ok people hit me up with some good answers, i have a 2003 ram with 37,500 miles on the cummins and wanna do the first oil change since ive owned it, i do not tow anything, and sometimes make short 10 mile trips a day, should i use dino oil or syn?? i live in central virginia were it i now about 40 degrees in the day, 20 at night average, also give me the best brands of oil to use in dino and syn

 

Well, here's my vote:

Chevron Delo 400 15w/40 (dino)
Mobil 1 Truck & SUV 5w/40 (real Synth)...also known as Mobil 1 Delvac
Scheaffer's Supreme 7000 15/w40 (blended)

But you can't go wrong with any of the licensed API CI-4 or CI-4 Plus rated oils.

Check out www.bobstheoilguy.com for everything you ever wanted to know about lubrication.

 

I used Rotella dino since the truck was new. Now that they came out w/ the synthetic version I have been using that. The only bad thing is that the "Smell" is back with every oil change.......

 

Please do a search on this site. You'll have hours of reading to catch up on.

 

Ask yourself this: Do I want clean oil in my engine every 3,000 miles? If the answer is yes, go with dino oil.........it would be a waste, and far too expensive to go with synthetic and change it out every 3K.

Personally, I do not like leaving oil in my engine past 3K.....it breaks down and gets dirty.....I like the idea of clean fresh oil flowing through it's veins.

Of course, you can hook up a dual by-pass filter, go with synthetic and change out evey 10 or 12K or possibly even longer......I just could never talk myself into that.

I use Delo, buy it at COSTCO and like it very much.

 

As I recall Cummins states that you should wait until 20k miles befre using a synthetic, can't extend oil change intervals because you're using synthetic, and can't extend because you're using a bypass filter or doing used oil analysis. The 100k mile warranty on the engine seems like a good thing, so abiding by factory requirements seems reasonable. Because of that I found synthetic to expensive to dump at OEM oil change intervals, so I use a homemade synthetic blend of 4 qts Mobil 1 Truck & SUV, an excellent 5W-40 synthetic, and 2 gal of Delvac 1300 15W-40. I even use a blend in both cars; 2 qts Mobil 1 T&S with Mobil 10W-30 dino, as it seems to run quieter and cleans better.

 

Interesting blend...

As far as changing the oil at 3K, with a filter change too I presume, seems a little excessive since the maual says 7500 (schedule B), 15000 (schedule A) for oil/filter changes. If the oil/filter capacity was only 6 or 8 quarts, then I would be concerned about the factory schedule, but I'm not since it holds 3 gallons of oil. Plus, with all the UOA's I've seen, 7,500 looks a little early. Looks like the vast majority can run with 10,000 mile intervals no problem. It's your money so spend it how ever you like. You shouldn't have any problem selling it with that maintanance schedule (if you have all the reciepts).

A lot of people are brain washed by the 3K oil/filter change schedule the lube centers so aggressively advertised for so many years. Many can't understand how oil can work past 3K (most didn't 25 years ago). Of course, if a lube shop is using Fram or Pennzoil oil filters, I wouldn't trust those for more than 3K, if at all, either.

 

These trucks hold alot more oil than your Honda or Toyota, 3 gallons of oil will have no problems going 5-8 thousand miles with a good filter, Heck, I just drove almost three thousand miles last week down around southern California and back in a little over a week, should I change the oil now

 

Doubledodge2003 synthetic doesn't 'break down and get dirty' nearly as quickly as dino oil. A safe interval would be 5000 miles on dino or 10,000 miles on synthetic. Both must be a quality CI-4 rated diesel oil. 2003-2004 models are extremely clean burning and easy on oil. After 10,000 miles including a lot of towing my oil analysis came back with the oil nearly new. Gotta love Delvac 1!

 

That's the whole idea about synthetic....it doesn't break down as quickly as dino thus you can run it longer.

After 3K, my oil is looking a bit dirty......I will continue to change every 3K as always. I have done this with all of my vehicles including my motorcycle......gives me peace of mind knowing I have fresh, clean oil running through the vitals of the engine. I am well aware what the manual states, but I have raised the standards....cheap insurance IMHO.

 

With diesels it seems to be the soot content that causes the most problems with oil, which as I recall is the reason for the CI-4 spec. I have a 2003 with a CARB engine, and from what I understand the reason for the 3750 mile oil change interval is the soot level as it's designed to run cooler for lower nitrogen oxide byproducts. I don't think that a synthetic has a higher soot carrying capacity, which is probably why Cummins says that you can't extend oil change intervals because you're using a synthetic. If you look over papers on wear in diesels it's surprising how much wear is attributed to soot, as it's fine stuff, much smaller than oil film thickness.

 

I'm not sure specifically about the CA package, but 03-04 diesels make so little soot it's not a factor. If you look over the many oil analysis reports for these years, it becomes obvious just how easy these trucks are on oil.

 

I use the synthetic, and the best reason is more for the bearings for the turbo. If I forget to sit and let the truck cool before turning her off I know the Delvac 1 that I have in the engine will handle the heat...and the dino oil would cook. I do not tow like some of you guys, so it is not a big deal for me. I changed to the Delvac at 20K, and will now split the difference of the oil changes (between the 7500 and 15000, and will do so at 12,500 miles). I run the Amsoil oil filters, so I am good to go.

 

Angleiron you might want to check on the Amsoil filters. The SDF oil filters are only good for 7k miles on the Cummins or 6 months. You have to change them, and then top off the oil.

From the Amsoil product page: http://www.amsoil.com/storefront/sdf.aspx

" In diesel-fueled large truck engines, change the filter(s) at the engine manufacturer's recommended oil change interval. In diesel-fueled light trucks, including pickups and vans, change the filter at 7,000-mile or six-month intervals."