Duramax And ULSD - Montana Owners Club

Cat320 · 12-01-2006, 01:46 PM

There has been so much discussion concerning the new ULSD, I thought I'd check with the local dealers. Called one GMC and three Chevy service managers. All four were adamant that the 07 Classics and earlier DMaxs need no additives to run on either the old or new diesel fuel. One pointed out that GM approves some additives (Stanadyne as well as their own brand), but they are not needed. Just reread my owner's manual and, interestingly, it says my truck SHOULD us ULSD..."It is important that diesel-powered trucks are refueled only with ultra low sulfur fuel. The emission control system requires the use of diesel fuel with ultra low sulfur (0.0015% by weight, or 15 ppm, maximum) content."

Go figure.

Montana Sky · 12-01-2006, 02:10 PM

Bert,
Pretty much got the same answer from GM when I called up the offices to get their answer/opinion. After running 1,000 miles of ULSD this summer, lost an average of 3 mpg, louder "knocking" noise, as well as what felt like a reduction in power, I still question what the long term effects are going to be?? Makes me think the longevity of the diesel motor will be compromised from here forward? Think I will stick with adding a bottle of GM Fuel conditioner to each tank. Better safe than sorry.

Thank you for taking the time to contact your local dealers and posting your findings. This is a topic that has many of us very interested and concerned.

snfexpress · 12-01-2006, 02:33 PM

Bert,

Your owner's manual states you must use ULSD because your truck is a 2007. For those of us with earlier year models, it has been somewhat of a quandry.

I, too, spoke with a few diesel techs at two different dealerships. The universal response was that they didn't know how the new ULSD would affect 2006 and earlier models. Stanadyne is a GM-approved additive, and all suggested that until things shake out that I should run Stanadyne whenever I add a tank of ULSD. The questions that were brought to the forefront were are the refineries adding the additives? Or are the jobbers? Or..?

Interestingly, I have also spoken to a fair amount of fuel station owners. Not one could tell me if the ULSD had additives as mandated. In response to my question of why and who, their responses were that they knew additives were supposed to be put in, but they assumed that they were in the fuel prior to being delivered to their station. Each and every one of the owners told me adamently that they would find out where in the delivery process the additives were being added.

I am glad that you got the information that assuages your fears. For me, I will continue to add a bottle of Stanadyne each and every time I put a tank of ULSD in my 2006 until I am told definitively that it is not necessary and that if injector problems, etc. occur, that GM will take care of the problem, regardless of the warranty. I figure $6 per tank is cheap insurance.

Also, I would like you to post when your truck tells you that the filter system needs to be purged by running at a high idle. Please let me know if you are able to continue to drive (and tow) or whether you must stop at the side of the road (as was told to me by two general managers of GMC dealerships).

Just my 2 cents...

ols1932 · 12-02-2006, 03:06 AM

snfexpress,
I would continue to use whatever additive you are using until this all shakes out. When even the dealers don't know, how are we supposed to know? You and I and everyone else on the forum know that the refiners and jobbers aren't going to spend the money to add any additives.

Orv

snfexpress · 12-02-2006, 05:49 AM

Orv,

That's the interesting thing. From what I have been told, it is mandated that additives are put in the diesel fuel at *some* point in the distribution chain. In fact, it's the number one response to why diesel is more expensive than unleaded - additives are being put in. But, I haven't found one person in the chain who can tell me that a) additives are in the fuel and b) when they were put in.

Yes, I will continue to add $6 to a tank of ULSD until it all shakes out.

Glenn and Lorraine · 12-02-2006, 06:43 AM

I am now on my 3rd tank of ULSD and see absolutely no difference in performance. Have not checked fuel mileage as I see no reason to check it. Even if I was getting lesser MPG there would not be a whole hell of a lot I could do about and adding an additive just unnecessarily adds to the cost which is already too high.
Personally I feel this whole USLD issue is way over rated. I think it was Shakespeare that said "Much ado about nothing"?

Cat320 · 12-02-2006, 07:28 AM

snfexpress...my truck is an 07 Classic, which means it is exactly like yours (looks/engine/drive train/interior/etc.) except the title says 07 rather than 06.

snfexpress · 12-02-2006, 08:29 AM

Bert,

Good to know that. In my manual, it doesn't reference ULSD. Who knows...

gkbutler · 12-02-2006, 08:52 AM

I've been using ULSD since October and I haven't had any problems. Mileage really doesn't matter, when the tank to a quarter tank; I fill it up. The only thing I have seen is that the exhaust is cleaner when I accelerate. Used ULSD when we towed to FL and didn't see any difference at all while towing. I would assume that if I have problems with my engine prior to the 100K, GM will stand behind the warranty.

DonandBonnie · 12-02-2006, 11:49 AM

Bert and Betty,
Our 2007 Classic Silverado 3500 should be on a train somewhere headed to our dealer as we speak. I asked the dealer the same question about the ULSD and got the same reply, that the 07 Classics work equally well on either grade fuel. I wonder if the comment in the owner's manual is designed to fend off the lawyers and make the EPA happy. I believe the word "SHOULD" encourages the use of USLD, but does not make its use mandatory. I would think that if you absolutely positively had to use ULSD, you would see some stronger language that would inform you that your truck, and possibly the world, would come to an immediate and disasterous end if anything other than ULSD were to pass thru the fuel tank. I think there is a similar type warning in the owner's manual of gasoline vehicles warning about using other than unleaded gas.
Don

Montana Sky · 12-02-2006, 06:19 PM

I guess it all depends on how long you keep the truck, and how many miles you want to put on your truck. A lack of proper "lubricity" is one of the main problems/concerns with the new fuel. Internal wear and breakdown will follow with continued use of ULSD if the correct amount of additives are not added during the distribution process. I guess if the trucking industry is concerned about the long term effect of ULSD, I should be as well.

Glenn and Lorraine · 12-03-2006, 12:56 AM

Quote:

quote:Originally posted by Montana Sky

I guess it all depends on how long you keep the truck, and how many miles you want to put on your truck. A lack of proper lubrication of the motor is one of the main problems/concerns with the new fuel. Internal wear and breakdown will follow with continued use of ULSD if the correct amount of additives are not added during the distribution process. I guess if the trucking industry is concerned about the long term effect of ULSD, I should be as well.

But Dave, Just WHERE does this info come from?? Is it a very reliable source such as the Duramax or any diesel engine manufacturing engineers?? Or is it coming from some Internet EXPERT on everything wanna be engineer??
Again, I feel they are reading a whole lot more into this ULSD issue than really exists and I refuse to get all bent out of shape about it.

Steve and Brenda · 12-03-2006, 02:00 AM

Do not confuse yourself with lubrication and lubricity folks. Lubrication of major machine parts obviously is from the motor oil and Diesel fuel lubricity concerns the fuel injection components. The LSD Diesel which has 500 parts per million of sulphur used that sulphur to lubricate the fuel injection pump components. The new ULSD has only 15 PPM sulphur meets a certain standard where an additive is used in place of the sulphur to lubricate those components.

If your chevy Duramax sales code is LMM you have a 2007.5 Diesel that REQUIRES ULSD designed to use that fuel and may be damaged using the LSD. If you own the sales codes of LBZ, LLY or LB7 your Duramax was made before the ULSD requirement and may run on either blend of Diesel.

http://www.dieselplace.com/forum/index.php

http://www.fullsizechevy.com/forums/

http://www.gm-trucks.com/forums/

DonandBonnie · 12-03-2006, 04:02 AM

I just checked my purchase agreement. It says that my Duramax engine will be an LBZ. Sounds like I should be ok with either kind of fuel.

Cat320 · 12-03-2006, 07:55 AM

Steve...according to all the local GM/Chevy dealers, there are no LMMs on the road. They will be in the new body style 07 heavy duty models (2500/3500) which will not hit the street until spring at the earliest. ALL 07 Silverado Classic D/As have the LBZ engine.

Montana Sky · 12-03-2006, 09:36 AM

Glenn,
My info comes from bulletins that GM sends out, my local GM service departments, a friend who's job deals with GM, folks who are fleet managers for 2 large trucking companies that roll more than 15,000,000 miles a year on their fleet, a fuel depot supervisor, a city bus driver, and first hand experience directly from my truck. Yes, I read a great deal of information on the internet, that does not make me an expert, nor do I consider it "100% fact". I want to see the odometer roll 300,000 miles. At the rate of miles I put on my truck, it will be less than 8 years old. It seems that you have no concern over the new fuel, I hope for your "and my" sake that proves to be true.

Bob Pasternak · 12-03-2006, 10:12 AM

The only way a Chevy/GM odometer will roll 300,000 is if it is being towed by a Dodge/Cummins!!!

Mac · 12-03-2006, 10:43 AM

Quote:

quote:Originally posted by Bob Pasternak

The only way a Chevy/GM odometer will roll 300,000 is if it is being towed by a Dodge/Cummins!!!

Then obviously your Dodge is much different than the one and ONLY I ever owned.

mac

DonandBonnie · 12-03-2006, 11:00 AM

Hey Bob,
My son pretty much agrees with you. I doubt if I'll ever find out however, because he can't keep his Dodge/Cummins out of the repair shop long enough to tow my soon to be delivered Silverado anywhere.

Don

BigAl52 · 12-03-2006, 11:06 AM

I kinda have the same attitude that Glenn does lets just wait and see. I been pushin a Cummins down the road for 33 years. No that doesn't make me an expert but the company I work for has a couple of mechanics that I would put up against anyone in the country. I have learned alot from them and from a freind who is one of GM's top rated mechanic's and does alot of diesel work. He says the new Duramax's will be better than alot of people are thinking they will be. In closing I will say that I have not seen any change in the N14 525 that I use everyday to pull 85000lbs of feed back and forth from Denver and Ft. Morgan to Platteville Colorado. I also have not seen any change in my Dodge. I can still remember all the stories of how the low sulfur diesel fuel was going to ruin the diesel engines of yesterday. That wasn't that long ago that that change took place either. Al

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