New Duramax Oil Advice

[coyotekid]

I recently purchased an '04 Chevy with the Duramax diesel in it. I want to treat it right, which is why I'm asking questions here. Forgive me if this is a little long, but I'm anxious to learn!

1. A local dealer swears up and down that these engines come from the factory with Mobil 1 Delvac 5-40 full synthetic oil. While it looks like an excellent oil for this application, I think they're totally full of BS! What do these engines really come from the factory with?

2. I plan to run petroleum (dino) oil during the break-in process, as suggested by most of the members here. I have a case of Delo 400 15-40 laying around that I'd like to use. It meets the CH-4 specified in my owner's manual. With it, I'm planning to use the factory spec AC Delco oil filter. Would this be a good combo for the first 10,000 miles?

3. After the first 10,000 miles (if that's long enough) I'm planning to switch to a full synthetic and a bypass filtration system. I'd like to use Amsoil, but they don't offer a 5-40 designed for this type of engine. My manual specifically warns against using anything other than 5-40 (in colder climates) or 15-40. This leads me to the AME 15-40, but I live in Montana and see lots of cold weather at any time of the year. For example, it's not uncommon for me to make a 30 degree start-up in July! For this reason, I'd like to use just one oil grade year round if it will offer good protection for the engine.

As you can see, I'm lost in the maze of diesel oils! Please lend me some advice. Thanks.

 

[Doug Hillary]

Hi,
I have had extensive experience (many millions of kilometres) with Delvac 1 5w-40 in both diesel and petrol engines

Do not "baby" your vehicle during the run-in phase - avoid high revs when cold and long lugging at any time - short term lugging is ideal. So is constant short term acceleration phases when the engine is warmed up!

Delvac 1 will do very well in your vehicle - the fitting of a by-pass filter will probably prove not to be cost effective however!

Check in the UOA section (petrol/diesel) for details of Del 1's performance in my 500hp DDEC4 Detroit Diesels and in my Porsche V8

Regards
Doug

 

[FowVay]

I too doubt that Delvac-1 is the factory fill in this engine. The factory fill may be a derivative of Delvac-1 but I would bet that the factory fill does differ from the service fill chemistry. However, as Doug mentioned using Delvac-1 would be a great idea for your truck if you plan on logging high mileage while subjecting it to hard use.

I found it interesting that this engine recommended a 5W-40 oil. To me this is the easiest way for the manufacturer to tell you to use a synthetic oil without the legal hassle of putting it in writing. You mentioned using Amsoil and if you're not aware, Amsoil does make a 5W-40 that they claim can be used where a API SL, CI-4 rating is required. It is marketed as their European car formulation and claims some impressive standards.

I would forgo the expense of the by-pass system and spend your money on the higher quality oil such as Delvac-1.

And by the way,, congratulations on your purchase of a VERY nice truck!!

 

[coyotekid]

Thanks for the info, and keep it coming!

So both you guys would skip the bypass system all together? I was planning to use a bypass system along with a high quality synthetic such as Delvac 1 or an Amsoil formulation.

I'm also seriously considering a pre-luber such as the new one Amsoil is selling. What is your opinion of these?

What grade should I run? As I mentioned, the manual states that 15-40 should be used, but 5-40 is preferred in really cold conditions. Is this good advice, or could I run 15-40 year round?

 

[k1xv]

I don't know if you have the older LB7 engine, or the newer LLY. Your window sticker should say. The LLY has EGR and the injectors are placed in the cylinder head so that the valve cover does not have to be removed to change them.

If you have not already, get yourself over to www.dieselplace.com This site has loads of user to user information, with participation by some good GM diesel techs as well.

Now, to answer your question.

It can get pretty cold in Vermont. I am using 5w-40 year round. Right now I am using Shell Synthetic Rotella, which is a Group 3 oil. Mobil Delvac 1 5w-40 is much more expensive, but many here think it is better as it is a "true" synthetic. WalMart now sells Mobil 1 Truck and SUV oil 5w-40 in quart bottles. The formulation is the same as, or very close to, Mobil 1 Delvac.

I changed to synthetic after about 10K miles on conventional 15w-40. Delo 400, Mobil Delvac 1300, and Shell Rotella are all good 15w-40 oils.

I would not use 15-40 oil in any vehicle left out overnight in a Montana winter, even with a block heater. The Duramax in winter can take over 10 miles of driving to warm up.

When you get to the dieselplace site, check out the discussions of secondary fuel filtering. I am using the Nicktane kit, which includes a bracket and all the parts to install a 2 micron Caterpillar fuel filter, designed for a big piece of industrial equipment, in series with your factory fuel filter. This is a preventive measure to keep the fuel to your injectors as clean as possible. There has been some history of injector issues with the Duramax.

It is a great engine. Mine is mated to the Allison automatic, and I love it.

 

[k1xv]

P.S. No, the factory fill is not Delvac 1 synthetic. It is some kind of 15-40

 

[TexasTDI]

A guy at TDIclub.com said he found Delvac-1 at his local Chevy dealer because it's what GM recommends for their Duramax. I've never bothered to ask my local Chevy dealer, though.

If you want to use AMSOIL, their Series 3000 5w-30 is an excellent oil choice.

 

[Pablo]

While I do use the 15W-40 in the winter here with no issues, I'm not really going to recommend it for winters in Montana. It would be an excellent summer oil and I agree with Tex. TDI that the HDD would be my oil of choice for winter/summer.

 

[ebaker]

Seems like Rotella synthetic 5w40 for $12/gal. at WalMart is hard to beat.

 

[coyotekid]

Again, thanks for the info from everyone!

K1XV:

I'm already a member over on thedieselpage.com and I really like the website--it's a wealth of info. Thanks for all the additional info as well. I'm looking into the Racor kit, the Kennedy Mega Filter kit, and the Nicktane setup.

One more question here: Why doesn't Amsoil make a heavy-duty type diesel oil in a 5-40 like most other companies make? Running 5-30 year round would be completely OK, though? I'm a little concerned that 30W oil isn't heavy enough during summer heat.

 

[wulimaster]

quote:

---

Originally posted by coyotekid:
Again, thanks for the info from everyone!

K1XV:

One more question here: Why doesn't Amsoil make a heavy-duty type diesel oil in a 5-40 like most other companies make? Running 5-30 year round would be completely OK, though? I'm a little concerned that 30W oil isn't heavy enough during summer heat.

---

I am running the Series 3000 now in my powerstroke and the ECU seems to be tailered for a 30w. The shifting is quicker without the hesitation between gears and the noise from the injectors is gone. The thermostat controls the engine temperature so I wouldn't worry about summer running.

 

[Hackamore]

I asked a local Chevy dealer what oil they used in the new Duramax and he said Mobil Delvac 1300 15w-40.
Cheers,
Gary

 

[Pick]

Caterpillar 5W40 Syn is Delvac 1 I have been told.

 

[msparks]

Amsoil AMO 10w40 should fit the bill.

Do you have a engine block heater? That would also help in those cold winters.

quote:

---

AMSOIL High Performance Synthetic 10W-40 Motor Oil is Recommended for Applications Requiring the Following Specifications:

• API SJ, SL, CF, CF-2, CH-4, CI-4
• ACEA A3, B3, E3, E5
• DAIMLER CHRYSLER 228.3, 229.1
• CUMMINS CES 20071, 20072, 20076, 20077
• MACK EO-M, EO-M+
• VOLVO VDS, VDS-2
• ALLISON C-3, C-4
• CATERPILLAR ECF-1, TO-2, TO-3
• MAN 271, 3275
• MTU Type 2
• DETROIT DIESEL Series 2000/4000 Category 2
• JASO MA (Motorcycle)

AMSOIL High Performance Synthetic 10W-40 Motor Oil remains fluid at temperatures as low as -54°F (-48°C), permitting easy engine cranking for quick starts. During sub-zero temperatures, it flows to all parts of the engine much quicker than conventional petroleum oils, greatly reducing the rate of wear and increasing engine life

CCS Viscosity @ -20°C, cP (ASTM D 2602) 4240

In light-duty and non-turbocharged diesel engines, change oil at two or more times the engine manufacturer's recommended drain intervals if the findings of used oil analysis support those drain intervals or six months, whichever comes first.

---

This would be my vote, you should be able to get it for less than Delvac at less than $20/gallon shipped. Most places have delvac 1 for around $25-28 plus tax

 

[msparks]

BTW if cost is not an issue, and your running a by-pass filter with oil anlysis. The Series 3000 5w30 HDD is my first recommendation.

In the above post I was just giving another option.

 

[Jelly]

Given the climate in which you live, I'd use Rotella-T 5w-40 in combination with a AcDelco filter, both available from local stores...

 

[Lightman]

I run an amsoil dual bypass system and delvac 1 in my 04 cummins. My oil analysis reports so far have been fantastic. I definitely recommend this system, and using my 10k filter and 20k bypass filter and 40k oil change interval, it's cheaper than 5000 mile changes with rotella or the like, including filters. I don't do it because it's cost effecive(although it is), I do it because I like spending more time driving my truck than underneath it changing oil. I also like the increased protection. Who cares about cost effective when you're talking about a private owner using premium synthetics on a $40k truck?

I would not use a 30 weight in a heavy duty diesel truck. Maybe the tdi'ers can argue it's fine in a puny 1.9l, however I'm personally not comfy with it. Show me UOA's all day, it won't go in my truck. When towing 10k lbs up a hill, that stuff gets hot. I like the extra thickness of a 40wt.

My guess is the dealer was partially wrong, and the duramaxes are filled with delvac 1300 from the factory. No evidence to support this, just a likely mistake from the dealer, and I also doubt they are dumping d1 in at the factory.

 

[Ken2]

coyotekid,
How long do you plan on keeping this truck? 500,000 or more miles? If so, a bypass filter will pay for itself. 100,000 or 200,000 miles? What's the point? The engine will still be in good condition.

If you extend oil drains longer than the requirement in the owner's manual, you do need oil analysis at each oil drain interval to maintain your warranty.

5W-30 diesel engine oil is the future. It will save 1 or 2% of fuel, but is not yet recommended by the engine makers. Again, if you use it, you'll need oil analysis to protect your warranty.

Schaeffer's #700 premium synthetic blend oil is labeled as a 15W-40, but it actually tests as an 8W-40 (if there was such a thing). It would work very well in your engine year 'round, combined with heat on the engine in minus weather. It is the equal of Mobil Delvac 1 and other top quality oils at a lower cost.


Ken

 

[Rat407]

I know of a DMax owner that tried the Series 3k 5w-30 and he had excessive engine noise. Didn't like that and switched back to the AMSOIL 15w-40 and the noise went away. Doesn't it state in the owners manual that a 5w-30 isn't recommended? His DMax is an 03. Just thought I would imput this info incase someone else has experienced the same with 5w-30 in a DMax