Engine oil Mobil or OEM Mazda

As a Mercedes-Benz guy, I've used Mobil One European Formula 0w40 in them for decades. It is very good oil. I have well over a million miles on Mercedes-Benz cars using that oil with the extended (10K-15K mile) change interval with zero issues. Several of my cars have gone over 200,000 miles.

But if you want the short of it:

ANY high mileage full synthetic 5w-30 oil will do great. Mobil 1? Sure. Amazon Basics? Hell yeah. Wal-Mart's Supertech? Send it.

I dropped some 0W-30 Mobil 1 this winter, and my sol with a d15b7 loved it. Made cold starts very smooth, and noticed no reasons not to continue running it.

I've used only 5w30 full synthetic (usually Mobil 1, sometimes others) since I bought mine 15 years ago (D15B7). Using the high-mileage variety nowadays, supposed to help out the old seals etc. Just over 150k miles but engine runs very smooth so seems to be doing the trick.

I use Mobil 1 synthetic blend HIGH MILAGE 5w-30. I think the high milage formula is the best for these old engines.

My G37x likes mobil 0w 30 car feels great with this oil

Been using Mobil1 5W-30 since 1998... GTI now has 232,500 miles and is smooth as silk. I do oil changes on the dot at 5K miles.

The part number they listed for each quart of oil was G-E55-540-1B-DSP . Look that up and you'll see why oil changes are expensive. Somehow I don't think the oil is better than the Mobil1 I buy at Walmart at $24 for 5 quarts.....

Mobil1 should be fine. People are anal about oil but I've got 90k on my wrx with regular oil changes every 3-4k miles with Pennzoil ultra platinum or Mobil1 Extended Performance.

I was using Mobil 1 fully synth 5w40 on my old cab with no problem at all. good pressure at idle and at 2k. I used this oil in my new cab (same engine) and boom! No oil pressure at for the first 15 secs. Then it immediately jumped to 5 bars and finally settled down to 1 bat maybe less. However, I saw a dramatic increase in oil pressure even with the 5W40 mobil 1 when I switched to a 2L oil pump. Idle pressure was arround 2bars. Although I used it last summer and it worked just fine throught my vacations in Greece.