i'm new on this site and i need advise on motors. i'm looking to buy a 05 silverado or gmc 4x4 extcab sb z-71. 4.8l or 5.3 aluminum block are my 2 options.i have no interest in the 5.3 flex fuel. truck will be used daily (50 miles) and used once in awhile to haul fire wood,dirt etc.

i need advise on what motor i should get and axle ratio (3.73 or 3:42).

how reliable are the aluminum blocks and can i get alot of miles on one (150,000 or more)? i know they have been around for awhile but i'm cautious about having a steel cyl sleeve with aluminum.i've always had iron blocks.

i have a 2001 2500 dodge gas pig now which i have to dump. gas is an issue at $1.95 per gal. i'm open for opinions. thanks

 

Just get the 5.3L, the gas milage difference wil lbe negligible due to the extra weight of your truck.

On average you'll get between 15-17mpg depending on milage, mine slowly got worse but then again it may have just been the added mods.

Why not get a used truck? The motors hold up really well in these trucks so buying new is kind of a waste IMO unless you are getting a smokin deal on one.