"Diesel" oil

[zachmac]

I will first admit that a search got me previous threads that said yeah, go for it. But, just to check:

Getting ready to do an oil change and it is very hot here in SC and never goes anywhere near freezing and the Fiat manual says run 15-40 W. Run to the auto parts store and the only 15-40W is "diesel" oil. Quick internet search says no problem as long as the weight is okay for your car and you'll get added detergent and zinc to boot.

So, anyone running "Diesel" oil and if yes had any issues. I'm not running any emmision equipment so the zinc shouldn't be an issue.

BTW, it is 1/2 the cost of "regular" oil so why the heck not?

Lastly, DieselSpider please resist the urge to tell me you do it all the time!

[NSFIAT]

I've been using Shell Rotella for 4 years now without issue - 15-40!

[PhillySpider]

I've been using Shell Rotella for 4 years now without issue - 15-40!

^^^this. Don't know what the PO ran, but bought the car and immediately flushed all fluids. Research at that time told me to go with Rotella as well.

[joelittel]

I use Shell Rotella as well

[zachmac]

Thanks for all the quick replies. Rotella is is.

[Jimb]

Another vote for Shell Rotella

Jim

[johndemar]

Shell has reformulated their oil and I don't believe it's as preferable as it once was. I know there is a post here about it if you search for it. I'm going to need a change by fall and will need to research it again as well.

[DieselSpider]

Yes I use it sometimes in my gasoline powered lawn equipment and many use it in their air cooled motorcycles and scooters that do not have a wet clutch. As long as it meets or exceeds the API certification required by the engines manufacturer you should be good. Some people also like to use oils rated for natural or lp gas powered engines in their gasoline engines that are not used often due to the way it handles condensation better.

[SP3]

I've been using Shell Rotella for 4 years now without issue - 15-40!

Hell, I use it in my Ducatis. Even if it's been 'reformulated', it still meets the requirements of its stated viscosity and will have more 'good stuff' in it than a like-weight 'gas' oil.

[Odoyle]

I have been running 30 wt Castrol with a CamShield zinc additive during the summer months in CA.

[aj81spider]

I buy my oil at NAPA and sometimes the only 15W-40 they have is labeled diesel. I've used it with no problem on my '74.

[njoconnor]

Shell has reformulated their oil and I don't believe it's as preferable as it once was. I know there is a post here about it if you search for it. I'm going to need a change by fall and will need to research it again as well.

Kilrwail (Peter B) commented on this during the FFO Parking Lot gathering a week ago. He mentioned the prior thread (http://www.fiatspider.com/f15/viewtopic ... it=Rotella), and the change in Rotella from CJ to CK formulation, with a reduction in zinc. As it happens, I'd just purchased some Rotella prior to FFO, and when I got home, checked it.....CK. Arf.

So, I also have a pint of Lucas Oil ZDDP, and I noticed on Mark's site that Camshield is used in amounts of 1.5-2 oz per oil change in the Spider. Would adding the 2oz of the ZDDP I have to the CK mitigate the effects until I can locate (and buy up) any remaining stocks of CJ?

Thanks

Neil

[DUCeditor]

If your engine is still tight I suppose the originally recommended 15-40 is still a good idea.

My `77 -- a seasonal runner -- has been run on the commonly available 20w50 Castrol GTX for the thirty years I've owned it.

-don

[RRoller123]

An interesting discussion on one of the hot rod forums that I occasionally read. The discussed premise is that the reduction in zinc was replaced by an increase or inclusion of other, more environmentally safe wear reduction additives, and that the whole issue is a red herring. It kind of makes sense, as the oils should be backwards compatible. It seems unlikely that they are going to issue a new formula that will cause any flat tappet damage, without a warning.

Also, the hot rod guys on this particular forum were told directly by Shell Customer Support in an email that there was no issue. Not sure I am willing to bet the house on it, so I just went out and bought a few of gallons of the old CJ stuff, enough for a couple of years of changes. I change twice a year regardless of mileage.

I put in a written request to the Shell Rotella business group to clarify the CJ to CK change, and its effect on flat tappet OHC/V engines. Will let you know what they say back as soon as they say it back.

Pete

[RRoller123]

Here is what I wrote to Shell Rotella Business group:

"Hi. I run a 1980 Fiat Spider, and myself and hundreds of other enthusiasts on our forum (www.fiatspider.com) use Shell Rotella Diesel 15W-40 engine oil for the high zinc content, to protect our flat tappet cams and valve train. (We use this diesel oil in our twin cam OHC/V flat tappet gasoline engines). We are aware that there is a spec change from CJ to CK, either here already or coming, that reduces the zinc content, and are understandably concerned about what this may do to our flat tappet cams. Can you provide any info on this potential problem of using the new CK formulation in our older cars? Thank you for your assistance!"

Here is what they wrote back:

"Hi Peter, thanks for reaching out! The new CK-4 Rotella products, which were rolled out December 2016, are suitable for flat-tappet engines that benefit from higher Zinc and Phosphorus levels where catalytic converter compatibility is not a concern. Hope this helps!"