Not a heated oil thread. Can I use...

[Caseyjones955]

Napa Full Synthetic Motor Oil 15/50 Energy conserving SM rated?

87 300SDL, PO stated he was using synthetic and I have read here that it makes it run quieter. Car runs well, unknown milage but likely pretty high.

I ask about this oil because I have 2 cases of it and the Napa guy says its cool for Diesel but no C rating on the bottle concerns me. Im reluctant and fighting the urge to just use Rotella, the same crap my truck happily thrives on. So I ask the following without causing a heated debate over correct brands and wt.

Does my 603 really bennifet from synthetic oil considering I dont mind changing every 3k or so, can I expect it to run smoother and quieter with snythetic?


If synthetic IS bennificial is SM rated ok, should I be looking for the CD rating or something else?

The threads I have read so far are avid and contain endorsements for specific brands and wts, usually in sharp contrast to other endorsements in the same thread. I only want to know if a full synthetic is really bennificial and if so is what I already have proper (SM?).

Thank you.

[rrgrassi]

I would use only a diesel rated oil in a diesel engine, conventional or synthetic.

[Cr from Texas]

My 2 cents worth would be to use the C rated regarless of synthetic or dino. That rating has to do in part with dispersing combustion by products from diesel fuel.

[pawoSD]

Use a diesel rated oil. There are so many to choose from, both dino and synthetic, why consider doing anything else?

Being in South Dakota you might really want to consider using a synthetic 5w40 diesel oil....it is much better for the engine on those real cold starts....it flows much better. And in doing so, allows the engine to start easier.

[Diesel911]

This is my experience:
I bought the Volvo Diesel back in 1992 and overhauled the short block. Up until the beginning of this 2009 I used regular gasser Oil it it.

I had 3 gas cars and 1 Diesel and wanted to use 1 grade and type of Oil on all of them; and I did. 20-50wt dino is what I used.

I also change my Oil about every 6-8 months and am a low milage driver.
Also, for the 1st year I owned it the Mercedes got the gasser Oil.

This year I switched to Rotella T for the Diesels and I only have 1 gasser.
Also the Volvo does no soot up the Oil like the Mercedes does.

I would have no problem using up a 2 cases of good quality Oil.

Maybe you could just save it for winter use.

Some members have mentioned that the synthetic for Diesels quieted there valve lifter tick in their Hydraulic Valve Lifters but not all said it worked for them.

[ah-kay]

If you are changing every 3K miles then dino is OK. Synthetic would become expensive as diesel takes more oil then gasser. I used to use any cheap oil and change it every 3K but now I use C rated oil from Costco. That was before I realized diesel car needs to use C rated oil as I have never driven one before. I drove the 300D & 300SDL for over 20K before I read it from this forum. It does not seem to have done any damage to the cars. Sometimes I question whether C rated is absolutely necessary if oil change is done every 3K. Any oil is better than no oil, I suppose.

[Caseyjones955]

This is what I thought, that guy did his best to convince me that this oil was great for a diesel, I didnt buy it and luckily I found the reciept for it.

Point well taken, C rated oil it will be.

Im leaning heavily towards using the Dino Rotella, would there be any problem going back to dino now since there is already snyth in the crankcase? I dont forsee any issues but anything I should do or watch out for?

I ask because I have only ever used synthetic oils on motorcycles (gearboxes do seem to love it), never in cars or trucks so switching back and forth is completely foreign to me.