Synthetic or Dino oil?

[RVTRKN]

I know my truck is a 3rd Gen, but I had a weird question at a Dealer in Las Vegas yesterday. The question was, "do you want synthetic oil with your oil change"? Apparantly the 2018 models are now factory filled with synthetic oil. I was taken aback to the question because I have never have been asked this at a Dealer, in fact my truck oil has ONLY been changed by Dealerships. I have no idea what brand or what the specs of the oil is that has been filled with, in my truck. I'll assume that they used the proper oil for the 2007 6.7 CTD, being their the experts.

Sooooo, the question is now, should I convert to syntechtic oil after running Dino oil for 75K miles, which will be at 80K when its due? I converted my Harley to Synthetic from day 1, with 2 miles on the Odometer. Would it be disadvantageous for me to convert at this point?

 

[lpennock]

If you are only running 5K miles between changes there is no real advantage to switching.
The exception being if you are going through temperature extremes. I.E. Sub zero weather then travelling to 100 degree weather where you would be out of the recommend operating range for the weight dino oil you are using. Synthetic can be had in 5w50 which will cover all the temp ranges.

 

[Cummins2014]

If you are only running 5K miles between changes there is no real advantage to switching.
The exception being if you are going through temperature extremes. I.E. Sub zero weather then travelling to 100 degree weather where you would be out of the recommend operating range for the weight dino oil you are using. Synthetic can be had in 5w50 which will cover all the temp ranges.

If you read the manual, its 5W-40 Synthetic if you will be below 0 degrees, above that 15W-40 dino is okay, but both are okay above 0 degrees.

 

[lpennock]

If you read the manual, its 5W-40 Synthetic if you will be below 0 degrees, above that 15W-40 dino is okay, but both are okay above 0 degrees.

You're correct. I was thinking of one of my other vehicles that listed 3 different grades depending on temp range.

 

[Newsa]

The dealer might just be trying to sell you an oil change with more mark-up in the price? If they hooked it up to their Witech and see it is doing more than the usual number of active regens, they might think that you could benefit from synthetic. More than the usual number of regens could cause mild fuel dilution which synthetic can deal with better. But i doubt they did that.

I use mostly synthetic blends or synthetics. I don't have to.... I choose to.

 

[RVTRKN]

The dealer might just be trying to sell you an oil change with more mark-up in the price? If they hooked it up to their Witech and see it is doing more than the usual number of active regens, they might think that you could benefit from synthetic. More than the usual number of regens could cause mild fuel dilution which synthetic can deal with better. But i doubt they did that.

I use mostly synthetic blends or synthetics. I don't have to.... I choose to.

Interesting thought about regen frequency, being mine is a C&C with a slightly better smog setup, I never thought about the influence of regen on Dino vrs Synthetic. Will Synthetic help in this issue, now that I have EFILive setup, it seems to go into regen more frequently? It's not that much more with the cost of synthetic oil to change, but what about a engine being used Dino, will it work?

 

[Cummins12V98]

6.7 has came with Synthetic since 2013 and maybe longer??? You had good reason to run it in your Harley as I do. I run the AMZ/OIL 20-50 in my Harley.

I run Signature Series AMZ/OIL 15-40 in my 15. Never in cold climate but I would not change as it's good down to -40 and their 5-40 is good down to -43. So IMHO the 5-40 is a waste.

Run what i have mentioned and go with your full change interval. I did so with my 11 HO 6.7 with great test reports.

 

[gsbrockman]

6.7 has came with Synthetic since 2013 and maybe longer??? You had good reason to run it in your Harley as I do. I run the AMZ/OIL 20-50 in my Harley.

I run Signature Series AMZ/OIL 15-40 in my 15. Never in cold climate but I would not change as it's good down to -40 and their 5-40 is good down to -43. So IMHO the 5-40 is a waste.

Run what i have mentioned and go with your full change interval. I did so with my 11 HO 6.7 with great test reports.

What exactly was your OCI’s on the 2011???

 

[Newsa]

Interesting thought about regen frequency, being mine is a C&C with a slightly better smog setup, I never thought about the influence of regen on Dino vrs Synthetic. Will Synthetic help in this issue, now that I have EFILive setup, it seems to go into regen more frequently? It's not that much more with the cost of synthetic oil to change, but what about a engine being used Dino, will it work?

3rd gens are prone to more fuel dilution (if I remember correctly.). My opinion is that if you are doing 5000 mile oil changes, ( on a recommended 7500 mile OEM OCI) you will benefit from a synthetic. Reports are that synthetics allow the fuel to evaporate out of the oil before it permanently mixes with and changes/reduces the viscosity of the oil.

You don't want the viscosity of the oil when hot to drop below 30 weight because you may not have enough film strength to prevent quicker wear?

A series of UOA's would give you a more complete picture of how your engine is behaving with EFLive. Or if the cost of synthetic is not much more at the dealer, it would definitely be somerhing to consider IMO.

 

[Newsa]

Here is a quality synthetic at a reasonable price
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/263573221348

 

[nukegm]

go synthetic. its better all the way around. and to go back and forth over 50 bucks or so when your cummins replacement might cost 10 grand is nuts. also, make sure you use a quality filter that can go the distance. cheers comrades!

 

[Cummins12V98]

What exactly was your OCI’s on the 2011???

All my reports came back less than 0.5% and NEVER made any oil.

Oil used AMZ/OIL 15-40 Signature Series along with FleetGuard Stratapore filter.

 

[JR]

All my reports came back less than 0.5% and NEVER made any oil.



View attachment 110563

I can say the same thing....with conventional oils.

Synthetic makes sense if dealing with sub zero temps and to a lesser extent extreme high temps but the vast majority of the time conventional is MORE than adequate. Particularly in a truck that has its oil changed well before the factory recommended intervals, and even more so with the new CK4 formula which is hands down the best and most robust oil spec yet.

Under the CJ4 spec I ran synthetic, I studied the CK4 spec carefully when it was released and am more than comfortable running it in conventional flavor.

 

[Cummins12V98]

The less than 0.5% has NOTHING to do with the oil you use, just a statement showing if you drive your truck like a truck it should not have fuel dillution. I ran full 7,500 mile with my 11 and now with my 15 and they say to go longer if I want.

 

[RVTRKN]

I checked for fuel in oil at @12K miles in 08 and it was so negligent I never worried again. But my truck can and will go into regen when towing heavy, even climbing grades at 23K GCW with 1200* EGT. I have allways changed my oil at 5K intervals, except the 2014 CTD company truck, that the company owned. The owner bought into the coolaid that 12,500K miles, and more if the computor showed the oil was OK. I was never asked if I wanted synthetic when at a dealer, even with the 2014, so I was wondering if there is any benefit with synthetic on an engine that runs cool, when asked again. my 07 never is run in extreme temps, although now that I'm located in Vegas, and I wonder if I should go to synthetic? I will change the oil at 5K, regardless of what oil I chose.

 

[JR]

If you have any doubts a UOA will answer your question, personally I think you will find what you have been using is more than adequate. I go 15k on conventional with excellent UOA's. It is very capable of adequate protection despite what some would have you believe.

 

[Cummins12V98]

I checked for fuel in oil at @12K miles in 08 and it was so negligent I never worried again. But my truck can and will go into regen when towing heavy, even climbing grades at 23K GCW with 1200* EGT. I have allways changed my oil at 5K intervals, except the 2014 CTD company truck, that the company owned. The owner bought into the coolaid that 12,500K miles, and more if the computor showed the oil was OK. I was never asked if I wanted synthetic when at a dealer, even with the 2014, so I was wondering if there is any benefit with synthetic on an engine that runs cool, when asked again. my 07 never is run in extreme temps, although now that I'm located in Vegas, and I wonder if I should go to synthetic? I will change the oil at 5K, regardless of what oil I chose.

Guess I need to post my 15k oil change reports.

 

[NIsaacs]

RV, as an old timer here, don't you know better than to start an oil thread? With 5k changes I would stay with what you been using. Super duper oils and filters, extended drains, UOA's,... meh... I use what's on sale and Napa filters, 326k on the '91, 326k on the '01 and no clue on the old Ford, same stuff I use in all my off highway equipment.

With only 80k miles on a 12 year old truck, oil changes are not costing you much. I would use what makes you sleep well.

 

[Cummins12V98]

Here are all my reports with 15k changes using AMZ/OIL 15-40 Signature series and FleetGuard Stratapore. Towing 33-35k combined for just under 1/2 the miles.

 

[Cummins2014]

go synthetic. its better all the way around. and to go back and forth over 50 bucks or so when your cummins replacement might cost 10 grand is nuts. also, make sure you use a quality filter that can go the distance. cheers comrades!

Seriously, go synthetics to prevent engine replacement. How about recommended oil ,and filters at the proper intervals . Dino or synthetic .This synthetic thing is nuts. Been running plain old Rotella T4 for over 20 years now .