I try not to wait for the engine life monitor. Usually around 5000 miles for the engine using Mobil 1 synthetic and Mobil filter. Suspension also greased at the same time with synthetic grease.
Transmissions and differentials are at 20-25000 miles using synthetics.
The blazer gets regular dino oil at 3000 mile intervals with the mobil filter.
2013 Silverado: 28,000 miles
2006 Silverado:175,000 miles
2003 Tahoe: 178,000 miles
2002 Silverado: 162,000 miles
2001 Yukon: 206,000 miles
2000 Sierria: 250,000 miles
2000 Blazer: 138,000 miles
1999 Silverado: 258,000 miles
All done in house..
There is a fair amount of petroleum products consumed around here!
Andy