IMO.
Although all newer oil formulations are backward compatible...
Newer is not necessarily Better for All applications
Newer is not necessarily better in all applications. Which applications and why? Not trying to be a wise guy, I just want to learn.
 
Newer is not necessarily better in all applications. Which applications and why? Not trying to be a wise guy, I just want to learn.


Occasionally you find an engine that has somewhat specific oil needs that aren't met as well by all newer oils.

An example being older engines with flat tappet cams. Depending on how aggressive the cam profile is, they can require significant amounts of anti wear additives like ZDDP. Most newer oils have reduced ZDDP levels in them (although it varies depending on the oil) as high ZDDP levels can poison catalysts if there's any significant oil consumption. For many engines, the lower ZDDP (especially with other changes to the additive packages) is a non-issue, but for some it's a concern and you either need a ZDDP additive, or to find oils with higher ZDDP levels.

In most cases, newer oils are backwards compatible. But there are exceptions (one being the 2 stroke Detroit oil needs). If in doubt, oil analysis to monitor for wear metals, etc. is a good idea.
 
Newer is not necessarily better in all applications. Which applications and why? Not trying to be a wise guy, I just want to learn.

I'm trying to learn too. Best I can tell, you want oil that meets CK-4 and CJ-4 standards. You know what? They all do - even the el-cheapo STP I found here in Ensenada. So there's something behind the curtain that's mostly hidden from view since the additive packages used by the refiners are proprietary. BTW - I think there are only a small handful of refineries producting lubricants - Shell (Rotella). Chevron (Delo), BP (Castrol), Exxon (Mobile). Guessing they do contract refining for the others.

In the end, I ended up going with T5, mostly because the higher anti-wear numbers on the chart I posted. I poked around the internet quite a bit and found some anecdotal stories about how synthetics should not be used in older engines, but they seemed to be older stories. In the last 15-years, quite a few old-school truckers with older equipment started using synthetics and now swear by them.

Thanks for the input and discussion.

Peter
 
I'm trying to learn too. Best I can tell, you want oil that meets CK-4 and CJ-4 standards. You know what? They all do - even the el-cheapo STP I found here in Ensenada. So there's something behind the curtain that's mostly hidden from view since the additive packages used by the refiners are proprietary. BTW - I think there are only a small handful of refineries producting lubricants - Shell (Rotella). Chevron (Delo), BP (Castrol), Exxon (Mobile). Guessing they do contract refining for the others.

Yep, as long as one meets or exceeds the recommended oils standard, one is on the right path. I used to buy JD branded 0W40 oil. I don't think JD has an oil refinery somewhere. At that time, I could get it for a dang good price for a very good oil and I was at the JD dealer frequently enough to buy a bucket. My truck is so old it does not mention synthetic oils, and the naysayers said don't use it. The oil meets the oil standard per the manual so I started using a variety of synthetics.

I have also heard to not switch oils. Use an oil and stick with it. I have not done that either. I used Shell and Delo 15W40 oils for the first few years, then switched to 0W40 and 5W40 oils from JD, Shell, and I think Mobile for one change.

Later,
Dan
 
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