Synthetic Oil

[Ereynolds72]

I just changed my oil for the first time. The change oil indicating light came on at just under 5k miles. Normal interval according to the book would have been 6k anyway. I used the Shell Rotella 15W-40. I was wondering if switching to synthetic was worth the extra cost? Does it extend the change interval?

The oil that came out was very black and "sooty-looking". I hate to spend the extra money for synthetic if I'll still be changing every 5-6k miles.

 

[PFranzese]

Normal interval according to the book would have been 6k anyway.

Does the '10 model have a different interval in the manual than the '09? Mine shows 7500 or indicator light, which ever comes first.

 

[HBarlow]

I just changed my oil for the first time. The change oil indicating light came on at just under 5k miles. Normal interval according to the book would have been 6k anyway. I used the Shell Rotella 15W-40. I was wondering if switching to synthetic was worth the extra cost? Does it extend the change interval?
The oil that came out was very black and "sooty-looking". I hate to spend the extra money for synthetic if I'll still be changing every 5-6k miles.

The synthetic oil question has been asked, answered, and discussed, perhaps hundreds of times, here in the TDR website. The answer is always the same.

You can use synthetic oil if you choose to but Cummins and the Dodge owner's manual in your glove compartment plainly state that use of synthetic oil WILL NOT extend the service interval.

The reason is because it is not a matter of whether conventional engine oil or synthetic oil will break down after 5k, 10k, 15, or 20k miles, it is the acids and contaminants the oil picks up and holds in suspension that requires the routine change. I have always used 10k service intervals, some use fancy filtration and never change the oil, just change the filters and replace the lost oil.

Also, on the ISB6. 7 pickup engines, the oil service interval indicator does not know whether you are using conventional or synthetic oil and has no way to determine the difference.

Use of sythetic oil is strongly preferred and defended by some but all it will do is increase your operating costs.

I've never used anything but ordinary Rotella in my previous two Ram-Cummins engines and now Valvoline in my ISB6. 7.

 

[RobertHiltz]

Synthetic oil is better if you have to do cold starts with out a block heater. In GA you will not be exposed to 20 to 60 below temps so it should not be a concern. Changing oil at 3000 to 5000 mile increments with any oil that meets the required specs is probably better than using the most expensive synthetic and running high mileage between changes.

 

[Ereynolds72]

Does the '10 model have a different interval in the manual than the '09? Mine shows 7500 or indicator light, which ever comes first.

Yes. Interval indicated in my owner's manual is 6,000 miles.

 

[PFranzese]

Thats interesting considering the engine has not changed. Any of the techs know why it has been reduced to 6k?

 

[gsbrockman]

Yes. Interval indicated in my owner's manual is 6,000 miles.

I *think* the value of my 2007. 5 just went up a tad. :-laf

 

[jelag]

Over the past 15 years we've owned many trucks. . which we keep for 500K miles before we trade... we use standard oil, filters at 10 K change intervals... and to date with our 04 at over 300K, our 04. 5 at 200K, and so on up to our 08 5500 with 110K miles we've had no problems with the standard oil and the 10K change... we've yet to have any issue with any of the engines...

Just my thoughts.....

 

[EricM]

I'll add another wrinkle to his discussion. My '09 owner's manual specifically requires use of synthetic when operating at or below zero degrees, which is common in our area. This was not the case with my '03. I used 5w40 synthetic in my last change back in December due to this requirement. I realize the interval will not be extended and it's probably overkill, but I didn't want warranty issues. It was an easy decision, as in keep the warranty on a $50k truck vs an additional $50. 00 for an oil change.

 

[Garlic]

I have had the oil changed at the dealer for $49. 95 and it appears all they do is drop and refill. Valvoline has been servicing my other trucks for many years now and I decided to run the 07. 5 through. Rotella was $89. 00 for the basic oil change, but the Valvoline Premium Blue synthetic 5w-40 (CJ-4) was $99. 00 if I brought my own filter in (They deduct $3. 00, big whoop) I felt it was a no brainer, I sample the oil at every change to monitor wear and fuel contamination for $22. 50. So far at 5K intervals the fuel loading and insolubels (spl) (Soot and heavy junk) have been with in limits, for me the peace of mind to watch them do the service is worth the money (Just my two bits worth).

 

[daverobb]

I think that this issue comes down to two or three questions. 1. How long are you intending to keep the truck and how many miles will be wracked up in that time? 2. How cold does it get in your area?

If the ownership is to be short term, with average or below accumulated miles, then I don't think that Synthetics are worth the extra $$$$. Pick a good non synthetic based oil that is CJ-4 rated and do regular changes. If ownership is long term synthetics are an investment.

Synthetics flow better in cold weather, reducing start up wear.