Hey everyone!
New here and had some questions. I use full synthetic in my gas trucks and would like to run synthetics in my diesel truck (crank case/rear ends etc) So who has the best oils? I haven't seen much in the way of synthetics for diesels in the local shops.
Topper

 

Well, that's going to open a big ol' can of worms.

Here's my opinion - the Cummins will outlast the rest of the truck running any name brand diesel rated dino oil. There's no sense spending the extra money (double or triple) for synthetic unless you live where it's regularly below 10 degrees in the winter and you can't always plug in.

In the trans and rears I am all for synthetics. I have Redline MTL in the trans and Mobil 1 in the rear.

If you really want to use synthetic in the engine, the best deal going is Mobil 1 Truck & SUV in 5 qt jugs at Wal-Mart. It's relabeled Delvac 1, the best synthetic diesel oil out there.

 

Thanks for the reply,
The reason I run synthetics now is because of the miles that I drive. I drive to a plant in Kingston 2 days a week (102 miles each way) and To NYC 3 days a week(213miles each way) and you never know were I am the next two days. Last week I drove 1900 miles. The little Dodge Dakota that I've been driving has 150,000 on it and I got it in OCT. of 2003. I don't like have to change my oil every two weeks. I need to extend my time between oil changes as long as I can.
Topper

 

10k on dino oil is no problem. The Cummins is very easy on oil. There isn't a high pressure oil pump like a Powerstroke, and the engine has a water cooled oil cooler. The oil gets dirty before it deteriorates. Remember that you have 3 gallons of oil in there, it takes a good bit of driving to load it up with crud.

Synthetic still gets dirty, so unless you plan to add a bypass filter system you don't stand to gain much from synthetic.

 

As far as the BEST it would have to be amsoil.

 

Well, that piont is debatable....

Mobile makes a great product and is very hard to beat.

 

OK worms - the can is now officially open!

 

fishing anyone?


he he he he he he I tend to agree that mobil 1, and delo, and rotella are the best oils out there.. but what dave says is right... i couldnt have said anything better...

Tx

 

You make a valid point. From what I have read. Mobile 1 is second to Amsoil out of yhe synthetics. I still think you might as well pay a bit more for the amsoil.

 

and I did it again....sorry

 

Group III synthetics are so close to PAO based synthetics in performance it's a tossup. I prefer to buy over the counter and use API "certified" and Chrysler approved oil so Mobil-1 or Valvoline Synthetics suit me fine. Valvoline Premium Blue 2000 would be my first choice for synthetic for the Cummins. Premium Blue is Cummins fomula contracted and brewed by Valvoline. I'm running Valvoline synthetic in our Durango and Ram gassers now. Roll yer britches up! I'm getting 10% better mileage, they run 15*F cooler, 15 more hp, it rides better, the radio sounds clearer, the windshield wipers don't chatter and the headlights are brighter! Yep... There are some mighty tall claims out there.

 

My mileage went up so drastically when I switched to synthetic oils that I have to stop at the diesel pump and actually allow some of the fuel the engine makes to flow back into the stations tank, thereby reimbursing me when I drive.

I run synthetic in every reservoir I can on my trucks (since my first diesel in 89) and I can't really tell you it is any better than dino oil at all. I run the dual bypass system and am running 25000 miles even pushing 400 horse power (or more). I can tell you that at 154000 miles, I burnt up number six piston (see my photo album) pulling 21000 pounds up Afton Mountain (no EGT gauge) and drove it near 500 miles with the melted piston hammering like someone was in there with a sledge trying to get out. When Scheid Diesel opened it up to repair it, there was no scoring in the cylinder at all and they didn't even have to bore the engine when they put new pistons and rings (with a lot of other stuff). I can't tell you whether synthetic helped keep from destroying the cylinder or not but I personally believe it did. They also said that my engine was the cleanest they had ever seen for that mileage.

Yes I am a dealer and no I do not push the product. I use it myself and believe in it so take this for what it's worth. I also believe that properly serviced dino oils will give you the same mileage and I'm sure some of the higher mileage truck owners will verify. I just hate trying to dispose of three gallons of oil every 5000 miles.

 

My $0.10. I like Amsoil. Saw an improvement in temperature and mileage over the Mobil 1 I switched from.

I had to do the plenum gasket on my '98. Got out everything needed for the job including a ton of rags to clean everything up. We got the intake off and wow. Everything was so clean it was unreal. I need to figure out what my tranny holds because the Amsoil juice is gonna find it's way there too!

And I'm not a dealer - just a preferred customer or whatever they want to call it - so I can get a better deal.

 

I prefer Mobil 1 Truck & SUV (or Delvac 1) simply because it is easier to get. I can get 12 quarts off the shelves of Walmart for about $55. Amsoil is impossible to get off the shelf locally and by the time you pay for shipping it's significantly more expensive than the Mobil 1.

I run Mobil 1 in my engine and in the differential. I need to change the tranny fluid, but I haven't decided what I want to use in it yet.

 

Hoss,

There should be a ton of dealers locally in your area that'll deliver to your doorstep for free. Unless you're completely out in the sticks.

I didn't pay that much more for Amsoil Syn oil and a filter. $58.80 for 2.5 US gal/9.5L jug of 15w40 Diesel/Marine and $13.55 for an oil filter. That's right off my last receipt - had to dig it out. Cdn dollars mind you. I think I'm going to start buying in bigger containers too - save way more than buying by the 2.5 gal jug. So, in the course of a year, it'll be cheaper for me than buying Mobil 1 that I used in the past if buying by the 5 gal Amsoil container (I think that's what the next larger size is). I think it was around $70.00 for a case of 10w30 (12L) at Walmart for Mobil 1.

All I do, when I have errands running past the warehouse or coming back into the city from work, is call them and give my preferred customer # and order. When I get there, my stuff is sitting on the counter ready. I give the nice lady my money, and I'm gone in less than 5 min.

BTW, nice ladies like taking a man's money - makes my detour way fast.