Duramax LMM & GM's Bio-Diesel recommendations

[More Power]

GM’s 2007 Duramax owner’s manual supplement states that it is acceptable to use diesel fuel containing up to 5% bio-diesel (B-5).

Jim

[DieselMonk]

The Duramax Diesel manual for my 07 Classic (LBZ) says that too. It also says only to fuel up with ULSD! While on the engine everything is saying the emmisions standard is for 06. Seems to be the later 07 Classics have the same manual than the LMM!

[Dakster]

The Duramax Diesel manual for my 07 Classic (LBZ) says that too. It also says only to fuel up with ULSD! While on the engine everything is saying the emmisions standard is for 06. Seems to be the later 07 Classics have the same manual than the LMM!

Does your dashboard where the fuel gauge is read "Ultra Low Sulfur Diesel Fuel Only". All of the LMM's I've looked at / test driven have that printed on the dashboard....

[More Power]

Here's the Instrument panel found on a 2007 LMM 3500HD.



Yes, the fuel gauge says "Ultra Low Sulfur Diesel Fuel Only".

Also, note the lack of a redline on the tach....

Jim

[Dakster]

Here's the Instrument panel found on a 2007 LMM 3500HD.



Yes, the fuel gauge says "Ultra Low Sulfur Diesel Fuel Only".

Also, not the lack of a redline on the tach....

Jim

I guess that means its ok to run the RPM up to 5k... (just kidding)

Note the speedometer goes to 120... Like a stock truck will go 120mph, I'm sure its like my Denali and Suburban where right around 100mph is the fuel shut-off...

[DieselMonk]

Does your dashboard where the fuel gauge is read "Ultra Low Sulfur Diesel Fuel Only". All of the LMM's I've looked at / test driven have that printed on the dashboard....

I have the canadian version instrument cluster and it doesnt say anything on the fuel gauge. The only thing that surprised me was that my manual for the Duramax is the same that the LMM's got.

[DieselMonk]

I guess that means its ok to run the RPM up to 5k... (just kidding)

Note the speedometer goes to 120... Like a stock truck will go 120mph, I'm sure its like my Denali and Suburban where right around 100mph is the fuel shut-off...

Raise the speed limiter and some folks will look a bit funny when the theng keeps on climbing!

[Duramaster]

That's all right. I just replaced the fuel filter on a 2006 GMC C-5500 with an LLY. It only has 2300 miles on it and the filter is already plugged!!! WHy you ask? Because the City of Portland is using B-20 in all their diesel vehicles. This is not the first vehicle of theirs that has been towed in because of the STUPID B-20 fuel!!!

[gillguy]

I just replaced the fuel filter on a 2006 GMC C-5500 with an LLY. It only has 2300 miles on it and the filter is already plugged!!! WHy you ask? Because the City of Portland is using B-20 in all their diesel vehicles. This is not the first vehicle of theirs that has been towed in because of the STUPID B-20 fuel!!!

I see quite a few saying they run B20 with no problems.
Been thinking about trying it myself since it's cheaper

[ISEEDIT]

Because the City of Portland is using B-20 in all their diesel vehicles. This is not the first vehicle of theirs that has been towed in because of the STUPID B-20 fuel!!!

Supposed that the Bio is cleaning all the sludge out of their tanks? I'd be willing to bet they don't have filters on their bulk tanks/pumps . . . Bulk tank filter maintinance is key, unless a guy likes having their diesel filters plugged. I don't believe you mean it's the B-20 causeing the problem, but some that lerk and contribute here may think Bio is bad.

[seth_95]

This is why biodiesel is getting a bad name. Biodiesel acts as a solvent and when biodiesel is first added to a fuel station tank it is reccomended that they fill it with B100 to act as a super-solvent to flush the system then fill it with B20 or whatever the desired Biodiesel mix is. Most of these stations dont service their fuel filters as they should when they start selling biodiesel. I have filled up from a Petro Station right after a fuel filter replacement and only went 80 miles and the fuel filter was plugged and I wasnt running biodiesel. It all depends where you get your fuel. I have ran a B20-B50 mix in my 04 Duramax for the last 40,000 miles and havent had one hickup! I seervice my fuel filter every other oil change and the filter isnt any-dirtier than it was before. I get my bio-diesel from Gen-X energy in washington which services portland with their bio-fuel. There methanol detection currently isnt picking any-traces of methonal left in thier fuel. They also meet ASTM standards. If you run ASTM fuel, and used stored fuel within 7 months, you wont have any problems!