Question about my new LBZ engine.

modiesel · 02-08-2007, 10:48 PM

Hi folks,

I am new to this forum so excuse me if this topic has been overdone. I bought a 2007 Silverado 2500HD in January with the Duramax LBZ and the 6 speed Allison. I know the truck was built in early 2007 and I think it was designed to run "low diesel" instead of "ultra low sulfer diesel". The air cleaner has a sticker on it that says 2006 model year and the fuel gage does NOT have the "Ultra-low sulfer diesel only" label on it. I'm thinking this was a late 2006 engine put in the early 2007 truck. Does this mean I can run both low and ultra low? Should I only run "low sulfer" ? Is there any advantage to running low versus ultra low? The dealership service department say "All 2007's run ultra-low". I think mine might be an exception. If anyone can shed some light on this I would appreciate it.

Thanks

**ob_1jr** · 02-09-2007, 01:07 PM

You can run both, but I would run the low sulfur stuff until you can't get it anymore. If you run the ULSD, I would run an addivite in the tank with it just for piece of mind.

Diesel Warrior · 02-09-2007, 06:32 PM

I talked to my local Detroit Diesel/Allison dealer (Penn Diesel). According to them, the oil companies are putting in additives to raise the lubricity of ULSD, but he said that since there arent any ULSD million mile engines yet to examine they are recommending additives for lubricity. They also told me cetane booter was a waste of my time. I am running an additive to make me feel better and for gelling (my buddy just got towed due to gelling at -5*F). There are LOTS of opinions on this. Good Luck!

eyrichclark · 02-09-2007, 08:11 PM

i have a 2007 that the sticker on the engine say its a 2006. i asked my service tech and he told me to run low sulfer, that the ultra low sulfer would not run as good.

**Diesel Nut** · 02-09-2007, 08:49 PM

You can run either. 2007 trucks designed to meet 2007 emissions are required to run ULSD to meet the 2007 emissions. I agree on the fuel additive. I used to work in refineries and I don't trust my truck's motor to whatever jackass they are paying $12 a hour to blend the proper amount of additive.

I use this every tank.

**Tow Master** · 02-10-2007, 12:16 AM

I personally have no clue what the difference is between the two. I just checked stanadynes website and WOW they have alot of information and tell you exactly what additive you need. They have 3 pages of information and explain what the differences between the two. Ill be studying this real soon.

http://www.stanadyne.com/new/index.asp

Under additives then diesel fuel update
Ultra Low Sulfur Diesel
Beginning in 2006 diesel fuel for on-highway
use must have no more than 15 parts per
million sulfur. This is a
97% reduction from the
previous limit of 500 ppm. Sulfur is removed
from diesel fuel at the refinery by a
process
called hydro-treating which also affects the
fuel in other ways. The American Society for
Testing and Materials (
ASTM) publishes the
standard for mineral diesel fuel‚Äî
ASTM D975
which the refineries comply with.
Advantages of ULSD
+
Reduced exhaust emissions
+
Improved cold startability and reduced white
smoke at cold startup
Disadvantages of ULSD-
Higher Cost
-
Lower energy content. Less BTU‚Äôs per
gallon means reduced power and fuel
economy
-
Possible premature fuel system wear. The
process of removing sulfur can also reduce the
natural lubricity of the fuel. There is now a
lubricity specification in the D975 standard but
it is not as high as what the fuel system
manufacturers recommend.
-
Compromised fuel stability. ULSD tends to
be less stable and will deteriorate sooner than
the previous diesel spec.
-
Fuel System leaks. Reducing sulfur also
reduces aromatics. This can result in rubber
seals an hoses in some fuel system
components shrinking and resulting in fuel
leaks. NOTE: Stanadyne fuel systems do not
use natural rubber seals but use Viton¬Æ
seals
instead

DeereMan · 02-11-2007, 04:32 PM

Modiesel,
Becasue your truck is equipped with the LBZ engine, I suspect you actually have a 2007 "Silverado Classic" 2500HD Duramax. These trucks were all built in the 2006 calendar year and sold as 07 models. The LBZ engine is designed to run either LSD or ULSD. The NEW style 2007 Silverado 2500HD, ones actually built after Jan 01 07, will be equipped with the LMM engine and have yet to be delivered to customers. When you go looking for parts for your truck you will learn quickly to specify you have an 07 "Silverado Classic" 2500HD.

modiesel · 02-14-2007, 11:33 AM

Thanks for the input. I will run low sulfer and I bought some Amsoil ADF additive to use in the event that all I can find is Ultra low sulfer.

delawitt · 02-14-2007, 01:46 PM

If the sticker in the engine compartment says 2006 emissions then thats what emmisions laws it was built under.

ffemtp · 05-15-2007, 06:19 PM

Out of curiosity, the owners manual specifically states (paraphrasing here) "Do not add any additives to your diesel fuel unless they are GM approved". I have always ran Diesel Kleen in my trucks. Why is GM stating this and should I still be adding the additive? I personally think the additive should be added because of the additional lubricity, just not going against the manual.