Switch To Synthetic Oil - When?

[MR SHORTY]

So how many miles before she's really "broken in" so I can switch to synthetic motor oil?

Hopefully for an MPG gain.

Guess I can't run Amsoil in my LMM, since their 15-40 is not CJ-4 compliant.

[ohmatman]

Amsoil makes an oil that is CJ4 compatible, im going to put it in my LMM, i am going to wait till my driver info center tells me to change it. I believe the Amsoil is called DEO series ,if you call them they will tell you what you need.

[MR SHORTY]

Originally Posted by ohmatman

Amsoil makes an oil that is CJ4 compatible, im going to put it in my LMM, i am going to wait till my driver info center tells me to change it. I believe the Amsoil is called DEO series ,if you call them they will tell you what you need.

Just not the GM recommended weight 15-40 for the LMM.....

[Diesel Nut]

The Amsoil 5W40 (DEO) CJ4 rated oil is just fine for your LMM. It is still a Compression Rated 40 weight oil. With multi weight oils, the first number is the Winter (hence the W) weight. This is the cold starting viscosity. At operating temp, it is still a 40 weight oil. It is just a little easier flowing when its cold.

Here is more info.

[MR SHORTY]

Thanks.

Just came from service at the local "GM Quick Lube" which by the way is FANTASTIC. In and out 15 mins no appointment needed. 4 bays no waiting - separate of regular service repair. I guess they are Ol' Skool because they stickered my window next service 3 months / 3,000 miles.

But guess what they are told to set the tire pressure to? 50/50psi front and rear - which makes the dash flash like a neon sign. Same place that gave me the run around on resetting the DIC last service 3 months ago. So I asked again and now they say not that big a deal to reset it - guess they are learning the new trucks finally - after all the '08's are out now.

I have them looking into the ebony cloth seat LINT bulletin - we'll see if they will do that under warranty. They always ask where I bought it - because a warranty repair like that they want you to go to the selling dealer if it's within 50 miles - WTF. I bought at DAVE SMITH 360 miles away - which by the way is also FANTASTIC place to buy. (ie $500 UNDER invoice).

usautosales.com - Dave Smith Motors - Hassle Free Buying - Autos Trucks Vans Accessories

[Diesel Nut]

I bought my Dodge from Dave Smith! Great place!

[pete37922]

i started using syn oil about 30,000, but thats when Powerstoke says thier piston rings are set in the cylinders...!!!

[07-LMM-Turbo]

not sure of switching to AMSoil yet, not an expert in diesel oils......

***********AMSOIL Synthetic 5W-40***********

- AMSOIL - AMSOIL Synthetic 5W-40 Premium Diesel Oil (DEO)
- API CJ-4, CI-4+, CH-4, CF, SM, SL, SJ...
- Aftermarket oil additives are not recommended for use with AMSOIL motor oils.

Kinematic Viscosity @ 100°C, cSt: 15.3
Kinematic Viscosity @ 40°C, cSt: 92.6
Viscosity Index: 176
CCS Viscosity @ -30°C, cP: 5852
Flash Point °C (°F): 226 (439)
Fire Point °C (°F): 242 (468)
Pour Point °C (°F): -44 (-47)
Noack Volatility 250°C for 1 hour, % weight loss: 8.9
Four-Ball Wear Test (40kgf, 75°C, 1200 rpm, 1 hr) Scar diameter, mm: 0.44
Total Base Number: 8.00
High Temperature/High Shear Viscosity, cP: 4.2
Sulfated Ash Content, wt. %: 0.97

***********mobil delvac 1300 super 15w-40***********

- Mobil Delvac 1300 Super
- API CJ-4, CI-4 PLUS, CI-4, CH-4, CF/SM, SL
- exceed the API CJ-4, CI-4 PLUS and CH-4 service categories as well as key Original Equipment Manufacture (OEM) requirements for 2007 engines.
Mobil Delvac 1300 Super

cSt @ 100ºC: 15.0
cSt @ 40ºC: 114
CCS: 6500 @ -20ºC
MRV: 19,000 @ -25ºC
HTHS @ 150ºC: 4.3
Viscosity Index: 137
Sulfated Ash, wt%: 1.0
Total Base #, mg KOH/g: 10.5
Pour Point, ºC: -30
Flash Point, ºC: 236
Density @ 15ºC kg/l: 0.876

[MR SHORTY]

AMSOIL Turns me off with their MLM marketing just like AMWAY...... But I noticed yesterday while walking the dog that the NAPA store in town sells AMSOIL........

Mobile Delvac Super 15W-40 is NOT synthetic....... It's dino....

Mobile Delvac 1 5W-40 is the synthetic.......

Mobil Delvac 1 5W-40

The Stealership is using Mobile Delvac Super to GMPP service my rig free for a year. I am going to switch to synthetic right after that at approx 10,000 miles - and most likely go Mobil Delvac 1.

If you compare the rating of Mobil dino to Mobil synthetic - they are darn near identical. In fact the dino has less ash. Makes me think continuing to run the non-syn will be just fine. Plus 15W-40 is the recommended oil from GM, and the synthetic only comes in 5W-40 which really is for temps below zero and up. It never gets even near below zero where I operate the beast.

The main reason i would run synthetic besides possibly better protection - would be if it increases MPG.

[07-LMM-Turbo]

Originally Posted by MR SHORTY

Mobile Delvac Super 15W-40 is NOT synthetic....... It's dino....

Mobile Delvac 1 5W-40 is the synthetic.......

Mobil Delvac 1 5W-40

Makes me think continuing to run the non-syn will be just fine. Plus 15W-40 is the recommended oil from GM...The main reason i would run synthetic besides possibly better protection - would be if it increases MPG.

most importantly, Mobil 1 5w-40 isn't certified as CJ-4 compatible

"Mobil Delvac 1 5w-40: API CI-4 PLUS/CI-4/CH-4/CG-4/CF-4/CF/SL/SJ"

our manual says:

-- CJ-4 required
-- 15w-40 preferred above 0 degrees F (-18 degrees C)
-- no additives

...using ther oils could cause problems with your engine down the line...