I am looking at getting a newer truck sometime soon. I really want a full size chevy. I have driven a friends 1500HD with the 6.0 and I loved the way that truck drove. The power was available anywhere in the RPM range. Engine felt very strong and the trans seemed to work well together with that engine. I will be using the truck as my DD and a play truck, I will take it into some mild off roading situations nothing that extreme. I have not driven the 8.1 but I like the idea of a chevy big block and the Ali trans but I have not driven one. So what do you all reccomend? I only ask about the 8.1 because the gas mileage does not appear to be that much different from the 6.0. I am also considering the 5.3 but I really want a vehicle with a lot of power. I have had 4 cyl vehicles my whole life and plan on moving to an area with plenty of mountains and will need more power than my current truck. Thanks in advance. I really want to know what the driving experience is like with the 8.1.

I really want to know what the driving experience is like with the 8.1.

Reach for your wallet whenever you pass a gas station. :D ;) :D

Unless you have a real need for the extra payload/trailering capacity I'd stick with the 1500 series. Since it sounds like you will be running empty most of the time you will get better milage out of the 6.0 vs the 8.1 - probably at least 2 MPG, maybe more. Also, don't discount the 5.3 without driving one. Without all the extra weight of the 2500 or 3500, the 1500 with the 5.3 can really haul down the road and get great gas milage.

I need the 2500 series truck for my work. I also need the 8.1. (actually I need D-Max but that's another story). But, if I didn't need the HD truck I'd much rather drive one like my brother's 1500 CC with the 5.3.

From what I've found, average unloaded MPG's are:

8.1 = 12*
6.0 = 14*
5.3 = 18*

* Your milage may vary. Don't drink and drive. Know when to stop before you start.

Thanks Jay, I appreciate the info. How do you like your 8.1? Does the power come on fast like the 6.0 or is it a much slower rever like a diesel? thanks again.

8.1 comes on pretty quick, definitely blows by a 6.0 when loaded. If you want decent MPG stay away from the 8.1, I've gotten a best of 13.9, last check I did was 12.2. Now my truck runs around 7100 lbs+ due to weight of lift, tires, deep tool box full of crap and GN hitch so it pulls a few tons around even "unloaded".
My sis-in-law has a burb with the 5.3 and it hauls the mail fine, think you may want to try one of those first.
IMO I've found most of the folks with 6.0 HD's are those who need the extra capacity at times, like pulling TT, a lot with dmax just want a diesel, those of us with the 8.1 use it and don't want the extra maintainance $$$ associated with the diesel. VERY FEW get the 8.1 just to have a big block, they're thirsty.
There's times I wished I'd kept my 98 with the 350.... the 8.1 just isn't a good commuter vehicle, the wifey's S10 crew is but she uses it everyday in the real estate business.

No flame wars please.... just my $.02

BTW if you want a big block, better get it now.... not available in the 08's (at least from what I've seen so far)

The power comes on pretty quick and steady on the 8.1. I wouldn't call it a screamer - it's more of a steady buildup of seemingly endless power. I'm not into mods and such, but I get the feeling that the stock 8.1 operates at way below it's potential. Make no mistake - even in stock form it's an awsome engine. One of my guilty pleasures is to watch people change lanes to get next to me at a stoplight - while I'm pulling a trailer - then blow them away when the light turns. Great fun but you can watch the fuel guage go down as the revs go up.

Overall I'm very happy with the engine. I had 5.7's in my two previous 2500's and there is much more power. Up until this truck, I had always had a straight shift but the Allison transmission has got me sold on automatics from here on out. The 8.1 does burn some oil, usually a quart between changes.

I still say to consider your usage. If you need the bigger, heavier truck then go ahead and get one. If you want the bigger engine just to have it then be very aware that it is an expensive choice. I've done many trips in convoy with my brothers 5.3 - sometimes empty and sometimes both pulling trailers. He usually gets anywhere from 1-1/2 to 1-3/4 times the fuel milage that I get.

I have had both. I had an 01 2wd 4:10 with a 6.0. Average about 10 mpg in town. I now have an 03 2wd 4:10 Ali with the 8.1. There is no comparison to the extra power. I average around 10 in town for it as well. For my money the 8.1 anytime.

Thank you all very much for the info and opinions. Please keep em coming. If I come across a nice used 8.1 I would love to get it. I might one day be towing a 5th wheeler and could really use the power of the 8.1 but that is at this point a remote chance. Thanks again everyone