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Secguru · 06-24-2011, 09:42 AM

Call me a skeptic. The truck manufacturer is motivated to get you to buy a new truck every few years. Changing the oil at 5,000 miles costs very little compared to changing out the engine before its natural life is over.

Anything they can do to accelerate the demise of the engine is good for the manufacturer. Getting you to take the oil out to its total end of serviceable life advances their agenda.

I routinely get 350,000 miles out of my gas engine automobiles with 3,000 mile oil changes, never having to replace engines that have an estimated 100,000 mile serviceable life. I have a queue of people wanting my old cars, which are still in like-new condition after ten or fifteen years.

Why wouldn't I apply the same logic to a $55,000 truck with an $8,500 diesel engine? I want this truck to last me 20 to 25 years. (Detroit isn't building 5.9 Liter engines anymore). I want to protect my investment. Oil changes are a minimal investment. I also use Synthetic oil and extra filtering. - Call me crazy, but I'm betting that my total cost per mile beats most people's by a long shot.

Good trucks are expensive now. It pays to take care of it instead of trading up every 2 to 5 years.

JBinKC · 06-24-2011, 02:58 PM

I towed 5,700 miles this spring with my '09 Silverado Duramax and '07 Classic 31. The route was through the great Southwest and included 2,000 miles on the WBCCI Southwest Adventure Caravan -- my best vacation ever of all time. I averaged 13.2 MPG for the two-month roundtrip. I used the Tow/Haul Mode for the purple mountain majesty part of the trip. I took it out of Tow/Haul Mode for the fruited plain part. The Duramax loafed up to 11,400 feet at less than 2,000 RPM and less than 190 degrees transmission temperature with the 9,000-lb Airstream in tow. Coming down from the Continental Divide to soggy K.C., the Allison transmission kept the speed down so constant braking wasn't necessary. The picture is of our caravan parked at Valley of Fires Recreation Area, NM, just one of a hundred excellent events along the Southwest Adventure Caravan route. What a wonderful trip! What a wonderful truck!

Bill M. · 06-27-2011, 06:22 AM

Hi John. It was a good caravan. and a good test for a TV

ZoominC6 · 06-27-2011, 06:31 AM

Quote:

Originally Posted by TinCanLand

Anyone using the 4.11 rear axle?

A Duramax with a 4:11 rear end would no doubt tow the Queen Mary! These rigs are awesome enough without adding a 4:11 in our opinion; however, that would be something to behold!

JFScheck · 07-03-2011, 03:06 PM

So, as you see from the blurry iPhone picture - I only have 3,800 miles on my rig so she is yet fully broken in - but to my amazement - pen & paper calculations have me at 20.1 mpg out on the highways averaging between 60 - 65 mph with me, an ARE topper & 500 lbs. in the bed - so I switched the display to "Fuel Economy" and the engine management had the same story to tell...

So, my story fellow Truckers - with the massive frontal area of our Trucks, reduce your speed down 10 mph and you might pick up an extra mile or two per gallon!!!

Still, great time for us all as Diesel Truck owners, who would have imagined 400 horses & 800 lbs. torque at 20 miles per gallons at 65 mph (and yes I have a heavy right foot)...

July 7th I upgrade from my OEM short bed 26 gallon tank to a Titan 50 gallon (plug & play) tank - after a quick reflash of the ECM and that "Miles to Empty" should look a bit more presentable...

**moosetags** · 07-03-2011, 04:25 PM

Thanx for the info, John. After the Titan retrofit, you will be hovering at near 1,000 mile range. Please keep us posted on the tank install and results. mAre you doing the tank installation yourself or having it done?

Brian

JFScheck · 07-04-2011, 12:17 AM

Brian, as easy as it appears via the tube videos as posted, I'm still having the pros perform the install.

What's the expected delivery date of your DuraBeast?

tinearpaul · 07-04-2011, 02:23 PM

Just went out and looked at our 2011 3500 Denali SRW standard bed crew-cab for tire type. They are Michelin 265/70-18 LTX AT-2 LRE 124/121R Made in Canada. It appears the 2500HD's (both Chevrolet and GMC seen at the dealers) get Good Year or Bridgestone somethings. The 2500HD Denali's get the five spoke polished Aluminum wheel (shown on brochure and web site) but the 3500 Denali's get a different polished Aluminum wheel that looks different than the standard wheel on the 2500's. I was expecting the five spoke wheel and probably Bridgestone or Good Year but when we picked up the truck at Sierra Motors in Jamestown, CA but it had these different wheels and Michelin tires. I was happy! I saw a Chevrolet 3500 dually at the local dealer when I was getting my oil changed Tuesday and it also had six Michelin LTX AT-2 tires, don't remember looking at the size. So I guess the 3500's are getting Michelin and the 2500's get Good Year or Bridgestone. Ours is coded for GVW rating of 11,500 lbs. and that may also key in a different wheel and tire for the 3500 model.

Paul

**moosetags** · 07-04-2011, 03:11 PM

Thanks for the tire info, Paul. I just looked at those Michelins on line. I sure hope that Fred shows up with a set of those.

Brian

**moosetags** · 07-04-2011, 03:23 PM

Quote:

Originally Posted by JFScheck

Brian, as easy as it appears via the tube videos as posted, I'm still having the pros perform the install.

What's the expected delivery date of your DuraBeast?

Hey John, what kind of pro are you getting to do thew install, and what kind quote did you get to have the work done?

Fred (the Durabeast) is scheduled to be built in Flint during the week of July 11th.

Brian

flyingfinn · 07-04-2011, 09:23 PM

Thanks to everyone who picked up on the topic of mpg for a Duramax. My 2008 is totally stock. It is a 4x4, standard bed. I keep reading about the chips that improve mileage and power. Also, is there any benefit in getting a "better" air cleaner that breathes better and that could be re-used by washing? Would synthetic oil improve the mileage and go longer between changes?

r carl · 07-05-2011, 06:34 AM

Quote:

Originally Posted by flyingfinn

Thanks to everyone who picked up on the topic of mpg for a Duramax. My 2008 is totally stock. It is a 4x4, standard bed. I keep reading about the chips that improve mileage and power. Also, is there any benefit in getting a "better" air cleaner that breathes better and that could be re-used by washing? Would synthetic oil improve the mileage and go longer between changes?

I would recomend KILLING the DPF and getting a real HP TQ jump.
K&N type air filters pass more silica because of their bigger pores,
keep the stock air cleaner, its best for your use.
If you want to go to a high quality oil get dino LE or synthetic Amsoil as they are the best, period!
You can safely extend your drain intervals 3 times with those 2 oils.

redeagle313 · 07-05-2011, 07:58 AM

Quote:

Originally Posted by tinearpaul

Just went out and looked at our 2011 3500 Denali SRW standard bed crew-cab for tire type. They are Michelin 265/70-18 LTX AT-2 LRE 124/121R Made in Canada. It appears the 2500HD's (both Chevrolet and GMC seen at the dealers) get Good Year or Bridgestone somethings. The 2500HD Denali's get the five spoke polished Aluminum wheel (shown on brochure and web site) but the 3500 Denali's get a different polished Aluminum wheel that looks different than the standard wheel on the 2500's. I was expecting the five spoke wheel and probably Bridgestone or Good Year but when we picked up the truck at Sierra Motors in Jamestown, CA but it had these different wheels and Michelin tires. I was happy! I saw a Chevrolet 3500 dually at the local dealer when I was getting my oil changed Tuesday and it also had six Michelin LTX AT-2 tires, don't remember looking at the size. So I guess the 3500's are getting Michelin and the 2500's get Good Year or Bridgestone. Ours is coded for GVW rating of 11,500 lbs. and that may also key in a different wheel and tire for the 3500 model.

Paul

On the HD's we build at Fort Wayne, the 17 inch standard tires are Bridgestones, the 18 inch optional tires are the Michelins, and the 20 inch optional tires are the Goodyears.

**moosetags** · 07-05-2011, 08:32 AM

My understanding is that the regular cabs and crew cabs are built in Flint, and the extended cabs are built in Fort Wayne. Is this correct?

Brian

D Air Cloud · 07-06-2011, 01:42 PM

Quote:

Originally Posted by flyingfinn

Thanks to everyone who picked up on the topic of mpg for a Duramax. My 2008 is totally stock. It is a 4x4, standard bed. I keep reading about the chips that improve mileage and power. Also, is there any benefit in getting a "better" air cleaner that breathes better and that could be re-used by washing? Would synthetic oil improve the mileage and go longer between changes?

There are many companies that market chips or programmers for the 2010 and earlier Duramax. GM believes these programmers increase horsepower and torque beyond the design limits of the engine. When a customer brings their Duramax in for warranty service on the engine/transmission, the engine control module (ECM) is checked for the presence or history of a chip or programmer. If the ECM’s programming has been altered, the remaining powertrain warranty will be canceled. On the 2011 Duramax, GM has blocked access to the ECM through the OBDII port. As a result, only a few companies have developed programs for these new engines.

The stock AC Delco is actually a very good air filter. Google “spicer air filter study”. This study compares the performance of many popular air filters. Donaldson also makes good air filters.

I have used synthetic oil in all my vehicles for the last fifteen years. I have a 2008 Duramax LMM like yours. At the first oil change I put synthetic oil in it. Checking the oil one day, the dip stick indicated too much oil in the engine. That didn’t make sense. Did some research and learned that GM, Ford and Dodge are all plagued with this problem. When these motors go into the regeneration cycle to clean the DPF filter, a small amount of fuel is getting into the crankcase, which over time, is causing the oil level to rise. To solve the potential oil dilution problem, I now change my oil every 5,000 miles. For me, throwing synthetic oil out after only 5,000 miles was a waste. So I now use a dino oil, Shell Rotella T in my Duramax.

The 2011 Duramax LML, solves the oil dilution problem by not using the engine's injectors to spray fuel into the exhaust. Instead, a ninth fuel injector was added to the exhaust system to be used during regeneration.

Silver Otter · 07-06-2011, 02:19 PM

Quote:

Originally Posted by r carl

I would recomend KILLING the DPF and getting a real HP TQ jump.
K&N type air filters pass more silica because of their bigger pores,
keep the stock air cleaner, its best for your use.
If you want to go to a high quality oil get dino LE or synthetic Amsoil as they are the best, period!
You can safely extend your drain intervals 3 times with those 2 oils.

How does one kill the DPF?

r carl · 07-06-2011, 02:39 PM

Quote:

Originally Posted by gheuer

How does one kill the DPF?

By removing the system. There are diesel guys in the diesel forums that know way more than me, they eat, sleep, and live diesels. You can go to one of the popular diesel forums and learn there what needs to be done. Personally if I had a 2008 I would remove the DPF and put on a free flowing cat back exhaust.

Silver Otter · 07-06-2011, 08:24 PM

Quote:

Originally Posted by r carl

By removing the system. There are diesel guys in the diesel forums that know way more than me, they eat, sleep, and live diesels. You can go to one of the popular diesel forums and learn there what needs to be done. Personally if I had a 2008 I would remove the DPF and put on a free flowing cat back exhaust.

Thanks, Rivet Master carl! I'll keep looking. The few dmax diesel forums i've been able to find all talk way over this newbies head. I long for a pro who would be willing to share the way this AS community does. I'm not a mechanic, so would need to hire the work done somewhere here in Central Virginia.

JFScheck · 07-08-2011, 03:48 PM

Quote:

Originally Posted by moosetags

Thanx for the info, John. After the Titan retrofit, you will be hovering at near 1,000 mile range. Please keep us posted on the tank install and results. mAre you doing the tank installation yourself or having it done?

Brian

Brian, got some pictures of the installed tank over here if your interested...

D Air Cloud · 07-09-2011, 02:40 PM

Quote:

Originally Posted by DKAir

We've also had the fuel filter changed with the oil changes. The wisdom of the internet says this is cheap insurance for expensive injectors, but I am not sure it is necessary as the DIC still shows lots of life. What are people's thoughts on this?

-DK

I agree, protecting the fuel system is important. My fuel filter gets changed about every ten thousand miles, which has been before the DIC indicates it needs to be changed. To help the fuel filter, I try to only fill up at stations that pump a lot of diesel, such as truck stops. I also keep a new fuel filter in the truck, just in case I get a load of bad fuel.