There will be strong support in this forum for all three, and then some. I'll add Mobil1 Turbo Diesel. Big bad ExxonMobil gets a bad rap, maybe deservedly so, but their R&D is second to none, also top quality base stocks and additives. Mobil 1 is their signature lube, but it's a low volume product and they don't really make much money on it. It's more of a marketing tool. The last time I checked it's only available 5w40. The 5W gives you easy cold starts. Best part, you can buy it at Wal Mart. I've been running Mobil1 about 30 years now (change at 10k) in gassers, and now in my diesel. I sold every one of my gassers at 200-250k miles, not an engine breakdown among them. Not a spec of sludge in any of them either. Decision on synthetics should, of course, be based on annual mileage. The time the oil is in the engine is the important factor. I'll soon be reducing my annual mileage from 25,000 to about 10,000, mostly short towing/hauling trips. I will then switch back to 15w40 dino oil as I don't like going more than 6 months w/o an oil change. No need to waste $$$ on syn at 5k interval.