Here in Australia we work with kilometers not miles and oil changes are recommended at 10,000K intervals or 6 months which is a bit over 5,000 miles for normal driving conditions. Would recommend you stick to 5000 mile oil changes as information I have read suggests your American 3LTR V6 engines have been having problems with sludge. I, myself change my oil every 6 months and as I only cover a low amount of Ks in that time my oil changes occur at less than 5,000K intervals. What the hell its still cheap insurance! :)
