Synthetic or Not?

[dougsram]

Cummins does not recommend extending drain intervals based on oil samples even if synthetic oil is used. To keep your warranty and or extended warranty you are required to change the oil and filter every six months or 7,500/15,000 (depending on your truck year) which ever comes first. Therefore, synthetic oil is a waste of money unless you need the 0 degree/cold starting ability. I buy whatever is on sale. Purchased Rosella T5 (synblend) yesterday from O'Reillys for $13.99 a gallon plus a $5 rebate per gallon from Shell. Purchase the best filters (FleetGuard LF16035 stratopores) from PureDieselPower for around $11 each if you buy a dozen. They usually have free shipping or 10% a few times a year. So a 11 qt. oil change with the best filter costs me about $36. Don't Nuc it, change your oil every six months and stock up on oil and filters ahead of time when they are on sale.

 

[dougsram]

Since the thread was about transmission fluid, I have a further recommendation. Don't pay six times more for Amsoil when you can purchase Castrol ATF+4 from Advanced Auto this month for $4 a quart. Just changed by transmission filters (purchase from Amazon $37 counting shipping), fluid, transfer case, and power steering with 13 quarts total. Total cost: $99. Since I towing my Airstream 90% of my miles, changed all the above at 38K miles. All the fluid was pristine, but cheap insurance for a long life for an expensive truck. Have never seen my transmission temp. above 150 towing up 11k mountains in Colorado; however, usually below 70 degrees ambient temp. that high in altitude.

 

[Newsa]

Cummins does not recommend extending drain intervals based on oil samples even if synthetic oil is used. To keep your warranty and or extended warranty you are required to change the oil and filter every six months or 7,500/15,000 (depending on your truck year) which ever comes first. Therefore, synthetic oil is a waste of money unless you need the 0 degree/cold starting ability. I buy whatever is on sale. Purchased Rosella T5 (synblend) yesterday from O'Reillys for $13.99 a gallon plus a $5 rebate per gallon from Shell. Purchase the best filters (FleetGuard LF16035 stratopores) from PureDieselPower for around $11 each if you buy a dozen. They usually have free shipping or 10% a few times a year. So a 11 qt. oil change with the best filter costs me about $36. Don't Nuc it, change your oil every six months and stock up on oil and filters ahead of time when they are on sale.

I don't extend drain intervals. But have benefitted from Amsoil's ability to withstand excessive heat when blowing a radiator hose and not being able to pull off the road immediately

 

[kthaxton]

I disagree about synthetic being a waste of money. It is simply superior. Lower pour point, higher flashpoint and its just slipperier etc. All of these are good things and worth every penny as far as I am concerned. Will it be obvious to you? not likely, but if you could do a side by side test over a long period, I'm sure you'd see the benefits.

 

[Newsa]

I disagree about synthetic being a waste of money. It is simply superior. Lower pour point, higher flashpoint and its just slipperier etc. All of these are good things and worth every penny as far as I am concerned. Will it be obvious to you? not likely, but if you could do a side by side test over a long period, I'm sure you'd see the benefits.

I was convinced of this when a harley-riding buddy of mine took some amsoil off of his harley dipstick and said "roll this around between your fingers."
It definately felt different than conventional oil. I was shocked to be able to feel the difference. It is slippery and spongy to the touch.

But amsoil wasn't listed as a top 5-8 diesel motor oil on any of the reviews (that I saw). Rotella, Royal Purple, Mobile 1 & Valvoline Blue are.

But I don’t think the reviews put as impottant weight on cold/cooler flow characteristics. They focused more on load-carrying capability. Which is why I was surprised to see non -synthetic Rotella T ranked higher than its synthetic Rotella T6 counterpart in at least one review.

I like the high temperature stability of synthetics & the peace of mind I get from running them in my cummins. Especially since the 6.7 doesn't have coolant passages between cylinders like the 5.9 did. I forget what they call this type of cooling. But it was mentioned on another thread in this forum.

I think the original purpose of the OP's post was not just about ATF4+. But also about oil

 

[Wayne M.]

If I put synthetic oil in like Amsoil, is it going to help reduce some Engine and Trans heat while towing up grades?

I've heard that's an inherent issue especially with the 68RFE Trans.

Have you been monitoring temps? What have you seen?
I think it's more important to have the proper fluid properties/ package in there than anything else. My '98 Durango/44RE has 120,000 hard NYC miles on it. I've owned it since 19k. I knew about the liability of this transmission (biggest complaint next to fuel mileage) so I resolved to drop the pan every 3 years and use ATF+4. Today there are no issues and shifts like new. transmission guys I know are impressed.

My story about real world Dino vs. syn goes like this.
In the late 80's I crewed on a dirt modified round track racecar. It had a Winters quick change rear. When we had to do a gear change, it required welding gloves because those gears were so hot. One day the owner brings a pail of syn gear oil. IIRC it was royal purple. Just by carrying the pail and hearing the oil splash around, I thought it was a joke. So we did the change out. Next race we did a gear change- WITH BARE HANDS. It was all over then!

 

[Cummins12V98]

Here are two VISUAL examples of 100% synthetic AMZ/OIL. Trans fluid and rear diff both have about 50K on them. This is from my 11 HO Dually that towed over half of it's live combined 28-29K 68RFE and 3.42 gears.

Trans fluid is Universal ATF and gear is Severe gear 75-110.

 

[gsbrockman]

My first four oil changes in my '14 were all 15W40 Rotella T. The last six have been Rotella T6 5W40. Since I hotshot, and run all over the place, I'd better have the 5W40 in my oil pan. Since my costs are generally almost all based on cents per mile, the extra ~ $8 per gallon ($24 per oil change) is not a huge deal breaker for me as I'm also of the opinion that the 5W40 T6 will give me a slight advantage in fuel economy, too.

With that being said.......I've sampled a few of my oil changes. The 15W40 Rotella has always had a slightly higher TBN than the 5W40 T6. I'm not losing any sleep over it.....and am running a lifetime average of 13,702 miles and 256 hours between oil changes.

 

[RSarvie]

I can respect your viewpoint, but look at it another way :
Near home, 5W40 Rotella T-6 Synthetic is $19.57/gal. 15W40 Rotella is $12.97/gal. That's $6.60/gal more.....or an additional $19.80 per oil change.

T-6 Rebate through the end of the year on up to 4 gals.
https://www.turbodieselregister.com/threads/254840-Rotella-T-6-5-Rebate-through-Dec-2016

 

[gsbrockman]

T-6 Rebate through the end of the year on up to 4 gals.
https://www.turbodieselregister.com/threads/254840-Rotella-T-6-5-Rebate-through-Dec-2016

Thank you !!!

 

[Bug Out]

I use synthetic as my oil change intervals have virtually doubled from my 2005 5.9. I used to change the oil in my 5.9 every 5k. Now the 2013 calls for a change at 10k plus. I usually change it at 9500K (recommended by blackstone after a sample sent) which puts my oil change cost at about the same as dino shell 15/40 @5k vs Shell 5/40 at 10K.(give or take a few pennies...)

With my 5.9 in the 1998 3500, I noticed a MAJOR difference between Shell dino 15/40 and Shell synthetic 5/40. Fuel economy was up 1.5 MPG, engine noise was down just a tad. However I did notice oil seepage around several areas not previously seeping. I changed back to 15/40 dino. That particular test was done from N/California to Ft.Sill Oklahoma and back. My concern was it was over 5K in distance and I did not want to get involved in a oil change so I tried synthetic 5/40 for that trip alone.

 

[Dogpatch]

I just did my first oil change at 15,000 kms (9300 miles). My truck was in for a couple of other small things (dash squeak) so I decided to get my oil changed at the same time. My gauge on the EVIC said I still had 40% life left. To me, I wanted to have my first oil change early. I plan on doing oil changes early all the time like every 10,000.
The Stealership told me my oil looked barely used. It was stock oil not synthetic. I had them put the recommended regular oil in on this change. I will likely buy Synthetic and have them use it next change as I get a fairly good price on it at $75 for 3 gals CAD. It's $29.99 labour to change.

Do I need a different oil filter for synthetic?

 

[Newsa]

Do I need a different oil filter for synthetic?

Same oil filter as conventional oil when switching to synthetic

 

[RSarvie]

.....The Stealership told me my oil looked barely used. It was stock oil not synthetic....

I thought they came stock with synthetic???

 

[Dogpatch]

I thought they came stock with synthetic???

That's what I thought too given the longevity between oil changes, but I was told no by the Stealership.

It amazes me that standard oil will give that many miles. Of course, there is almost 3 gallons so that might explain it.

 

[Cummins12V98]

That's what I thought too given the longevity between oil changes, but I was told no by the Stealership.

It amazes me that standard oil will give that many miles. Of course, there is almost 3 gallons so that might explain it.

Your dealership if full of Barbara Streisand!!! The 6.7 Cummins engine comes from the factory with synthetic oil! I would go back and demand they put synthetic in it at no charge!

 

[mpaulson]

That's what I thought too given the longevity between oil changes, but I was told no by the Stealership.

It amazes me that standard oil will give that many miles. Of course, there is almost 3 gallons so that might explain it.

Your stealership is clueless. All Cummins, at least the 2013's and up, come from the factory with Syn 5-40 because they don't know if the engine will end up in Death Valley heat or in the Artic Circle winter.

 

[Dogpatch]

You can bet I'll be calling as soon as they're open after the weekend!

 

[Dogpatch]

Has anyone got any documentation that the 2015 Ram 6.7 CTD comes from the factory with Synthetic oil?

I'm going to see them tomorrow about what they put in for my oil change Last Thursday. It would be nice to know. Ive tried googling and can't come up with anything!

 

[jhenderson]

The original fill from Cummins is synthetic. Not knowing where or when the engine will be put in service they fill with Premium Blue Synthetic at the factory. Sorry for the piling on but I didn't see the other posts when I started to answer.