I just registered and this is my first thread.

contingent upon signing of contracts my company may be purchasing 3 new trucks.
2005 3500GMC dump rackbody duramax(diesel)
2 -2005 ext. cab GMC Pickups undecided weather 2500hd or 3500(gassers).

My question is about what size engine. The 6 liter or the 8. Same HP, and GMC site said same torque? I thought the reason for the 8 would be about torque. The 8 will eat more gas. I am thinking the 6 will be fine for my needs.

Please correct me if I am wrong. I,m sure there is some reason for the 8.

More info.- They will be 6 foot beds, they will have plows in the winter and a possibility of spreader. At some point they may tow 20' to 24' enclosed trailer.

To sum it up Why should I by the 8. Why should I not?

8.1 = 450ftlbs

6.0 = 360ftbls

same mpg

pulled off the GMC web site:

Engine, Vortec 6000 V8 SFI, (300 HP [223.8 kW] @ 4400 rpm, 360 lb.-ft. [486.6 N-m] @ 4000 rpm) (LQ4)

Engine, Vortec 8100 V8 SFI, (330 HP [245.8 kW] @ 4200 rpm, 450 lb.-ft. [607.5 N-m] @ 3200 rpm) (L18)

Just be sure to get the 4.10 gears with 8.1 also.

Without a doubt, go with the 8.1. You won't be disappointed. I've owned both engines and the 8.1 is by far the way to go. Same mileage but the 8.1 just flat out hauls with or without a load. It's fantastic engine plus you can get the Allison with the 8.1...another big bonus that you shouldn't pass up.

you replies were helpful, thank you.

Buy The Duramax! You will get between 12-18mpg. And you will never run out of power! Change the oil And Fuel filter and your good for 250,000 +.

The HD's have a 6.5' and 8' bed option.

From a business owners' standpoint : If the two gassers put a lot of miles on, then the 1-2 mpg difference will save you a lot of money in the long run if your the one paying the gas bill. If not a lot of miles, then go 8.1

DEWFPO