Going Diesel

[dcsnyder]

I have a 04' 2500HD, 6.0L. I just started pulling a camper with it. I wound up with a little more camper than I had planned on getting. It's abont 8500 lbs. With the truck loaded I estimate the CGVW is very close to 16000lbs. I'm considering moving up to a bigger engine. The truck really doesn't do bad pulling until I hit a long uphill grade. 3500-4000rpm really seems like it's screaming. I figure I could throw a few hundred bucks at the 6.0L to get some additional torque or just get a larger engine.

The 8.1L would be a big improvement but I'm concerned about the gas milage. I believe diesel engines generally do a little better than gas engines. I've been told recently by someone that the new diesels make great power but drop fuel milage, similar to a gas engine, when towing.

Questions:

1. What kind of improvements could I expect to get out of the 6.0L with an new intake, exaust and a Hypertec programmer?(I already have the programmer from another truck. Hyertec will reprogram it for my current truck. I'm Not intersted in buying another type of programmer)

 

2.Anyone have any experience with the 8.1L? fuel milage empty vs. towing

 

3.What does anyone know about the new Duramax diesel? 360HP, 650Flbs torque sounds great but man are they expensive. I'm not sure all that power isn't a little overkill, especially considering the cost of diesel fuel. I'm thinking I'd have to see a sizable difference in fuel milage, compaired to the 8.1L, to sway me to the diesel.

Looking for some advise!!

 

dcsnyder

[Trouttrooper]

I can't give any personal experiance w/ the Dmax but I've talked to a few Dmax owners that are dissapointed that the mileage isn't what they thought it would be. I've heard 12-15 when towing.

 

I went from a '99 2500 w/ 6.0 and 4.10 gears to a '05 3500 w/8.1 and 4.10 gears.

 

The 6.0 empty averaged 14 mpg. When towing (horses, hay, wood) a minimum of 8,000 lbs trailer weight) it dropped to about 8 mpg.

 

The 8.1 so far empty average is 12.5 mpg and towing average comes out to 10.8 mpg (I keep a log book on gas fill up).

 

The 8.1 smokes the 6.0 for towing power (duh ) and since my truck is towing more than empty, my yearly mpg average is actually better w/ the 8.1. I have yet to feel the need for more power with the 8.1.

 

I'm not a lead foot, especially when towing. I have no need to be the first across an intersection, although I'm not some granny driver either. I believe this is the biggest factor for why some get worse mileage.

 

[zippy]

the 6.0L even with some mods isn't going to pull how you want it to. you don't buy a 364 cubic inch engine to pull heavy loads.

 

the 8.1L will pull about anything you hook it to with ease and with about the same milage as your 6.0L with a trailer behind it. empty the 6.0L will get better milage though.

 

the diesel is the way to go for pulling. the milage is outstanding which means for less stops and less cost for taking long hauls. the pulling power is outstanding simply because of the boost. if they turbo'd the gas engines they'd have as much or more torque as the diesel, but crap for milage. the initial cost though is pricey. if you plan to pull alot, my recomendation would be to either put a 6.7L in place of the 6.0L (direct bolt in other than programming) or get yourself a diesel. the other good thing about a diesel is that they don't mind being run hard as you can possibly run it and not speed too much. the 6.7L with the right cam and programming would pull as well as the 8.1L with milage about the same as the 6.0L.

[vhato]

I agree with the others. Dumping money into the miracle mods for the Vortec 6000 (Intake, Tune, Headers, Cat-Back) isn't gonna turn it into the torque monster the Vortec 8100 is for what $800? Not even a Whipple or Radix Charger can bring you into LBZ Duramax levels of torque and the overall cost would be the same AND you would have to run the more expensive Premuim Fuel, not to mention toasting the 4L80-E at some point.

 

So why buy the more? Down here in the south, unless you go into Hydrocarbon situations there isn't really a reason to choose the Duramax over the Vortec 8100. The towing capacity's are basically the same and the what I see people tow they could easily get by with much less truck.

 

Up north however, that TurboCharger solves all problems. The difference in air pressure isn't even an issue and long uphill pulls are so easy grandma could do it.

 

If I could buy again I would DEFINATELY get the Vortec 8100/Allison 1000 combo. The increase in cost is minimal and the overall cost of ownership is close to that of the Vortec 6000/4L80-E combo. But I live down in the flat lands.

 

1. HyperPing: Not gonna give you the power where you expect it. You need pulling power, not 1/4 mile performance. But, hell, you have it now, install it. Adding the Intake and Exhaust will change the performance characteristics of the engine. Part Throttle power will be greatly improved, but WOT will suffer on those uphill pulls in 3rd or 2nd gear when you need a little ummmph. You will definately feel like the truck has more power at 90% throttle than 100% with these mods and a stock tune or HyperTech Tune. You will probably loose WOT power, only a custom tune will solve it or some custom upgrades with a Diablo Predator Programmer. I know you didn't wanna here it. There is a good explanation why this is true, but I won't get into it.

 

2. I know 2 guys with Vortec 8100's and no personal experience as to how much better they are for towing and/or mileage. My only real source of knowledge in this are threads like these.

 

3. The new Diesel isn't just a programming upgrade (although it is there).

a. The Fuel rail pressure has been increased from 23,000 psi to nearly 27,000 psi.

b. New seven-hole fuel injectors that spray 5 times per cycle

c. New 32-Bit Engine Management Computer

d. New Engine Block with more material for main bearing support

e. New Main Bearings

f. Thicker Connecting Rods

g. Larger piston pins

h. Relocated Glow-Plugs into the path of the Injectors for better cold start

i. 1,000 Watt air Heater for better cold start

j. Driver Selectable through the DIC for an Elevated Idle Mod

k. Lowered Compression ratio (from 17.5:1 to 16.8:1) for lower noise output

 

The new Allison 1000 is also greatly improved

 

a. Double OverDrive for improved fuel savings

b. increase the torque converter to 310mm.

c. Improved Solenoids

d. new computer

e. increase in the number of clutches for more torque transfer

f. 22-spline Pump

g. New planetary gears to make it quieter

h. Tap Shifter for manual shifting of the Automatic

i. Grade-Braking when using Cruise Control for safety

j. Traction Control user seleactable option for safety at the drivers request