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Synthetic temps

5K views 33 replies 13 participants last post by  husky9 
#1 ·
The book says 0 for synthetic usage we had exactly 3 days here below 0 I have a plug in. As I read the manual 0 means zero not 32 or 15 sounds like for most temperate climates with just a couple sub-zero night plug-in would be much more cost effective?:stirpot:
 
#4 ·
The difference in oil per gallon wouldn't be worth the worry. You gotta new truck, besides even in summer the synthetic fill is the best motor protection. Start watching the sales in you area like many of us. "To Tall" is pretty good about finding good prices. Napa, Costco, Walmart.... He'll find something soon.
 
#5 ·
Walmart reduced the price of Rotella T6 5-40 to $19 a gallon. I got all they had which was 5 gallons. LOL guess the rednecks beat me to it. LOL
 
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#7 ·
Amazon currently also has the T6 for $19.16. Last 2 oil changes there price has been sam or cheaper than the area competition. Buy the single gallons, not the 3 pack. Cheaper for some reason.
 
#8 ·
I seen that also the large 2 1/2 gallon jug still alot higher priced.
 
#9 ·
Buy single gallons of Rotella T6 on Amazon using a subscription. If you have 5 items on your subscription, it comes out to about $16 a gallon. We use these for paper plates, diapers, etc. I get one gallon of Rotella T6 every 2 months, and in 6 months I have what I need for my 6 month oil change (since we never hit the mileage or engine hours).
 
#12 ·
The manual is perfectly clear the ONLY time it recommends snythetic is below zero. I guess I don't understand everyones obsession to spend more money for limited if any return. This statement is very clear although I guess that is why there are differences.
 

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#13 ·
The manual is perfectly clear the ONLY time it recommends snythetic is below zero.
If you look at the chart that shows the temperature ranges, you'll see that the 5W-40 has the widest temperature protection cold to hot. It also has a great additive package. You'll note that their recommendation doesn't say "never run 5W-40 in temperatures above 0F" and should not be read to say so.

While it doesn't say so in the manual, if you talk with folks at Cummins Onan (generators) they will tell you that it's more than acceptable to run Rotella 5W-40 T6 in their built-in RV generators. It provides even wider temperature protection, and has the additive package that they want to see in the engine. That's a key factor for them.
 
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#14 ·
ddown is right then.

There is big but, every time I use a 15w-40 I get all kinds wear metals plus an increase in potassium levels. The additives make a Blackstone report go tilt. I see where ddown was going.
 
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#15 ·
I use Rotella T6 full synthetic in my 5500 watt Cummins Onan generator, 85HP John Deere 5083E Limited Tractor, Genrac buck up power generator, Genrac 4 speed power washer, my 54" cut riding law mower, Canam Commander 1000 SXS, 2015 Ram 3500 6.7 Cummins, and Mobil1 in anything else like differentials and gearboxes. Yes all 100% synthetic in the Texas 100 plus degree heat. I also use Mobil1 XHP-222 grease on grease able bearings and bushings. The one place I use something different is in my tractor's differentials and hydraulics/transmission there I use John Deere's Hy-Gard transmission/hydraulic oil. Never a oil related issue in my life time in any of my machinery and not necessarily saying the synthetic oils have done this for me because I think a good maintenance schedule is the key to good operating equipment. To each there own because oils and additives have always been a large debate for people because some are wanting to use the best mankind makes while others won't spend the money on it or just don't care what they use. Some will do oil analysis on their oils to monitor their engine wear and most won't because of cost or they don't care or don't know. At work I do oil analysis and take it a step farther and perform vibration analysis also but that's on $1,000,000 plus motors and issues are caught before catastrophic failures happen. It saves money on these types of equipment at work but for a $10,000 Cummins diesel 6.7L it is mostly for the fun of it but it could save a person from a catastrophic failure just the same. Yes I am doing a oil analysis on my Cummins and am waiting on the results as we speak. I have never done an analysis on it so this is the 1st one on my 6.7 Cummins engine.
Good luck with your oil choice as I stated where T6 has came down in price to $19 a gallon when I used to pay $29 a gallon.
Happy Cummins engines don't smoke like they used to!!! LOL
 
#16 ·
Will full syn oils cause less crankcase smoke than dino? The EGR system would like that and so would the turbo.
 
#19 ·
Synthetic has a higher flash point and doesn't smoke or coke or varnish as easily as dyno oils. So there is less oil fumes circulating in the crank case. The intake of my turbo doesn't get much residue in the 7,000 to 10,000 miles between oil changes for me. I did get a lot more residue when I ran conventional for the first 7,000 or so miles of owning my truck (2 oil changes). After the switch to synthetic, I had almost no residue in the intake coming from the CCVF.
 
#17 ·
Conventional oils are fine in my situation a six month change guy heavy towing, IMHO It doesn't pay to go synthetic oil I get fresh oil every 3500-4000 miles it surely doesn't wear out. The 4 or five days a year it gets below zero here I plug it in. Diesels were here many years before Synthetic Oil and most commercial carriers still rely on conventional with oil sampling. If synthetic was this great nirvana I would think they would have the most to gain and would use it on every rig.
 
#18 ·
At your oil change interval I wouldn't worry about it. Like in my tractor it's changed every 300 hrs. Which would covert to about 18000 mile oil change. I can say my tractor oil is cleaner after 300 hours of use than my Cummins oil after 25 hrs of use. My tractor doesn't use DEF but does have electric controls.
 
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#20 ·
So why use 15w-40 Dino oil with all those unnecessary additives ? I'm doing 5-6000 miles per year and T6 is still a value when you get back your Blackstone Report.
 
#22 ·
What unnecessary additives are here. These are the top ten oils from TDR in the VIRGIN state. Understanding what is in oil is important. Where do you get data that the amount of additives differs between synthetic and conventional.

If you look Rotella synthetic has higher Magnesium and Moly than most, all oil has additives synthetic and conventional
 

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#21 ·
As was mentioned, look at any temp chart.
15w40 is only rated down to 0F. Where I live, 20 below is common for weeks on end.
As for as summer time use, 5W40 is still 40W at operating temp, same as 15W40. I also noticed my truck starts better and smoother when using Rotella 5W40.
 
#23 ·
I fought high metal content for two years saving money. I switched and stayed with T6 and the Blackstone report has shown a marked improvement ever since. Why buy and use 15w-40 Dino when you get 5w-40 syn T6 for the same or better price.

Price vs best lubrication T6 is the winner, just buy it on sale.
 
#24 ·
ok, here's a video that helps explain the benefits of synthetics. For 1, the biggest thing is that a synthetic doesn't change viscosity as its used. It keeps viscosity the same throughout for the most part. For 2, it has superior cold pour temps.

In the vid, the biggest take away is to compare how the 15W-40 used versus 15W-40 new flows. You can see that the used stuff has a much higher viscosity. This is an extreme test though, but it makes it easier to point out the viscosity change as an oil wears. While in the case of synthetic, there is very little difference in pourability between 5W-40 used and new. The base stock for synthetic is inherently better at maintaining viscosity.
 
#25 ·
OK switching to Shell T6. Got it all on sale for the next 4 oil changes.
 
#26 ·
Check out some of the other synthetics also Delo, Valvoline, some people just have this thing for Rotella not sure where it stems from synthetic or conventional it seems to be a regional thing. The forum "Bob is the Oil Guy" has almost every oil on earths virgin analysis and blackstone user reports make your own decisions. Also consider a FLEETGUARD - STRATAPORE - LF16035 Oil Filter synthetic media filters much better than MOPAR approved by Cummins oils only 1/2 the battle.
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3826231/2
This thread deal with long term oil usage and wear stuff interesting reading
 
#27 ·
Check out some of the other synthetics also Delo, Valvoline, some people just have this thing for Rotella not sure where it stems from synthetic or conventional it seems to be a regional thing. The forum "Bob is the Oil Guy" has almost every oil on earths virgin analysis and blackstone user reports make your own decisions. Also consider a FLEETGUARD - STRATAPORE - LF16035 Oil Filter synthetic media filters much better than MOPAR approved by Cummins oils only 1/2 the battle.
MAG 1 15W40 in 2007.5 Cummins 6.7 | Used Oil Analysis - Diesel | Bob Is The Oil Guy
This thread deal with long term oil usage and wear stuff interesting reading
I recently found out that the Donaldson DBL7349 kicks Fleetguard LF16035's arse........

http://www.cumminsforum.com/forum/2...about-donaldson-oil-filters.html#post22397577
 
#29 ·
Let me throw out this question. Would you rather do 5,000 mile oil changes using conventional oil (Mobil Delvac) or 10,000 mile changes using synthetic? I realize without actually doing an analysis I won't truly know whats best but I'd like to hear your opinion. Thanks.
 
#30 ·
The owners manual recommends to stay with the same service intervals whether using synthetic or conventional oil.
 
#31 ·
Even though the intervals are the same synthetic versus conventional, I'd still use synthetic. As noted, my main argument is that it's a stable viscosity inherently (through the base stock). Where as conventional uses the viscosity modifiers which wear out over time. I change every 6 months and tend to put anywhere between 6,000 and 11,000 miles on in that time (following the manual here). So with Synthetic, I know for sure that my viscosity hasn't changed. Also, during the winter, it does get cold and I don't have to think about the flow of my oil when I'm in the mountains.

But in the case of both oils, the detergents wear out over time the same way. It's just that synthetic offers a more stable viscosity. Lastly, I've always noticed that there seems to be elevated levels of copper when switching between oil brands in our municipal fleet. Seems like the detergent packages remove the thin protectant layer from the previous oil brand in the oil coolers until the new brand of oil re-establishes some protecting layer. then the copper returns to normal levels among the fleet. At least that's the theory our tribologists have. No actual harm to the vehicles but it always strike me as odd and tends to last for 1 or 2 oil changes.
 
#32 ·
The EGR systems on these new trucks really don't help the oil.
 
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