Formula Shell GF-3 for '00 Sierra 5.3L

Calgary AB
Well, well.... I've had alot of fun perusing this forum - alsorts of tidbits here!! First I'll introduce myself: I run an industrial gas turbine testcell for a living, speaking of living that's in Calgary AB Canada. Here's the question. I've been using Formula Shell 5W30 GF-3 for a few years, mainly because it's less than $2CDN/L. The sole application for this product has been in older american iron (80's). I now own a '00 Z71 Sierra and would just like some kind input into this application. The formula shell thing has never made sense to me as they only market one retail mineral based motor oil, while other oil companies seem to have a mineral brand for each day of the week. Why is it so cheap? '00 Sierra (TBA) '00 Honda CBR929RR (Motul 5100 10W40) [ March 11, 2003, 12:49 AM: Message edited by: sub_zero ]