Community Forums

Dhilbe · 07-07-2020, 07:18 PM

Just had my Newmar Dutchstar oil/filter changed. I see they used Rotella 15W40. I wanted to buy some extra oil to have handy when on the road. I searched Rotella...but everything comes up as T4, T5, T6. I don’t know if they used T4/T5/T6 in my oil change. Any idea which oil I should purchase? Thanks, Dave

L-M-L · 07-07-2020, 07:29 PM

Call the company that did the oil change and ask which type they used. That would be the best way to find out.

Pigman1 · 07-07-2020, 07:31 PM

T-4 Dino
T-5 Blend
T-6 Synthetic

AFChap · 07-08-2020, 06:23 AM

I buy the dino 10w40 at Walmart. They probably have the others too.

Chargerman · 07-08-2020, 06:26 AM

I use T5. To me paying extra for synthetic in a diesel is a waste of money as it does not extend the change interval

grindstone01 · 07-08-2020, 06:36 AM

Quote:

Originally Posted by Chargerman

I use T5. To me paying extra for synthetic in a diesel is a waste of money as it does not extend the change interval

Running synthetic is more than just extended oil changes. Using synthetic has been proven to run cooler in your engine which is a direct result from less friction. I use synthetic in my motorcycle and truck transmission and will run temperatures 10-15 degree cooler.
To the OP, Walmart sell's Rotella 15W40 which is not synthetic oil (it's still adequate oil, just not the best).

Unplanned Tourist · 07-08-2020, 07:02 AM

For just topping up, standard dino oil 15W40 will be just fine.

Your engine was designed to run just fine with it.

Going to synthetic is fine, but not necessary.

It's like buying extra insurance, not everyone does it, but some are uncomfortable without it.

Not trying to start a dino versus synthetic war here. Just stating the facts.

Happy Glamping.

Chargerman · 07-08-2020, 09:56 AM

Quote:

Originally Posted by grindstone01

Running synthetic is more than just extended oil changes. Using synthetic has been proven to run cooler in your engine which is a direct result from less friction. I use synthetic in my motorcycle and truck transmission and will run temperatures 10-15 degree cooler.
To the OP, Walmart sell's Rotella 15W40 which is not synthetic oil (it's still adequate oil, just not the best).

I do agree that there are benefits to synthetic oils. I run it in every gas engine I have. Large and small. On diesels though I still think it’s a waste of money. With Dino oil and the lubrication that the fuel contributes to the upper end of the engine there are not additional benefits to be gained to using synthetic oil in diesels....in my opinion.

NCC-1701A · 07-08-2020, 04:02 PM

From everything I'v read, T4, T5, and T6 can be mixed with no bad results, other than if it was filled with expensive synthetic, you might slightly dilute some of the benefits of a full synthetic by adding T4 to it. I'd get what you want of those three and add it. I'd almost bet that it was filled with T4 unless you specified the partial or full synthetic versions since those are more costly.

BTW... regarding Grindstone's comments on running cooler...on my last oil change I used T5 instead of T4. I had no idea that partial or full synthetics would run cooler, but last Sunday on the trip home, it was in the 90's and I had noticed that I was running from 5 to 10 degrees cooler for the ambient temps than I normally do. Perhaps the T5 is helping produce cooler running temps.

grindstone01 · 07-08-2020, 06:28 PM

Quote:

Originally Posted by NCC-1701A

BTW... regarding Grindstone's comments on running cooler...on my last oil change I used T5 instead of T4. I had no idea that partial or full synthetics would run cooler, but last Sunday on the trip home, it was in the 90's and I had noticed that I was running from 5 to 10 degrees cooler for the ambient temps than I normally do. Perhaps the T5 is helping produce cooler running temps.

Less heat generated means less friction inside your engine or transmission, which means there is less internal wear going on. The result is slightly better MPG and a slightly longer engine life expectancy.

bucks2 · 07-08-2020, 06:59 PM

It's pretty important to pay a little extra to extend the life of your diesel MH engine. Most are only rated for 500,000 miles or so using plain dino, so if you can pay $35.00 per oil change, ($5 more per gallon, 7 gallons per oil change, 1 oil change per year) and can extend the life of your engine by 50,000 miles it's well worth it. Once you get to that 500,000 mile mark you'll be cruising in style knowing you've done the right thing.

Oh, just a little more math for you. If you drive 10,000 miles per year it'll only take you 50 years on that chassis to get to that magic 500,000 mile mark. But if you change the oil at 5,000 miles that's 2 changes a year and $70 extra. If you drive 20,000 per year only 25 years. $35 per oil change times 100 changes is $3,500 extra you spent on oil.

Now ask yourself how many 25 year old motorhomes are still getting 20,000 miles per year with the same owner? I'm sure one will pop up and tell us who they are.

Perhaps clean oil to avoid premature failure is more important than the type of oil. And no one is stopping you from paying whatever you want for oil changes. Just know what you're doing when you decide what's right for you.

grindstone01 · 07-08-2020, 07:07 PM

According to Bucks2 math, he should consider just using water vs any kind of oil.

Keeping things in perspective, if someone can afford a diesel MH, then oil cost should not be a huge financial impact compared to fuel and other maint expense.

In all seriousness, I do agree with what buck2 is saying. Maint is about what you want out of your engine. My dad never changed oil in his car, but he got a new car every other year, so engine life did not matter to him! I always refused to buy his used vehicles, even though he offered me good deals on them.