I have a few questions

[Larry Young]

I have a 2002 GMC Sierra 5.3 bought with 98,000 original miles 1 owner does the 5.3 burn oil in most of this model and where does your voltage gauge normally run any info will be greatly appreciated 

[chem_man]

I can't answer the oil question other than saying my 99 with 30k on it does not burn any.  Regarding the voltmeter on the dash, the needle normally sits just above the 14 VDC mark while the engine is running.

[davester]

I don't know about your engine, but your alternator is likely computer controlled, so the voltage will vary with demand, and not like earlier vehicles that have more constant voltage.

[sefiroxx]

My 01 burned about 1/2at per oill change - a gm engineering spec allowance.

14v on 01 5.3 burb and 04 4.8 Sierra