happy
Viper Owner
i have a 02 gts and just purchased it, i did some research and it seems i can run the same rotella 15/40 oil in my new viper as i use in my new cummings?? Is this right?? Just wanted to clarify this? Thanks guys!!
so what does everyone seem to be using???
- Thread starter happy
- Start date
99 R/T 10
Enthusiast
Yes and some of the smarter people not only recommend it, but use it too 
sniper1
Viper Owner
Thats about the most retared crap I've ever heared 
... There is a specific tolerance between the moving parts, bearings etc. which will only allow a certain weight viscosity providing enough lubrication protection in those areas. That is why the manufacturer recommends the oil by weight because that is the oil used in testing the engine for its peak performance, longivity and reliability... 
... There is a specific tolerance between the moving parts, bearings etc. which will only allow a certain weight viscosity providing enough lubrication protection in those areas. That is why the manufacturer recommends the oil by weight because that is the oil used in testing the engine for its peak performance, longivity and reliability... Not to mention that they change oil recommendations to meet fuel consumption requirements first....
happy
Viper Owner
so the rotella 15/40 is perfectly fine even up here in Canada where i live, i dont see as high of temp in weatehr as you guys do down south!
happy
Viper Owner
so what other options do i have to go with?? Some one said the motoul oil can you use it?? i used to use thre gear oil in my new sti for the 6 speed tranny very good stuff!! if i can use it ill buy it instead!! What grade do they call for from factory?
Martin
Enthusiast
I'm running Rotella T Synthetic 5w/40 in all my cars, trucks, and tractor now. It's a little more expensive than the regular Rotella, but I like the idea of running a synthetic - especially on things that have a turbo and I don't spend a whole lot of time letting the turbo cool down after running hard. The synthetic won't coke up like a conventional oil might.
You can get it at Wal Mart for cheap - every once in a while they put it on sale for around $15 a jug, and sometimes even less (I bought their whole stock once when they put it on sale for $12 a jug).
Dads Toy
Enthusiast
I am confused. My understanding on Oil weights is depending on the climate you live in. I thought the first number 5W30 was for climates with colder temps like below 30 degrees and the second number 10W40 was for warmer temps. so if you live in a warm area you want 10W40 vs 5W30 in cold climates.
ryan94rt10
Viper Owner
tom our oil guru, will come on here and tell you to run the 0w-30 mobil 1....just wait!!
99 R/T 10
Enthusiast
Tom's been busy lately.................................................. getting busier
whitebluevipe
Enthusiast
Thats about the most retared crap I've ever heared
exactly, just use what the engineers designed it to use.
sniper1
Viper Owner
Good luck with that thought process... Would you like some 75/90 to go with that?
75/90 for you too ?
Straight 90 weight for you though!
Vman455
Enthusiast
Thats about the most retared crap I've ever heared
If that's true, then why did the factory-fill switch from 10W-30 to 0W-40 in the middle of Gen III production?
For the record, I will trust an ex-auto fluids formulator who has nothing to gain or lose by recommending a specific oil or weight (i.e. Tom recommending 15W-40 or 5W-40 diesel oil) long before I trust the OEMs....
sniper1
Viper Owner
My point exactly, they tested it right up into the mid production and realized the closer tolerances were in need of a lesser weight oil to protect and lube the engine properly. RESEARCH
Vman455
Enthusiast
Well, in that case, I have even less reason to trust the engineers. If they didn't discover in the years of testing before production started that the engine "needed" a different oil than what they were using...?
When it comes down to it, use what you want in your car. Mine's running synthetic diesel 5W-40, per the fluid deity's recommendations.
When it comes down to it, use what you want in your car. Mine's running synthetic diesel 5W-40, per the fluid deity's recommendations.
sniper1
Viper Owner
I agree with you to an extent, but even the experts don't always make the best decisions in the beginning, resulting in changes for the better of their product and the consumer.
I do and I will as I'm certain you will and do, but research on our own behalf is recommended so you know for certain the fluid deity is making the best decision for you
happy
Viper Owner
so rotella it is right on thanks guys!! This oil is the best when it comes to diesels over 700 000 miles on some peoples trucks still run like champs!! Ill give it a whirl in my new gts! Thanks
Tom F&L GoR
Enthusiast
OK, sorry for the late entry and I'll try to address everyone's questions.
You can run a 15W40 diesel oil. A diesel oil has 2X-3X the performance additives as a gasoline engine oil, so you have more than enough anti-wear and cleanliness features. The 15W-xx means satisfactory starting down to -20C or -5F. The diesel oils are not reducing the zinc-phosphorus anti-wear additives like the gasoline engine oils are.
Canadians might want something with better cold flow properties. Diesel oil comes in a synthetic version in SAE 5W-40. Mobil's version is called Delvac 1, Rotella and Chevron Delo have theirs also. These are so highly formulated I don't care which you use.
Oil viscosity is graded by the two numbers, a xxW and then the second -YY number. One does not relate to the other in the sense that you can have a single grade SAE 40, a 15W-40, a 10W-40, a 5W-40, and a 0W-40. At 100C, they are all the same!! The viscosity is between 12.5 to 16.3 cSt. At low temperatures, the lower the "W" number, the lower the temperature at which it will still be sucked up through the oil pickup tube and be promptly circulated throughout the engine.
OEMs also look to thinner oils for fuel economy. Physics and engine testing show this is a slight trade off with longevity. The thicker the oil film, the less wear occurs. The real evidence of retardation is that OEMs are willing to force oil companies to reduce the antiwear additive level and viscosity at the same time because they get better fuel economy and because they use roller lifters that presumably don't need as much antiwear additive. Of course, ask any engine builder if they have problems with flat tappet cams these days... have you noticed the explosion of break-in oils and "hot rod oils?"
Another good choice is Mobil's 0W40 that is now factory fill. As discussed above, the viscosity grade is good for low temp starting and high temp operation. Read the label, though. It meets ACEA standards which are their API tests. The true advantage is that since European passenger cars often have diesel engines, the Mobil oil actually meets many diesel engine performance criteria. So when you buy Mobil 0W40, you are just about buying a diesel oil anyway.
Dad, regarding your 10W40 vs. 5W30 question. Those viscosity grades are traditionally mineral oils and to move either the first number lower or the second number higher is a formulation difficulty. (i.e. a 5W40 or 10W50 mineral, or a 0W30 or 5W40 mineral) With synthetic base oils it is easy because the synthetics have a built in multigrade like characteristic. So you could use a 5W40 year round. Or use a 0W40 year round because lower "W" just ensures better starting pumpability.
Ha, ha 75W-90 gear oil. In theory you could. These numbers used to label a viscosity have nothing to do with the actual measurement. They might as well be ggWpp or something. In gear-oil-speak, the 75W provides adequate flowability down to -40C. The -90 is roughly equivalent to a 50 grade. So you really could start the engine at low temperatures and run at high temperatures. It just would have all the wrong additives for wear protection and cleanliness.
For the record, I live 70 north of NY city. When cold it may get to single digits. I use a 15W40 diesel oil (cheapest name brand I find at Walmart.) I probably don't drive unless in double digits, mostly because if it's that cold there is still snow on the driveway and I can't get it out to the road. But I don't hesitate on 15F clear days.
Let's compare 10W30 to 0W40 again and do it this way:
At -35C the 10W30 will not flow but the 0W40 will.
At 100C the 10W30 has less bearing film thickness than the 0W40.
Hmmm... 0W40 flows better and protects bearings better.
OK class, any questions?
You can run a 15W40 diesel oil. A diesel oil has 2X-3X the performance additives as a gasoline engine oil, so you have more than enough anti-wear and cleanliness features. The 15W-xx means satisfactory starting down to -20C or -5F. The diesel oils are not reducing the zinc-phosphorus anti-wear additives like the gasoline engine oils are.
Canadians might want something with better cold flow properties. Diesel oil comes in a synthetic version in SAE 5W-40. Mobil's version is called Delvac 1, Rotella and Chevron Delo have theirs also. These are so highly formulated I don't care which you use.
Oil viscosity is graded by the two numbers, a xxW and then the second -YY number. One does not relate to the other in the sense that you can have a single grade SAE 40, a 15W-40, a 10W-40, a 5W-40, and a 0W-40. At 100C, they are all the same!! The viscosity is between 12.5 to 16.3 cSt. At low temperatures, the lower the "W" number, the lower the temperature at which it will still be sucked up through the oil pickup tube and be promptly circulated throughout the engine.
OEMs also look to thinner oils for fuel economy. Physics and engine testing show this is a slight trade off with longevity. The thicker the oil film, the less wear occurs. The real evidence of retardation is that OEMs are willing to force oil companies to reduce the antiwear additive level and viscosity at the same time because they get better fuel economy and because they use roller lifters that presumably don't need as much antiwear additive. Of course, ask any engine builder if they have problems with flat tappet cams these days... have you noticed the explosion of break-in oils and "hot rod oils?"
Another good choice is Mobil's 0W40 that is now factory fill. As discussed above, the viscosity grade is good for low temp starting and high temp operation. Read the label, though. It meets ACEA standards which are their API tests. The true advantage is that since European passenger cars often have diesel engines, the Mobil oil actually meets many diesel engine performance criteria. So when you buy Mobil 0W40, you are just about buying a diesel oil anyway.
Dad, regarding your 10W40 vs. 5W30 question. Those viscosity grades are traditionally mineral oils and to move either the first number lower or the second number higher is a formulation difficulty. (i.e. a 5W40 or 10W50 mineral, or a 0W30 or 5W40 mineral) With synthetic base oils it is easy because the synthetics have a built in multigrade like characteristic. So you could use a 5W40 year round. Or use a 0W40 year round because lower "W" just ensures better starting pumpability.
Ha, ha 75W-90 gear oil. In theory you could. These numbers used to label a viscosity have nothing to do with the actual measurement. They might as well be ggWpp or something. In gear-oil-speak, the 75W provides adequate flowability down to -40C. The -90 is roughly equivalent to a 50 grade. So you really could start the engine at low temperatures and run at high temperatures. It just would have all the wrong additives for wear protection and cleanliness.
For the record, I live 70 north of NY city. When cold it may get to single digits. I use a 15W40 diesel oil (cheapest name brand I find at Walmart.) I probably don't drive unless in double digits, mostly because if it's that cold there is still snow on the driveway and I can't get it out to the road. But I don't hesitate on 15F clear days.
Let's compare 10W30 to 0W40 again and do it this way:
At -35C the 10W30 will not flow but the 0W40 will.
At 100C the 10W30 has less bearing film thickness than the 0W40.
Hmmm... 0W40 flows better and protects bearings better.
OK class, any questions?
sniper1
Viper Owner
Good info and fuel milage is a plus however it's a VIPER ! You forgot to mention that by using the heavier weight oils, it will rob horsepower (parasitic weight)and labor the oil pump built for the weight specific oils as well as not allow for PROPER OILING of engine parts with the much closer tolerances modern engines have.
I'll just keep on using Synthetic 10w30 in mine, It's a happy medium all said and done.
I'll just keep on using Synthetic 10w30 in mine, It's a happy medium all said and done.
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sniper1
Viper Owner
Tom F&L GoR
Enthusiast
Good info and fuel milage is a plus however it's a VIPER ! You forgot to mention that by using the heavier weight oils, it will rob horsepower (parasitic weight)and labor the oil pump built for the weight specific oils as well as not allow for PROPER OILING of engine parts with the much closer tolerances modern engines have.
I'll just keep on using Synthetic 10w30 in mine, It's a happy medium all said and done.
When Texaco sponsored several race teams in NASCAR, CART, F1 the biggest difference between best and worst oil was ~13 HP out of ~800HP, and this was an 16,000 RPM engine. The comparison was a street 20W50 vs. low friction, low viscosity oil. More of the horsepower difference is due to windage, not fluid resistance in the bearings.
Windage is at least the square of RPM difference, so in a 5,000 RPM Viper engine we're talking 4 HP at most. And since we're comparing 10W30 vs. 5W40 (smaller change) it is probably less than 4HP.
The horsepower requirement for pumping is related to the "W" number, since at this point in the engine the oil is cooler. A 0W-anything will take less to push around than a 10W-anything.
sniper1
Viper Owner
4 HP here 13 HP there 7 HP over there, IT ALL ADDS UP. Also I didn't mean fluid resistance in the bearings was an issue, I meant heavier/thicker oils even being able to move through those bearing areas rapid and efficiantly enough to lubricate and cool properly. Not to mention the issues of over taxing the oil filter itself as the oils attempt to flow through it with all the combustion contaminants in them.
I refuse to believe 15w40 is healthy for any Viper engine and I barely believe that 0w oils are either, so good luck to those who use either of them in the long run... Thanks for the food for thought.
Tom F&L GoR
Enthusiast
Pumpability is measured by two laboratory tests that replicate the results of studies over many engine families. These tests evaluated time to **** up cold up through the oil pickup tube, and then time to produce oil pressure at a point near the farthest oil passage (not a nearby location like the oil pressure gauge is usually plumbed into.) So if the oil is satisfactory down to -15C for example, it will for sure be satisfactory at any temperature warmer than that. In other words, the "W" number already accounts for the efficient movement through bearing areas. As long as you don't operate below the temperature for which the oil meets the requirements there is no problem.
One reason diesel oils are different is that with the very long oil drains, the engine combustion contaminants build up over a longer time period. Soot and blowby are tremendously bad actors and do thicken the oil. Therefore diesel oils have large doses of dispersants, which keep the contaminants from thickening the oil and causing unnaturally high oil pressures or damage to filters. You have less chance of popping a filter with diesel oil.
The "W" number and the second number really have to be disconnected. As mentioned previously, you can mix and match these to produce a variety of viscosity grades. Anybody using a 10W30 can absolutely use a 5W30 or 0W30 with only an improvement in starting and no loss in warmed up features. (absent any discussion of additives in the oil.)
ryan94rt10
Viper Owner
Let's Compare 10w30 To 0w40 Again And Do It This Way: At -35c The 10w30 Will Not Flow But The 0w40 Will. At 100c The 10w30 Has Less Bearing Film Thickness Than The 0w40. Hmmm... 0w40 Flows Better [u said:
See I Told Ya Soooooo!:d
Greg Good Cylinder Heads
Enthusiast
On an engine with a good oiling system you can push things a little on the weight of the oil and gain some power, but not on a Viper. Your primary concern here needs to be with protecting engine parts (rod bearings), not trying to make a few extra horsepower.
Let the engine idle for about 15 seconds when you first start it, don't *whack* the throttle until the oil temp is up....and it's ok to run a thicker oil.
BTW, I like a 15W50 oil.
