Oil Deal!!!

[OLEJOE]

Amazon has Rotella T6 5w40 for $52.44 for 3-1 gallon jugs and free shipping for Prime members. I don’t need any right now but can’t pass this up. Just saying

 

[Randomrunner12]

Dang not a bad price. I just bought a 2.5 gal of the same stuff from walmart for 56$. Thinking of taking it back and getting the T5 15w-40 instead.

 

[DavidC]

That 5w worries me for a 99 that Cummins spec's out at 15w. Might be a little to light, ok for newer that came with 5w. They do have a 15-40 T6 but is quite pricier.

 

[OLEJOE]

The T6 15-40 is what I have in mine right now. Mine doesn’t need to be changed til May but I’ll probably hold on to the 5-40 til November. I’ve got a long trip planned with my TT this summer and I’ll probably run 15-40 but haven’t decided what flavor yet.

 

[Cummins12V98]

Personally will only run 15-40. AMZ/OIL for example the pour point is only 3 degrees different between the 5-40 and 15-40.

So is it really worth it??????

15-40 DME -40

5-40 DEO -43

 

[kthaxton]

Personally will only run 15-40. AMZ/OIL for example the pour point is only 3 degrees different between the 5-40 and 15-40.

So is it really worth it??????

15-40 DME -40

5-40 DEO -43

If there was a reason NOT to run a 5w40, then it wouldn't be worth it....but since 5w40 is perfectly fine (both in practice and per Cummins/Ram) it is worth it.

 

[Randomrunner12]

I just figure Texas doesnt really get cold enough to really need the 5w-40 so I am ok with the 15w-40. I also drive more then most in a month just in city driving so I change my oil every 5 months and after my last oil change of running the Amsoil Sig series 5w-40 and there filter and it cost me 160$ i decided that wont be happening again.

Myself and My dad had always ran T5 in my old Ford 7.3l, his 99 2500, and this truck when new and non-deleted. Never had any issues. Again these are all my experiences and preferences. So please no one start ANOTHER OIL WAR. lol

 

[OLEJOE]

I’d use what has been working for you. Mine is a new truck and first diesel p/u. Drove class 8’s for 40 years but they weren’t mine and had to use what ever oil was provided. Didn’t have to pay for it either. Oil or truck or maintenance. Different game now.

 

[Cummins12V98]

Someone brighter than me can decipher this info. I think the 15-40 is better?

The 5-40 is a bit more $.

 

[OLEJOE]

They both look good to me. The 5-40 and 15-40. With stock non deleted trucks, the sulfated ash looks better on the 5-40 to me. Also the lighter 5-40 should flow faster at start up with the same protection at operating temperature. Just theory. I’ve used 15-40 for 40 years.

 

[Ozymandias]

Does one believe that this Engine from Cummins runs in a hundred of applications in probably 180 Countrys around the World with just the oil that is available there?

 

[OLEJOE]

Absolutely

 

[mfurrh55]

I just figure Texas doesnt really get cold enough to really need the 5w-40 so I am ok with the 15w-40. I also drive more then most in a month just in city driving so I change my oil every 5 months and after my last oil change of running the Amsoil Sig series 5w-40 and there filter and it cost me 160$ i decided that wont be happening again.

Myself and My dad had always ran T5 in my old Ford 7.3l, his 99 2500, and this truck when new and non-deleted. Never had any issues. Again these are all my experiences and preferences. So please no one start ANOTHER OIL WAR. lol

i can get amsoil for you cheaper then that, also i have a friend in Plano that will get it for you at dealers price(his ) price and wont upcharge you, let me know and ill get you his contact number, he goes to warehouse and picks it up,

 

[mfurrh55]

My truck always used a couple qts. In 5000 miles on 5-40, doesn't use any on the 15-40, so all i run is the 15-40, I run Schaefers full synthetic 15-40 and it doesn't use any in 12000 mile oil change, Schaefers is a green oil

 

[AH64ID]

That 5w worries me for a 99 that Cummins spec's out at 15w. Might be a little to light, ok for newer that came with 5w. They do have a 15-40 T6 but is quite pricier.

Don't be worried about it. Nothing really changed from when 15w-40 was the only spec to when synthetic 5w-40 was offered as a spec. Flat tappets, rockers, HUGE main bearings, etc.. all basically the same and were from 98-18. That being said there are several quality synthetic 15w-40's that have great pour points.

If there was a reason NOT to run a 5w40, then it wouldn't be worth it....but since 5w40 is perfectly fine (both in practice and per Cummins/Ram) it is worth it.

There isn't a reason not to run it, but there are reasons why a synthetic 15w-40 can be better choice... unless you need that extreme cold flow.

Just looking at the above posted photo, other manufacturer specs are sometimes harder to find, the big things I look for in a diesel oil are Viscosity at 100°C, NOACK Volatility, and High Temp/High Sheer Viscosity. Other stuff is also important, but these 3 are big ones for me.

The 0w-40 has the highest 100°C viscosity, .1 higher than the 15w and .3 higher than the 5w. When I switched from an oil with a 100°C viscosity of 15.0 to one with 15.6 I saw 3-5 more psi at 2,000 rpms and the oil ran 5° cooler at cruise. While towing it held 2-3 psi more and slightly cooler. This was with aftermarket oil temp and pressure on my 05. So I like this number a little higher for heavy towing. Win 0w-40.

The NOACK Volatilty always increases the higher the multiweight spread is, which is why the 15w-40 will burn off 80% less than the 5w-40 and 113% less than the 0w-40. Win 15w-40.

High Temp/High Sheer. Higher is better, especially when you look at how much power these things are making now. 15w-40 win.

So even thou the 0w-40 has a higher 100°C viscosity it's only by .1, so I'll take that minor decrease as it's still a better performing oil under heavy load than the others. I do run the listed Amsoil 15w-40.

Based on the published specs from Rotella the 5w-40 has a higher 100°C viscosity than the 15w-40 by .2, but I cannot find the NOACK Volatility rating or HT/HS on either one. I can't find anything on their 0w-40 for CK, but the CJ oil was quite thin for a 40wt.

That being said, nearly all CK oils are better across the board than the CI oils everyone was so in love with and afraid to lose. TBN doesn't mean nearly as much anymore with ULSD.

Often 15w-40 synthetics are more expensive than 5w-40 synthetics too. Just depends on what you want to run... conventional 15w-40 is still going to be the cheapest option for above 0° use... I know it's rated lower but I personally wouldn't based on some freezer tests I did at -10°F.

So I would pick your oil based on pour temp requirements, and then personal preference... just my 0.02 on oil selection.

Not trying to start an oil war.. just pointing out some research points if people are shopping.

 

[Cummins12V98]

AH64ID, thanks for the info!

 

[kthaxton]

So considering those subtle differences likely not discernible in actual use, is it worth it to get a fantastic deal on 5w40? Yes it is.

 

[Randomrunner12]

i can get amsoil for you cheaper then that, also i have a friend in Plano that will get it for you at dealers price(his ) price and wont upcharge you, let me know and ill get you his contact number, he goes to warehouse and picks it up,

That sounds good for next time, Shoot me a text with his info.

 

[Cummins12V98]

So considering those subtle differences likely not discernible in actual use, is it worth it to get a fantastic deal on 5w40? Yes it is.

I agree “IF” it’s an oil you typically use.

 

[AH64ID]

So considering those subtle differences likely not discernible in actual use, is it worth it to get a fantastic deal on 5w40? Yes it is.

You'll never see a difference with the OE oil pressure/temp gauges, since they are fake. Install a pair of real gauges and you’ll see a discernible difference... but it likely doesn’t matter for average use and motor life.

The biggest thing people are likely to see is an increase in oil consumption with 5w-40.